WO2022126676A1 - Semiconductor detection device and detection method - Google Patents

Abstract

A semiconductor detection device and a detection method. The detection device comprises: a wafer carrying device (100) used for carrying a wafer (101) to be detected; an incident light system (200) used for emitting incident light (210) to said wafer (101), an included angle (α) being formed between the incident light (210) and a first direction (Z), the incident light (210) being reflected by said wafer (101) to form reflected light (220), and the first direction (Z) being a normal direction perpendicular to the surface of said wafer (101); an optical signal sorting system (300) used for sorting out a fundamental-wave optical signal (310) from the reflected light (220); a sensing system (400) used for receiving the fundamental-wave optical signal (310), and obtaining position information according to the fundamental-wave optical signal (310); and a control system (500) used for receiving the position information, and adjusting, in the first direction (Z), the height of the wafer carrying device (100) according to the position information. By means of the detection device and method, existing semiconductor detection devices are improved.

Description

Semiconductor testing device and testing method

This application claims the priority of the Chinese patent application filed on December 14, 2020 with the application number 2020114625032 and titled "Semiconductor Testing Device and Testing Method", the entire contents of which are incorporated into this application by reference.

technical field

The present invention relates to the field of semiconductor manufacturing, in particular to a semiconductor testing device and a testing method.

Background technique

In the semiconductor manufacturing process, it is easy to cause the device yield to drop due to defects in the process or materials, and to increase the production cost. In particular, as the critical dimensions of circuits continue to shrink, the requirements for process control are becoming more and more stringent.

In order to find and solve problems in time in the actual production process, it is necessary to carry out on-line and non-destructive inspection of products, and then use defect observation equipment such as electron microscopes to image defects and analyze elemental components. Among non-destructive defect detection devices, optical defect detection devices have been widely recognized and studied due to their high sensitivity and good applicability to batch testing.

However, the existing optical defect detection devices still need to be improved.

SUMMARY OF THE INVENTION

The technical problem solved by the present invention is to provide a semiconductor testing device and a testing method to improve the testing device.

In order to solve the above-mentioned technical problems, the technical solution of the present invention provides a semiconductor inspection device, comprising: a wafer carrying device for carrying a wafer to be tested; an incident light system for emitting incident light to the wafer to be tested, There is an included angle between the incident light and the first direction, the incident light is reflected by the wafer to be tested to form reflected light, and the first direction is a normal direction perpendicular to the surface of the wafer to be tested ; an optical signal sorting system for sorting out the fundamental wave optical signal from the reflected light; a sensing system for receiving the fundamental wave optical signal and obtaining position information according to the fundamental wave optical signal; a control system for receiving the position information, and adjusting the height of the wafer carrier in the first direction according to the position information.

Optionally, the sensing system includes: a first receiving module for receiving the fundamental wave optical signal; and a position signal reading module for acquiring the position information according to the received fundamental wave optical signal.

Optionally, the control system includes: a second receiving module, where the second receiving module is configured to receive the location information.

Optionally, the control system further includes: a first arithmetic unit, configured to calculate and acquire movement information according to the position information, where the movement information includes the height of the wafer to be tested in the first direction and a predetermined value. Set the height difference between heights.

Optionally, the control system further includes: a first position control unit, configured to receive the movement information, and move the wafer carrier in the first direction according to the movement information.

Optionally, the control system further includes: a comparison unit, configured to output an offset signal when the deviation between the position information and the preset position information exceeds a deviation range.

Optionally, the control system further includes: a second position control unit, configured to move the wafer carrier in the first direction according to the offset signal.

Optionally, the control system further includes: a feedback unit, configured to acquire movement information of the wafer carrier, and send incident light control information to the incident light system.

Optionally, the incident light system includes a monitoring unit for acquiring incident light information and feeding back the incident light information to the control system, where the incident light information includes first optical power; the sensing system It also includes: a power reading module, used for acquiring the second optical power according to the fundamental wave optical signal, and sending the second optical power to the control system; the control system further includes a second arithmetic unit for According to the first optical power and the second optical power, the linear optical properties of the material of the wafer to be tested are acquired.

