CN118817610A - Wafer inspection method based on wafer inspection system and related products - Google Patents

Abstract

The present application discloses a wafer detection method based on a wafer detection system and related products thereof, belonging to the field of wafer detection. The wafer detection system includes a detection computer, a motion computer, and a camera, and the method includes: in response to the interactive information of the detection computer, switching the target objective lens and determining the target detection position based on the motion computer; in response to the control signal of the motion computer, controlling the camera to collect the image to be detected based on the target objective lens and the prism of the wafer to be detected at the target detection position; transmitting the image to be detected to the detection computer, and determining the detection result of the wafer to be detected based on the detection computer. Based on the above wafer detection method based on the wafer detection system, the detection cost of wafer defects can be reduced.

Description

Wafer inspection method based on wafer inspection system and related products

Technical Field

The present application generally relates to the field of wafer inspection, and more specifically, to a wafer inspection method, system, device and computer-readable storage medium based on a wafer inspection system.

Background Art

As a basic material for semiconductor devices, wafers are prone to various surface or internal defects during the manufacturing process, which can seriously affect the performance and yield of integrated circuits. In order to ensure that the produced wafers meet quality requirements, manufacturers usually use three-sided inspection and other methods to perform defect inspection on the front, back and sides of the wafer.

In previous inspection methods, it is difficult to complete multiple inspection requirements for wafer defects in one device at the same time. During the equipment switching process, manual assistance is usually required. However, manual operation has a high risk of fragmentation and sometimes causes secondary damage to the wafer related to electrostatic discharge, thereby affecting the inspection cost of the wafer. In view of this, it is urgent to provide a wafer inspection solution to reduce the inspection cost of wafer defects.

Summary of the invention

In order to at least solve one or more of the technical problems mentioned above, the present application proposes a wafer inspection method, system, device and computer-readable storage medium based on a wafer inspection system in multiple aspects. Through the technical solution of the present application, the detection cost of wafer defects can be reduced.

In a first aspect, the present application provides a wafer inspection method based on a wafer inspection system, wherein the wafer inspection system includes an inspection computer, a motion computer, and a camera, and includes: in response to interactive information of the inspection computer, switching a target objective lens and determining a target inspection position based on the motion computer; in response to a control signal of the motion computer, controlling the camera to capture an image to be inspected at the target inspection position based on the target objective lens and a prism of the wafer to be inspected, wherein the image to be inspected includes a front image, a back image, and a side image of the wafer to be inspected; transmitting the image to be inspected to the inspection computer, and determining an inspection result of the wafer to be inspected based on the inspection computer.

In some embodiments, the switching of the target objective lens in response to the interactive information of the detection computer and determining the target detection position based on the motion computer include: based on the detection computer, selecting and switching the target objective lens according to the detection requirements in the interactive information; and parsing the interactive information based on the motion computer to determine the target detection position.

In some embodiments, in response to the control signal of the motion computer, controlling the camera to collect the image to be detected based on the target objective lens and the prism of the wafer to be detected at the target detection position includes: in response to the control signal of the motion computer, controlling the platform carrying the wafer to be detected to move to the target detection position; in response to the control signal of the motion computer, adjusting the light source of the light source controller and controlling the rotation axis of the platform to rotate; in response to the shooting trigger signal of the light source controller, controlling the camera to collect the image to be detected from the prism of the wafer to be detected based on the target objective lens.

In some embodiments, transmitting the image to be inspected to the inspection computer and determining the inspection result of the wafer to be inspected based on the inspection computer includes: based on the inspection computer, allocating the image to be inspected to an algorithm computer; based on the algorithm computer, performing defect detection on the image to be inspected and outputting initial inspection results; based on the inspection computer, summarizing the initial inspection results to obtain the inspection results.

In some embodiments, the control signal of the motion computer controls the camera at the target detection position before capturing the image to be detected based on the target objective lens and the prism of the wafer to be detected, and also includes: generating a photographing point trajectory based on the detection computer according to the size information of the wafer to be detected; and outputting the control signal based on the motion computer according to the photographing point trajectory.

In some embodiments, after transmitting the image to be inspected to the inspection computer and determining the inspection result of the wafer to be inspected based on the inspection computer, it also includes: responding to an automatic re-judgment instruction, determining defect position information based on the inspection result based on the inspection computer; using the defect position information as interactive information, executing the step of responding to the interactive information of the inspection computer, switching the target objective lens and determining the target inspection position based on the motion computer.

In some embodiments, the method also includes: in response to a pulse signal generated when a platform carrying the wafer to be inspected moves, sampling data on the wafer to be inspected based on a sensor; receiving data information returned by the sensor based on a detection computer; and determining measurement data of the wafer to be inspected based on the data information.

In a second aspect, the present application provides a wafer inspection device based on a wafer inspection system, wherein the wafer inspection device based on a wafer inspection system comprises: a processor; and a memory storing program instructions for wafer inspection based on the wafer inspection system, wherein when the program instructions are executed by the processor, the above-mentioned method steps are implemented.

In a third aspect, the present application provides a computer-readable storage medium storing computer program instructions for wafer detection based on a wafer detection system. When the computer program instructions are executed by a processor, the above method steps are implemented.

In a fourth aspect, the present application provides a wafer inspection system, which includes: an inspection computer, used to exchange information with a motion computer and an algorithm computer to determine the inspection results; a motion computer, used to exchange information with the inspection computer, control a camera, a light source controller and a platform mechanism; an algorithm computer, used to inspect the image to be inspected and return the initial inspection result to the inspection computer; a camera, used to collect the image to be inspected; and a light source controller, used to adjust the light source to assist the camera in taking images.

Through the wafer detection method, system, device and computer-readable storage medium based on the wafer detection system provided above, the embodiment of the present application responds to the interactive information sent by the detection computer, controls the switching of the target objective lens and determines the target detection position based on the motion computer. Subsequently, in response to the control signal of the motion computer, the camera is controlled to detect the prism image of the target objective lens and the wafer to be detected at the target detection position, and finally, the image to be detected is transmitted to the detection computer, and the detection computer determines the detection result of the wafer to be detected. Through the defect detection method of the wafer performed by the defect detection device based on the above wafer, the detection cost of wafer defects can be reduced. Further, in some embodiments, by responding to the automatic re-judgment instruction, the defect position information corresponding to the instruction can be determined based on the previously determined detection result, so that it is used as interactive information to perform the wafer detection step based on the wafer detection system again, so as to realize the automatic re-judgment function for wafer defects. Further, in some embodiments, the detection computer can also receive the data information returned by the measurement sensor, and determine the measurement data of the wafer to be detected according to the data information, that is, the wafer detection device based on the wafer detection system in the present application also has a measurement function.

BRIEF DESCRIPTION OF THE DRAWINGS

By reading the detailed description below with reference to the accompanying drawings, the above and other purposes, features and advantages of the exemplary embodiments of the present application will become easy to understand. In the accompanying drawings, several embodiments of the present application are shown in an exemplary and non-limiting manner, and the same or corresponding reference numerals represent the same or corresponding parts, wherein:

FIG1 is a flow chart showing a wafer inspection method based on a wafer inspection system according to an embodiment of the present application;

2 is a flow chart showing a wafer inspection method based on a wafer inspection system according to another embodiment of the present application;

FIG3 is a flow chart showing controlling a camera to capture an image according to an embodiment of the present application;

FIG4 is a flow chart showing determination of wafer defect detection results according to an embodiment of the present application;

5 is a flow chart showing a wafer inspection method based on a wafer inspection system according to yet another embodiment of the present application;

6 is a flow chart showing another wafer inspection method based on a wafer inspection system according to an embodiment of the present application;

FIG7 is a diagram showing the architecture of a detection system according to an embodiment of the present application;

FIG8 is a diagram showing a comparison of computer detection images using an algorithm according to an embodiment of the present application;

FIG9 is a schematic diagram showing the wafer 3D measurement effect of an embodiment of the present application;

FIG10 is a complete control flow chart showing a wafer detection method based on a wafer detection system according to an embodiment of the present application;

11 is a system schematic diagram showing a wafer inspection device based on a wafer inspection system according to an embodiment of the present application;

FIG. 12 is a schematic diagram showing a prism arrangement according to an embodiment of the present application.

DETAILED DESCRIPTION

The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

It should be understood that the terms "include" and "comprising" used in the specification and claims of the present application indicate the presence of described features, wholes, steps, operations, elements and/or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and/or collections thereof.

It should also be understood that the terms used in this application specification are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in this application specification and claims, unless the context clearly indicates otherwise, the singular forms of "a", "an" and "the" are intended to include plural forms. It should also be further understood that the term "and/or" used in this application specification and claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes these combinations.

As used in this specification and claims, the term "if" can be interpreted as "when" or "upon" or "in response to determining" or "in response to detecting," depending on the context. Similarly, the phrases "if it is determined" or "if [described condition or event] is detected" can be interpreted as meaning "upon determination" or "in response to determining" or "upon detection of [described condition or event]" or "in response to detecting [described condition or event]," depending on the context.

The specific implementation of the present application is described in detail below with reference to the accompanying drawings.

Referring to Figure 1, Figure 1 is a flow chart showing a wafer detection method based on a wafer detection system according to an embodiment of the present application. As shown in Figure 1, the wafer detection method based on the wafer detection system includes: at step S101, in response to the interactive information of the detection computer, switching the target objective lens and determining the target detection position based on the motion computer. In this embodiment, the wafer detection step based on the wafer detection system is performed by a wafer detection device based on the wafer detection system (hereinafter referred to as the detection device), the detection device is compatible with the wafer three-sided detection station, and the components in the detection device constitute a wafer detection system (hereinafter referred to as the detection system). To facilitate understanding of the composition of the wafer detection system and the functions of each component, the following is explained in conjunction with Figure 7. Figure 7 is a diagram of the detection system architecture. The detection system framework includes a detection computer, a motion computer, an algorithm computer, a camera (including a detection camera and a Review camera), a light source controller, and a gigabit switch. The detection computer, motion computer and algorithm computer can be understood as the logical operation units responsible for different functions in the detection equipment. The detection computer can exchange position information and signals with the motion computer. In addition, it is responsible for obtaining the images to be detected collected by the camera, assigning them to the algorithm computer for defect detection processing and finally determining the detection results. The motion computer can exchange information and signals with the detection computer. It is mainly responsible for controlling the platform mechanism and the light source controller, and is also responsible for triggering the photo signal so that the camera can collect images. The algorithm computer is responsible for defect detection processing of the images to be detected distributed by the detection computer. The number of algorithm computers can be multiple. The detection camera and the review camera are both used for image acquisition tasks. The detection camera is mainly responsible for the acquisition of wafer images in the initial inspection, while the review camera is responsible for acquiring the review images of defective wafers that have been detected. The light source controller and the optical machine are responsible for light source regulation, thereby assisting the camera to collect clearer images. The gigabit switch is responsible for data transmission in the entire system architecture.