Optionally, the optical signal sorting system is further configured to sort out harmonic optical signals from the reflected light; the control system includes a defect detection unit, configured to acquire the to-be-to-be-received optical signals according to the harmonic optical signals. Defect information on wafers.

Optionally, it further includes: a harmonic signal acquisition system, configured to acquire the harmonic optical signal and transmit the harmonic optical signal to the defect detection unit.

Optionally, the optical signal sorting system includes a dichroic mirror, which is used to pass the fundamental wave optical signal in the reflected light, and send the harmonic optical signal in the reflected light to the harmonic signal collection system. reflection, or for passing the harmonic light signal in the reflected light, and reflecting the fundamental wave light signal in the reflected light to the sensing system.

Optionally, the incident light system includes: a light source for emitting initial incident light; a modulation unit for modulating one or more of the light intensity, polarization parameter and focal length of the initial incident light to emit all the light. the incident light.

Optionally, the wafer carrier device includes: a carrier tray for carrying the wafer to be tested; a fixing device disposed on the carrier tray for fixing the wafer to be tested on the carrier tray; a mechanical moving component , which is used to drive the carrier plate to move.

Optionally, the fixing device is a vacuum suction cup or a buckle fixed on the edge of the carrying disc.

Optionally, it further includes: a focusing unit, configured to focus the incident light on the surface of the wafer to be tested or inside the wafer to be tested.

Optionally, it further includes: an optical collimation unit, configured to collimate the reflected light, and make the collimated reflected light incident on the optical signal sorting system.

Optionally, it further includes: a turning system, configured to turn the reflected light, and make the turned reflected light incident on the optical signal sorting system.

Optionally, the sensing system includes quadrant photodetectors.

Correspondingly, the technical solution of the present invention also provides a detection method using the above semiconductor detection device, comprising: providing a wafer to be tested; emitting incident light to the wafer to be tested, the incident light having a difference between the incident light and the first direction There is an included angle between them, the incident light is reflected by the wafer to be tested to form reflected light, and the first direction is the normal direction perpendicular to the surface of the wafer; the reflected light is obtained and divided from the reflected light. picking out the fundamental wave optical signal; acquiring the fundamental wave optical signal, and acquiring position information according to the fundamental wave optical signal; adjusting the height of the wafer to be tested in the first direction according to the position information.

Optionally, according to the position information, the method for adjusting the height of the wafer to be tested in the first direction includes: acquiring movement information according to the position information, where the movement information includes that the wafer to be tested is The height difference between the height in the first direction and the preset height; according to the movement information, move and adjust the height of the wafer to be tested in the first direction until the wafer to be tested is in the first direction. The height is the same as the preset height.

Optionally, according to the position information, the method for adjusting the height of the wafer to be tested in the first direction includes: providing preset position information and a deviation range; when the difference between the position information and the preset position information is When the deviation exceeds the deviation range, an offset signal is output; and the height of the wafer to be tested is moved and adjusted in the first direction according to the offset signal.

Optionally, according to the position information, the method for adjusting the height of the wafer to be tested in the first direction further includes: after the wafer to be tested finishes moving in the first direction, moving the wafer to be tested in the first direction again. The wafer to be tested emits incident light.

Optionally, the wafer to be tested includes: a substrate and a layer to be tested located on the surface of the substrate.

Optionally, the incident light has a first optical power; the detection method further includes: acquiring a second optical power of the fundamental wave optical signal; acquiring the to-be-measured optical power according to the first optical power and the second optical power Linear optical properties of the layer.

Optionally, the method further includes: sorting out harmonic light signals from the reflected light; and acquiring defect information of the wafer to be tested according to the harmonic light signals.