In one embodiment, when the wafer to be inspected is loaded on the platform and arrives at the three-sided inspection station, the inspection computer sends interactive information to the motion computer, including the inspection position information corresponding to this inspection. In addition, the inspection computer also needs to select and switch the target objective lens according to the inspection requirements of this time. As an optical component, the objective lens can assist the camera in capturing clear images of the wafer at a certain magnification. The camera can be equipped with multiple objective lenses to adapt to different inspection requirements. When the inspection computer selects the objective lens, the inspection computer can judge and respond according to the instructions or signals triggered by this inspection. Then, after receiving the interactive information sent by the inspection computer, the motion computer parses it and determines the target inspection position.

Further, at step S102, the motion computer sends a control signal to control the camera to collect the image to be detected at the target detection position based on the previously switched target objective lens and the prism of the wafer to be detected. In one embodiment, the motion computer outputs a control signal that can control the movement of the platform mechanism so that the camera can collect images of the wafers to be detected carried by it one by one. The control signal includes a photo trigger signal, which is used to control the camera to perform a picture-taking operation on the wafer to be detected at the target detection position to obtain the image to be detected. It should be noted that a prism module is provided at the target detection position, and the prism module corresponding to the wafer to be detected at the target detection position includes a plurality of prisms, which can change the propagation direction of light. These prisms are placed according to specific positions and can refract the front, back and side images of the wafer to be detected, so that the camera can collect wafer images of corresponding viewing angles based on the target objective lens.

In a feasible implementation, the camera can use a large-target camera, which has a large photosensitive surface, which is convenient for taking high-quality and high-resolution images of the wafer to be inspected. Referring to Figure 12, Figure 12 is a schematic diagram of the prism setting. The prism module shown in the figure includes seven prisms, and the first prism is a total reflection prism, which is used to refract the edge image (i.e., the side image) of the wafer to be inspected to the large-target camera. The second prism to the seventh prism are all equipped with two right-angle surfaces and a bevel reflection surface. The second prism and the third prism are respectively arranged above and below the wafer to be inspected, and the second prism and the fourth prism bevel reflection surfaces are perpendicular to each other and arranged oppositely. In addition, a first flat glass is arranged between the second prism and the fourth prism to extend the optical path from the second prism to the fourth prism. The bevel reflection surfaces of the fourth prism and the sixth prism are parallel to each other and arranged oppositely. The bevel reflection surface of the sixth prism faces the first prism. Similarly, the bevel reflection surfaces of the third prism and the fifth prism are perpendicular to each other and arranged oppositely. In addition, a second flat glass is provided between the third prism and the fifth prism to extend the optical path from the third prism to the fifth prism. The oblique reflection surfaces of the fifth prism and the seventh prism are parallel to each other and arranged opposite to each other. The oblique reflection surface of the seventh prism is also facing the first prism. The dotted arrows in Figure 12 indicate the refraction path of the light, and the front image of the wafer to be inspected is refracted to the first prism via the second prism, the first flat glass, the fourth prism and the sixth prism. The back image of the wafer to be inspected is refracted to the first prism via the third prism, the second flat glass, the fifth prism and the seventh prism, and the first prism can directly refract the side image. Finally, the first prism can return the front, back and side images of the wafer to be inspected to the camera located above it, thereby achieving the three-sided inspection effect of the wafer using a single camera.

When the shooting signal is triggered, the camera is in the triggered state, and the prism is magnified through the eyepiece to collect the images to be tested from the front, back and side perspectives. Since multiple prisms are set at the target detection position, the detection equipment does not need to add shooting modules for other perspectives. Only one shooting module can collect images of the front, back and side of the wafer from the prism corresponding to the wafer. It can be understood that the camera running in the initial inspection project is the inspection camera, and the camera running in the defect review project is the Review camera.

After executing the above steps S101 and S102, the process can proceed to step S103. In step S103, the image to be inspected captured by the camera will be transmitted to the inspection computer, which will perform calculations on it to determine the inspection result of the wafer to be inspected. In one embodiment, the inspection computer assigns the image to be inspected to the algorithm computer, and the algorithm computer uses a specific defect recognition algorithm to inspect the image to be inspected and output an initial inspection result, which is then transmitted back to the inspection computer, which summarizes the output content of its algorithm computer to obtain the final inspection result.

In this embodiment, the detection equipment greatly improves the detection efficiency and reduces the detection cost through the above steps, and also reduces the secondary damage caused by electrostatic discharge caused by traditional manual operations. In addition, it also makes the detection results more objective and accurate, providing a reliable basis for wafer process optimization and quality control management.

FIG2 is a flow chart showing a wafer inspection method based on a wafer inspection system according to another embodiment of the present application. It can be seen from the following description that the wafer inspection method based on a wafer inspection system shown in FIG2 can be a specific manifestation of the method described in the foregoing text in combination with FIG1 , so the foregoing description can also be applied to the following description of each step of FIG2 .

As shown in FIG2 , the wafer detection method based on the wafer detection system may include: at step S210, in response to the interactive information of the detection computer, switching the target objective lens and determining the target detection position based on the motion computer. In one embodiment, step S210 may include: at step S211, based on the detection computer, selecting and switching the target objective lens according to the detection requirements in the interactive information. In one embodiment, the front, back and side image acquisition of the wafer can be performed by different objective lenses to meet the acquisition requirements of the corresponding viewing angles. For example, low to medium magnification objective lenses are used for front detection, and high magnification objective lenses are used for side detection. When the detection computer switches the objective lens according to the detection requirements in the interactive information, it can select the target objective lens based on the correspondence between the detection requirements and the objective lens established in advance and switch it through a control system (such as an electric actuator or a stepper motor, etc.), thereby ensuring that the switching action of the objective lens is accurate and stable.

At step S212, the motion computer can parse the interactive information transmitted by the detection computer to determine the target detection position. In one embodiment, the detection computer can send the interactive information to the motion computer through a network, serial port or other communication method, and the motion computer receives and parses the detection position information, which can be expressed in the form of coordinates. In the subsequent process, the motion computer plans a path trajectory based on the target detection position corresponding to the detection position information and outputs a control signal based on this to control the movement of the platform mechanism. It can be understood that if this detection is a defect re-judgment task, the motion computer parses it out as the defect photo position, that is, the position of the uncertain defect on the wafer that has been detected before.

As further shown in FIG. 2 , at step S220 , the motion computer sends a control signal to control the camera to collect the image to be detected at the target detection position based on the previously switched target objective lens and the prism of the wafer to be detected. Then, at step S230 , the image to be detected collected by the camera is transmitted to the detection computer, which performs calculations on it to determine the detection result of the wafer to be detected. Steps S220 and S230 may be the same or similar to steps S102 and S103 described in conjunction with FIG. 1 above, and will not be repeated here.

Fig. 3 is a flow chart showing the control of the camera to collect images in an embodiment of the present application. It can be seen from the following description that the wafer inspection method based on the wafer inspection system shown in Fig. 3 can be a specific manifestation of the method described in the foregoing text in combination with Fig. 1, so the foregoing description can also be applied to the following description of each step of Fig. 3.

As shown in FIG3 , the wafer detection method based on the wafer detection system may include: at step S310, in response to the interactive information of the detection computer, switching the target objective lens and determining the target detection position based on the motion computer. Then, at step S320, the motion computer sends a control signal to control the camera to collect the image to be detected based on the previously switched target objective lens and the prism of the wafer to be detected at the target detection position. In one embodiment, step S320 may include: at step S321, in response to the control signal of the motion computer, controlling the platform carrying the wafer to be detected to move to the target detection position. It is understandable that the control signal sent by the motion computer includes a signal for controlling the movement of the platform mechanism, a signal for controlling the light source controller, and a photo trigger signal. The motion computer plans a path trajectory based on the parsed detection position information and outputs a control signal based on this. In a feasible implementation, the motion computer can send the control signal to the actuator (such as a motor, a servo system, etc.) of the platform mechanism through a cable or wirelessly, and the actuator executes the control signal to control the platform mechanism to move to the target detection position.

Optionally, in another feasible embodiment, in order to ensure smooth and precise movement of the platform mechanism, a sensor for detecting the current position and state of the platform can be provided on the platform mechanism, which can feed back the current position and state to the motion computer. If a deviation is detected, the motion computer will adjust the control signal according to the feedback data to adjust the position and motion state of the platform mechanism, thereby ensuring smooth movement of the mechanism.

Then, at step S322, in response to the control signal of the motion computer, the light source of the light source controller is adjusted and the rotation axis of the platform is controlled to rotate. Among them, the light source controller can adjust the brightness and intensity of the light source to ensure that the lighting conditions during image acquisition are suitable for different detection requirements. When the motion computer outputs the control signal to the light source controller, it can adjust different lighting modes (such as backlight, side light, transmitted light, etc.) to adapt to different detection requirements and help highlight the defects on the surface of the wafer. Optionally, as a feasible implementation method, the light source controller can also be combined with the shooting module to dynamically adjust the light source according to the real-time image data to optimize the image quality and detection effect. In addition, the control signal output by the motion computer can also control the rotation axis of the platform to rotate, thereby adjusting the position of the wafer to be detected, so that the camera can take pictures of it.

Furthermore, in a feasible implementation, the hardware configuration of the three-sided inspection station visual system of the inspection equipment can be equipped with an industrial line scan camera with a line frequency of 80kHZ, a 1.0X FA telecentric lens and an equal optical path optical mechanism. This configuration can achieve a field of view of 14.2mm and a detection accuracy of 3.5um.

When the camera is collecting images, the wafer to be inspected is loaded from the three-sided inspection platform, and the rotation axis (R axis) of the three-sided inspection platform carrying the wafer to be inspected rotates 360°. Before the R axis rotation starts, the camera mechanism control module in the motion computer sends a trigger signal to the light source controller, and the light source is triggered to light up. The light source controller sends a trigger signal to the camera at the same time when it lights up, and the camera starts to take pictures in the trigger mode.