Compared with the prior art, the technical scheme of the present invention has the following beneficial effects:

In the semiconductor detection device provided by the technical solution of the present invention, on the one hand, through the optical signal sorting system and the sensing system, the fundamental wave optical signal can be sorted out from the reflected light formed by the reflection of the wafer to be tested, and according to the fundamental wave signal The wave optical signal obtains position information that can correspond to the current height of the wafer to be tested. Therefore, through the control system, the height of the wafer carrier device can be adjusted in the first direction according to the position information, thereby, It realizes the monitoring and adjustment of the height of the wafer to be measured during the focusing process. On the other hand, the incident light system can emit oblique incident light to the wafer to be tested, that is, the incident light has an included angle with the normal direction perpendicular to the surface of the wafer to be tested. The reflected light formed by the reflection of the circle is also inclined, that is, the reflected light can have an included angle with the normal direction perpendicular to the surface of the wafer to be tested, so that the optical signal sorting system can be above the surface of the wafer to be tested. The reflected light is acquired at other positions, and the optical signal sorting system can sort out the fundamental wave optical signal propagating at positions other than above the surface of the wafer to be tested according to the reflected light. Since the fundamental wave optical signal propagates at positions other than above the surface of the wafer to be tested, the sensing system can receive the fundamental wave optical signal and acquire position information according to the fundamental wave optical signal, while being disposed on the surface of the wafer to be tested Positions other than above allow more space above the surface of the wafer to be tested. In summary, through the semiconductor inspection device, while monitoring and adjusting the height of the wafer to be tested, the sensing system for detecting the height of the wafer to be tested can be installed at a position other than above the surface of the wafer to be tested, so that the The space above the surface of the wafer to be tested is made more abundant, thereby improving the semiconductor inspection apparatus.

Further, since the first optical power of the incident light is acquired through the monitoring unit, and the second optical power of the fundamental wave optical signal is acquired through the power reading module, the control system can pass the first optical power through the first optical signal. The second arithmetic unit obtains the linear optical characteristics of the material of the wafer to be measured according to the first optical power and the second optical power, so that the linear optical characteristics of the material of the wafer to be measured can be used for detecting the material to be measured. Wafer defects provide additional information, improving the accuracy of defect detection. At the same time, since the second optical power is obtained according to the fundamental wave optical signal, the sensing system can obtain the linear optical characteristic while obtaining the information position according to the same incident light, so as to provide the additional information, Thus, the detection efficiency of defect detection is improved.

Further, since the optical signal sorting system is also used to sort out harmonic optical signals from the reflected light, the control system is also used to obtain the defects of the wafer to be tested according to the harmonic optical signals Therefore, the semiconductor inspection device can monitor and adjust the height of the wafer to be tested and detect defects of the wafer to be tested according to the same light source, thereby improving the detection efficiency of defect detection.

Description of drawings

1 to 5 are schematic structural diagrams of a semiconductor inspection device according to an embodiment of the present invention;

6 is a schematic structural diagram of a semiconductor testing device according to another embodiment of the present invention;

7 is a schematic structural diagram of a semiconductor testing device according to another embodiment of the present invention;

FIG. 8 is a schematic flowchart of a detection method according to an embodiment of the present invention.

Detailed ways

As described in the background art, the existing optical defect detection devices still need to be improved.

In one embodiment, an optical defect detection device is provided. In the optical defect detection device, the height of the wafer to be tested is detected by disposing a height sensor above the surface of the wafer to be tested. The height of the wafer to be tested is detected, and the position of the wafer to be tested is adjusted to realize focus control.

However, the height sensor disposed above the surface of the wafer to be tested occupies a limited space above the surface of the wafer, resulting in a relatively large space limitation and low degree of freedom in the arrangement of components in the optical defect detection device.