Next, at step S323, in response to the shooting trigger signal of the light source controller, the camera is controlled to collect the image to be detected from the prism corresponding to the wafer to be detected based on the target objective lens. When the light source controller is ready to provide stable lighting for image acquisition, it will send a photo trigger signal to the camera. After the camera receives the photo trigger signal from the light source controller, it will start to take pictures. The target objective lens focuses the light onto the image sensor of the camera to ensure the clarity and details of the image. The prism can present the wafer surface of the corresponding viewing angle to the camera. The camera collects images from the light reflected by the prism corresponding to the wafer to be detected through the target objective lens. Each rotation of the R axis by 180° is a frame. When the platform R axis rotates 360° and stops, the camera completes the image acquisition and transmits it to the detection computer. In the subsequent process, the detection computer will perform detection calculation processing on the acquired image to be detected and output the detection result.

It should be noted that when the camera is collecting images, the detection equipment will automatically plan the corresponding photographing point trajectory according to the detected wafer size information, including wafer diameter, grain width and height, and wafer center point, and integrate the point trajectory with the image re-pasting algorithm to ensure that the images of adjacent photographing points have appropriate overlap. The motion computer can generate corresponding control signals based on the trajectory of the photographing points, so that the camera can set its photographing path in the optimal path while retaining the photographing area, thereby improving the automation of the detection equipment. Optionally, when generating the trajectory of the photographing points, you can start from the center point of the wafer and set the photographing points at certain intervals along the circumference, or divide the wafer surface into grids, and select a photographing point in each grid to ensure that the entire wafer surface is covered.

Next, as further shown in FIG3 , in step S330 , the image to be inspected captured by the camera is transmitted to the inspection computer, which performs calculations on it to determine the inspection result of the wafer to be inspected. Steps S310 and S330 may be the same or similar to steps S101 and S103 described above in conjunction with FIG1 , and will not be described in detail here.

FIG4 is a flow chart showing the determination of wafer defect detection results according to an embodiment of the present application. It can be seen from the following description that the wafer detection method based on the wafer detection system shown in FIG4 can be a specific manifestation of the method described in the foregoing text in combination with FIG1, so the description in the foregoing text can also be applied to the following description of each step of FIG4. As shown in FIG4, the wafer detection method based on the wafer detection system may include: at step S410, in response to the interactive information of the detection computer, switching the target objective lens and determining the target detection position based on the motion computer. At step S420, the motion computer sends a control signal to control the camera to collect the image to be detected at the target detection position based on the previously switched target objective lens and the prism of the wafer to be detected. Then, at step S430, the image to be detected collected by the camera will be transmitted to the detection computer, which will perform calculations on it to determine the detection result of the wafer to be detected.

In one embodiment, step S430 includes: at step S431, based on the detection computer, the image to be detected is allocated to the algorithm computer. In order to improve the detection efficiency, a distributed computing system is also used in this embodiment to perform computational processing on the image to be detected, that is, the image to be detected collected by the camera is transmitted to the detection computer, and the detection computer evenly and maximally allocates it to the algorithm computer. The algorithm computer is equivalent to the computing slave of the detection computer, and the number of the algorithm computer can be multiple. In a feasible implementation, when the detection computer allocates the image to be detected to the algorithm computer, it can adopt a sequential allocation method, or according to the current load of the algorithm computer, select the computing slave with the lightest load for allocation in turn.

Further, at step S432, the algorithm computer performs defect detection on the image to be detected and outputs the initial detection result. The algorithm computer can use a specific detection algorithm to perform calculation processing on the image to be detected. Referring to Figure 8, Figure 8 is a comparison diagram of the images detected by the algorithm computer, the left half is the image taken by the camera, and the right half is the detection result diagram. The red area and green area circled by the dotted line in the result diagram are the detected defects 1-defect 5. When the algorithm computer receives the image to be detected, the image to be detected can be pre-processed in advance to improve the accuracy of defect detection, and then the edge detection algorithm is used to identify whether there is a defective area on the edge of the wafer in the image, or the texture analysis algorithm is used to extract the texture features in the image to be detected, so as to distinguish between normal areas and defective areas.

Next, at step S433, based on the detection computer, the initial detection results are summarized to obtain the final detection results. The algorithm computer will transmit the initial detection results back to the detection computer, and the detection computer will summarize and process the initial detection results to determine the final result of this wafer defect detection. In addition, the images to be detected captured by the camera and the final detection results will also be saved, so that in the subsequent process, the defect information of each wafer, such as length, width, area, etc., can be queried offline in the traceability system. It should be noted that the initial detection results in this embodiment are only used to describe the predecessor of the final detection results after summary, and the "initial detection results" do not limit the detection results of this time to the detection results of the initial defect detection. In this embodiment, by adopting a distributed computing system, the detection computer distributes the images to be detected captured by the camera to multiple algorithm computers for calculation and processing, which can improve the detection efficiency and the overall utilization efficiency of wafer detection.

As further shown in FIG. 4 , step S410 and step S420 may be the same as or similar to step S101 and step S102 described above in conjunction with FIG. 1 , and are not described in detail here.

FIG5 is a flow chart showing a wafer detection method based on a wafer detection system according to another embodiment of the present application. It can be seen from the following description that the wafer detection method based on a wafer detection system shown in FIG5 can be another implementation method after the method described in FIG1 in the foregoing text. In one embodiment, the wafer detection method based on a wafer detection system includes: at step S510, in response to an automatic re-judgment instruction, the detection computer determines the defect location information according to the detection results. In this embodiment, the detection computer can analyze the detection results, and for wafers with uncertain defects, the automatic re-judgment process will be triggered, that is, the automatic re-judgment instruction will be triggered and responded to. The detection computer analyzes the defect area based on the detection results to further determine the actual location of the defect. In a feasible implementation, the detection computer can perform high-resolution local amplification of the image and use corresponding image processing technology to determine the defect location information.

Next, at step S520, the detection computer uses the defect position information as interactive information, executes the steps of switching the target lens and determining the target detection position based on the motion computer in response to the interactive information sent by the detection computer. The process is the same as the steps performed in Figure 1, including the detection computer selecting and switching the target lens, transmitting the defect position information to the motion computer, and the motion computer performing analysis to determine the target detection position. It can be understood that the Review camera is the one that performs the re-judgment image acquisition task, the motion computer adjusts the light source, triggers the shooting signal to enable the Review camera to perform image acquisition on the defect position, saves the image collected by the Review camera and returns it to the detection computer, which is then assigned to the algorithm computer for defect detection by the detection computer, and finally the algorithm computer feeds back the re-judgment result to the detection computer. It can be understood that the defect position included in the re-judgment can be multiple, and when the Review camera completes the image acquisition of the current defect position, it will feedback a signal to the motion computer, and the motion computer will transfer the next defect position for image acquisition.

In addition, each wafer has a unique corresponding identification code. Before the initial inspection, the wafer will be scanned by OCR (Optical Character Recognition). After that, the wafer image, inspection results, and measurement results will be stored in association with its identification code. The images collected and saved this time can also be used for offline re-judgment. When the operator wants to query the defect information of the wafer, the defect information of each unqualified chip on the wafer can be queried in the traceability system based on the wafer identification code, including length, width, area, etc.

In this embodiment, the inspection equipment can automatically re-evaluate wafers with uncertain defects through the Review camera. At the same time, the re-evaluated images will be saved in the backtracking system and support offline query, so that equipment users can understand defect information more conveniently and provide themselves with better process optimization direction.

FIG6 is a flow chart showing another wafer detection method based on a wafer detection system according to an embodiment of the present application. It can be seen from the following description that the wafer detection method based on a wafer detection system shown in FIG6 is another detection method that can be performed by the wafer detection method based on a wafer detection system of the present application. In one embodiment, the wafer detection method based on a wafer detection system includes: at step S610, in response to a pulse signal generated when a platform carrying a wafer to be detected moves, data sampling is performed on the wafer to be detected based on a sensor.

In this embodiment, the detection device also supports the wafer measurement function, and it is provided with a 3D measurement module, including a sensor module and a motion platform module. The wafer is transmitted on the motion platform, and the motion platform mechanism will generate a pulse signal when working. These pulse signals represent the moving distance or position change of the motion platform. The sensor can obtain the pulse signal generated when the platform moves. After each preset number of pulse signals, the sensor samples the data of the wafer to be detected. The data sampled by the sensor will also be transmitted to the detection computer. The detection computer processes the data information collected by the sensor and finally generates the measurement data of the wafer, including the size, height and thickness of the wafer. Optionally, the preset number of pulse signals can be set according to the actual situation of the platform movement, such as 20, which is not limited in this embodiment. In a feasible implementation, the hardware setting of the visual system of the 3D measurement module can be matched with a CHROCODILE CLS 2.0 (a sensor name) sensor, and a 0.6mm optical probe is configured. It adopts a direct detection method and a line spectrum confocal principle for measurement. The measurement range is 0.3um-650um, and the measurement accuracy can reach 0.1um.

Further, at step S620, the detection computer receives the data information sent back by the sensor. And, at step S630, the measurement data of the wafer to be detected is determined according to the data information. It is understandable that the sensor will record the height information, surface profile and other three-dimensional data of the wafer surface at each sampling point, and these data can reflect the subtle changes and overall shape characteristics of the wafer surface. The collected three-dimensional data can be transmitted to the detection computer through the serial port or network transmission in the form of original point cloud data or other three-dimensional data formats. Taking point cloud data as an example, the detection computer will process these point cloud data to generate a three-dimensional surface model of the wafer, which contains the height information and shape characteristics of the wafer surface. Referring to Figure 9, Figure 9 is a schematic diagram of the wafer 3D measurement effect. Based on the generated three-dimensional model, the detection computer can perform various measurement analyses, such as thickness measurement, shape analysis, surface roughness evaluation, etc. Finally, the detection computer will generate the measurement data of the wafer. These data can be used for wafer grading or to determine whether the wafer meets the specification requirements.

In this embodiment, the detection equipment can not only perform defect detection on the wafer, but also measure the wafer. The entire process does not require human intervention, which greatly improves the detection efficiency and reduces the secondary damage related to electrostatic discharge caused by traditional manual operations.