In order to solve the above problems, the present invention provides a semiconductor testing device and a testing method, including: a wafer carrying device for carrying a wafer to be tested; an incident light system for emitting incident light to the wafer to be tested, the There is an included angle between the incident light and the first direction, the incident light is reflected by the wafer to be tested to form reflected light, and the first direction is a normal direction perpendicular to the surface of the wafer to be tested; an optical signal sorting system for sorting out the fundamental wave optical signal from the reflected light; a sensing system for receiving the fundamental wave optical signal and obtaining position information according to the fundamental wave optical signal; a control system for The position information is received, and based on the position information, the height of the wafer carrier is adjusted in the first direction. Thus, an improvement in the semiconductor inspection device is achieved.

In order to make the above objects, features and beneficial effects of the present invention more clearly understood, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

1 to 5 are schematic structural diagrams of a semiconductor inspection device according to an embodiment of the present invention.

First, please refer to FIG. 1, the semiconductor inspection device includes:

The wafer carrier 100 is used for carrying the wafer 101 to be tested;

The incident light system 200 is used to emit incident light 210 to the wafer 101 to be tested, the incident light 210 has an angle α with the first direction Z, and the incident light 210 passes through the wafer 101 to be tested The reflected light forms reflected light 220, and the first direction Z is the normal direction perpendicular to the surface of the wafer 101 to be tested;

an optical signal sorting system 300 for sorting out the fundamental wave optical signal 310 from the reflected light 220;

a sensing system 400, configured to receive the fundamental wave optical signal 310, and obtain position information according to the fundamental wave optical signal 310;

The control system 500 is configured to receive the position information, and adjust the height of the wafer carrier 100 in the first direction Z according to the position information.

On the one hand, through the optical signal sorting system 300 and the sensing system 400, the fundamental wave optical signal 310 can be sorted out from the reflected light 220 formed by the reflection of the wafer 101 to be tested, and the fundamental wave optical signal 310 can be obtained according to the fundamental wave optical signal 310. The position information of the current height of the wafer to be tested 101, therefore, through the control system 500, the height of the wafer carrier 100 can be adjusted in the first direction Z according to the position information, thereby achieving In the focusing process, the height of the wafer 101 to be tested is monitored and adjusted. On the other hand, the incident light system 200 can emit oblique incident light 210 to the wafer 101 under test, that is, the incident light 210 has an angle α with the normal direction perpendicular to the surface of the wafer 101 under test, Therefore, the reflected light 220 formed by the reflection of the wafer under test 101 is also inclined, that is, the reflected light 220 can have an included angle with the normal direction perpendicular to the surface of the wafer under test, so that the optical signal is sorted. The system 300 can obtain the reflected light 220 at positions other than the surface of the wafer 101 to be tested, and the optical signal sorting system 300 can sort out positions other than the surface of the wafer 101 to be tested according to the reflected light 220 Propagated fundamental optical signal 310 . Since the fundamental wave optical signal 310 propagates at a position other than above the surface of the wafer 101 to be tested, the sensing system 400 can receive the fundamental wave optical signal 310 and acquire the position information according to the fundamental wave optical signal 310, and at the same time, the sensor system 400 can be set on the Positions other than above the surface of the wafer to be tested 101 make the space above the surface of the wafer to be tested 101 more abundant. In conclusion, through the semiconductor inspection device, the height of the wafer 101 under test can be monitored and adjusted, and the sensing system 400 for detecting the height of the wafer under test 101 can be installed outside the surface of the wafer under test 101 position, so that the space above the surface of the wafer 101 to be tested is more abundant, thereby improving the semiconductor testing device.

The following will be described in detail with reference to the accompanying drawings.

1 and 2, the incident light system 200 includes: a light source 201 for emitting initial incident light 211; a modulation unit 202 for modulating optical parameters of the initial incident light 211 to emit incident light 210, There is an included angle α between the incident light 210 and the first direction Z. That is, the incident light 210 is inclined with respect to the first direction Z.

Specifically, the optical parameters include one or more of light intensity, polarization parameters and focal length.

Specifically, the included angle α is an angle greater than 0 degrees and less than 90 degrees. The specific included angle can be adjusted according to the configuration of the component structure in the semiconductor inspection device.