To facilitate understanding of the overall implementation scheme of the present application, the complete control flow of the wafer detection method based on the wafer detection system of the present application is explained in conjunction with FIG10. In the wafer detection method based on the wafer detection system shown in FIG10: after the detection equipment performs product material picking, edge positioning, and OCR code scanning on the wafer, the detection equipment will perform three-sided detection on the wafer to be detected. The detection computer selects and switches the target objective lens according to the detection requirements, and sends the interactive information containing the detection and photo position to the motion computer. After receiving it, the motion computer parses and determines the target detection position, and controls the movement of the platform mechanism based on this output control signal, adjusts the light source controller, and triggers the shooting signal. The detection camera performs image acquisition based on the target objective lens and prism, and the acquired image to be detected will be sent back to the detection computer after being saved, and the detection computer will assign it to the algorithm computer. The algorithm computer uses a specific detection algorithm to calculate and process the image to be detected, thereby obtaining the initial detection result and transmitting it to the detection computer. The detection computer summarizes and processes the initial detection results fed back by each algorithm computer to obtain the final detection result. For wafers with uncertain defects in the test results, the automatic re-judgment process will be triggered. The test computer determines the defect location information based on the test results and sends it to the motion computer. The motion computer triggers the shooting signal based on the defect location information after adjusting the light source based on the light source controller, and controls the Review camera to collect images at the defect location. The collected images to be tested will be transmitted to the test computer again. The test computer assigns them to the algorithm computer, which re-judges the defects of the images to be tested, and the test results obtained by the re-judgment will also be transmitted to the test computer by the algorithm computer. In addition, when the Review camera completes image acquisition, it will provide feedback to the motion computer, and then the motion computer will move to the next defect location to repeat the image acquisition task. The images collected by the Review camera can be saved and used for offline re-judgment.

After that, the wafers that have been inspected will be unloaded from the platform, and the front measurement will begin after the front inspection is completed. The platform movement of the inspection equipment triggers the pulse signal, and the sensor samples the data once every preset number of pulse signals, and sends the sampled data information back to the inspection computer, which processes it to obtain the measurement results of the wafer. The wafers that have been measured will be unloaded, and the inspection equipment completes the overall inspection process of the wafer.

11 is a system schematic diagram showing a wafer detection device for a wafer detection system according to an embodiment of the present application. System 110 may include a wafer detection device 111 for a wafer detection system according to an embodiment of the present application, as well as its peripheral devices and an external network, to implement the wafer detection method for a wafer detection system according to an embodiment of the present application described in conjunction with FIGS. 1 to 6 .

As shown in Figure 11, the wafer detection device 111 for wafer detection system may include a CPU 1111, which may be a general-purpose CPU, a dedicated CPU or other information processing and program execution unit. Further, the wafer detection device 111 for wafer detection system may also include a large-capacity memory 1112 and a read-only memory ROM 1113, wherein the large-capacity memory 1112 may be configured to store various types of data. In an embodiment of the present application, interactive information, target detection position, control signal, image to be detected, and detection result may be included. In addition, ROM 1113 may be configured to store the initialization of each functional module of the wafer detection device 111 for wafer detection system, the basic input/output driver of the system, and the data required for booting the operating system.

Furthermore, the system 110 may also include other hardware platforms or components, such as the tensor processing unit (TPU) 1114, the image processing unit (GPU) 1115, the field programmable gate array (FPGA) 1116, and the machine learning unit (MLU) 1117. It is understood that although a variety of hardware platforms or components are shown in the system 110, they are merely exemplary and not restrictive, and those skilled in the art may add or remove corresponding hardware according to actual needs.

The wafer detection device 111 for wafer detection system also includes a communication interface 1118, so that it can be connected to a local area network/wireless local area network (LAN/WLAN) 115 through the communication interface 1118, and then connected to a local server 116 or connected to the Internet ("Internet") 115 through the LAN/WLAN. Alternatively or additionally, the wafer detection device 111 for wafer detection system based on the embodiment of the present application can also be directly connected to the Internet or cellular network through the communication interface 1118 based on wireless communication technology, such as wireless communication technology based on the third generation ("3G"), the fourth generation ("4G") or the fifth generation ("5G") . In some application scenarios, the wafer detection device 111 for wafer detection system based on the wafer detection system can also access the server 118 of the external network and the possible database 119 as needed, so as to obtain various known information such as interactive information, and can store data such as images to be detected and detection results.

The peripheral equipment of the wafer detection device 111 based on the wafer detection system may include a display device 112, an input device 113 and a data transmission interface 114. In one embodiment, the display device 112 may include, for example, one or more speakers and/or one or more visual displays, which are configured to perform voice prompts and/or image video display on the operation process or final result of the test equipment of the present application. The input device 113 may include, for example, a keyboard, a capture camera, or other input buttons or controls, which are configured to receive input or user instructions for detecting the call status. The data transmission interface 114 may include, for example, a serial interface, a parallel interface or a universal serial bus interface ("USB"), a small computer system interface ("SCSI"), a serial ATA, a FireWire ("FireWire"), a PCI Express and a high-definition multimedia interface ("HDMI"), etc., which are configured for data transmission and interaction with other devices or systems. According to the scheme of the present application, the data transmission interface 114 can transmit interactive information, control signals, images to be detected, and detection results. The above-mentioned CPU 1111, mass storage 1112, read-only memory ROM 1113, TPU 1114, GPU 1115, FPGA 1116, MLU 1117 and communication interface 1118 of the wafer inspection device 111 for wafer inspection system based on the present application can be connected to each other through a bus 1119, and data interaction with peripheral devices is realized through the bus. In one embodiment, through the bus 1119, the CPU 1111 can control other hardware components and peripheral devices in the wafer inspection device 111 for wafer inspection system based on the wafer inspection system.

It should also be understood that any module, unit, component, server, computer, terminal or device that executes instructions of the examples of the present application may include or otherwise access computer-readable media, such as storage media, computer storage media or data storage devices (removable and/or non-removable) such as disks, optical disks or tapes. Computer storage media may include volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information, such as computer-readable instructions, data structures, program modules or other data.

The present application also discloses a computer-readable storage medium, in which program instructions are stored, and the program instructions are suitable for being loaded and executed by a processor: in response to the interactive information of the detection computer, the target objective lens is switched and the target detection position is determined based on the motion computer; in response to the control signal of the motion computer, the camera is controlled to collect the image to be detected based on the target objective lens and the prism of the wafer to be detected at the target detection position; the image to be detected is transmitted to the detection computer, and the detection result of the wafer to be detected is determined based on the detection computer. Based on this, when the scheme of the present application is embodied in the form of a software product (computer-readable storage medium), the software product can be stored in a memory, which can include several instructions to enable a computer device (such as a personal computer, a server or a network device, etc.) to perform some or all steps of the method described in the embodiment of the present application. The aforementioned memory may include, but is not limited to, various media that can store program codes, such as a U disk, a flash drive, a read-only memory ROM, a random access memory ("Random Access Memory", abbreviated as RAM), a mobile hard disk, a disk or an optical disk.

Although multiple embodiments of the present application have been listed and described herein, it is obvious to those skilled in the art that such embodiments are provided only by way of example. Those skilled in the art can think of many changes, modifications and alternatives without departing from the thought and spirit of the present application. It should be understood that in the process of practicing the present application, various alternatives to the embodiments of the present application described herein can be adopted. The attached claims are intended to limit the scope of protection of the present application, and therefore cover equivalents or alternatives within the scope of these claims.

Claims (10)

1. A wafer inspection method based on a wafer inspection system, characterized in that the wafer inspection system includes a detection computer, a motion computer, and a camera, including: In response to the interactive information of the detection computer, switching the target objective lens and determining the target detection position based on the motion computer; In response to the control signal of the motion computer, the camera is controlled to collect the image to be detected based on the target objective lens and the prism of the wafer to be detected at the target detection position, wherein the image to be detected includes the front image, the back image and the side image of the wafer to be detected; The image to be inspected is transmitted to the inspection computer, and the inspection result of the wafer to be inspected is determined based on the inspection computer. 2. The method of claim 1, wherein the step of switching the target lens in response to the interactive information of the detection computer and determining the target detection position based on the motion computer comprises: Based on the detection computer, selecting and switching the target objective lens according to the detection requirements in the interactive information; The interaction information is parsed based on the motion computer to determine the target detection position. 3. The method according to claim 1, wherein in response to the control signal of the motion computer, controlling the camera to collect the image to be detected based on the target objective lens and the prism of the wafer to be detected at the target detection position comprises: In response to the control signal of the motion computer, controlling the platform carrying the wafer to be inspected to move to the target inspection position; In response to the control signal of the motion computer, adjusting the light source of the light source controller and controlling the rotation axis of the platform to rotate; In response to a shooting trigger signal from the light source controller, the camera is controlled to collect the image to be inspected from the prism of the wafer to be inspected based on the target objective lens. 4. The method according to claim 1, wherein transmitting the image to be inspected to the inspection computer and determining the inspection result of the wafer to be inspected based on the inspection computer comprises: Based on the detection computer, the image to be detected is assigned to an algorithm computer; Based on the algorithm, the computer performs defect detection on the image to be detected and outputs an initial detection result; Based on the detection computer, the initial detection results are summarized to obtain the detection results. 5. The method according to claim 1, characterized in that before the control signal of the motion computer is responded to, the camera is controlled to collect the image to be detected based on the target objective lens and the prism of the wafer to be detected at the target detection position, further comprising: Based on the detection computer, a photographing point trajectory is generated according to the size information of the wafer to be detected; Based on the motion computer, the control signal is output according to the photographing point trajectory. 6. The method according to claim 1, characterized in that after transmitting the image to be inspected to the inspection computer and determining the inspection result of the wafer to be inspected based on the inspection computer, it further comprises: In response to the automatic re-judgment instruction, determining defect location information based on the inspection result by the inspection computer; The defect position information is used as interactive information, and the steps of switching the target objective lens and determining the target detection position based on the motion computer in response to the interactive information of the detection computer are executed. 7. The method according to any one of claims 1 to 6, characterized in that the method further comprises: In response to a pulse signal generated when a platform carrying a wafer to be inspected moves, data sampling is performed on the wafer to be inspected based on a sensor; Based on the detection computer, receiving the data information returned by the sensor; According to the data information, the measurement data of the wafer to be inspected is determined. 8. A wafer inspection device based on a wafer inspection system, characterized in that the wafer inspection device based on the wafer inspection system comprises: processor; A memory storing program instructions for wafer inspection based on a wafer inspection system, wherein when the program instructions are executed by the processor, the method according to any one of claims 1 to 7 is implemented. 9. A computer-readable storage medium, characterized in that the computer-readable storage medium stores computer program instructions for wafer detection based on a wafer detection system, and when the computer program instructions are executed by a processor, the method according to any one of claims 1-7 is implemented. 10. A wafer inspection system, characterized in that the wafer inspection system comprises: A detection computer is used to exchange information with the motion computer and the algorithm computer to determine the detection results; Motion computer, used to exchange information with the detection computer and control the camera, light source controller and platform mechanism; An algorithm computer, used for detecting the image to be detected and returning an initial detection result to the detection computer; A camera, used for collecting the image to be detected; The light source controller is used to adjust the light source to assist the camera in taking pictures.