Specifically, in this embodiment, the light source 201 emits the initial incident light 211 , and then the modulation unit 202 modulates the optical parameters of the initial incident light 211 , thereby emitting the incident light 210 .

In other embodiments, the incident light system does not include a modulation unit, and directly emits the incident light through the light source.

In this embodiment, the light source 201 includes a laser transmitter. The laser transmitter includes a pulsed laser and the like.

Please continue to refer to FIG. 1 , the semiconductor inspection apparatus further includes: a focusing unit 610 for focusing the incident light 210 on the surface of the wafer 101 under test or inside the wafer under test 101 .

Specifically, the wafer to be tested 101 includes a substrate (not shown) and a layer to be tested (not shown) located on the surface of the substrate.

In this embodiment, the layer to be tested is a single-layer structure.

In other embodiments, the layer to be tested is a multilayer structure.

Specifically, the incident light 210 is focused on the surface of the wafer 101 to be tested by the focusing unit 610 , and the incident light 210 is reflected by the surface of the wafer to be tested to form the reflected light 220 .

In other embodiments, the layer to be tested is a multi-layer structure arranged along the first direction Z, and the layer to be tested has a reflective surface therein. Specifically, the focusing unit focuses the incident light into the layer to be measured, the layer to be measured has a reflective surface, and the incident light is reflected by the reflective surface of the layer to be measured to form reflected light. The reflective surface includes the interface between the multi-layer structures in the layer to be measured, or the surface of one or more structures patterned in the layer to be measured.

It should be noted that, due to the limitation of the device performance limit of the focusing unit 610, the focal depth during focusing is greater than the thickness of the layer to be measured in the first direction Z. Therefore, whether the sensing system 400 is formed according to the incident light passing through the surface of the layer to be measured The acquired position information can correspond to the current height of the wafer 101 to be tested according to the fundamental wave optical signal in the reflected light obtained from the test, or the fundamental wave optical signal in the reflected light formed according to the incident light passing through the layer to be tested.

In this embodiment, the layer to be tested is a transparent material.

In other embodiments, the material of the layer to be measured may also include both a transparent material and a non-transparent material, or the material of the layer to be measured is a non-transparent material.

In this embodiment, there is no other semiconductor structure between the substrate and the layer to be tested.

In other embodiments, the wafer to be tested further includes: one or more of a semiconductor layer, a dielectric layer and an interconnection layer between the substrate and the layer to be tested.

In this embodiment, the focusing unit 610 includes a focusing lens.

In other embodiments, the focusing unit may also be a curved mirror or the like.

Please continue to refer to FIG. 1 , the semiconductor detection device further includes: an optical collimation unit 620 for collimating the reflected light 220 and making the collimated reflected light 220 incident on the optical signal sorting system 300 .

Through the collimation of the reflected light 220 by the optical collimation unit 620, the signal accuracy of the reflected light 220 obtained by the optical signal sorting system 300 can be improved, so that the position information obtained by the sensing system 400 corresponds to the current pending Measuring the height of the wafer 101 is more accurate.

In this embodiment, the optical collimation unit 620 includes a slow-axis collimating mirror and a fast-axis collimating mirror.

Please continue to refer to FIG. 1 , the optical signal sorting system 300 is further configured to sort out harmonic light signals 320 from the reflected light 220 .

In this embodiment, the control system 500 further includes a defect detection unit 580 (as shown in FIG. 5 ), configured to acquire defect information of the wafer 101 under test according to the harmonic light signal 320 .

Since the optical signal sorting system 300 is also used for sorting out the harmonic light signal 320 from the reflected light 220 , the control system 500 further includes a defect detection unit 580 for sorting out the harmonic light signal 320 according to the harmonic light signal 320 . Obtain the defect information of the wafer under test 101. Therefore, the semiconductor inspection device can monitor and adjust the height of the wafer under test 101 according to the same light source, while detecting the defect of the wafer under test 101, thereby improving the The detection efficiency of defect detection is improved.

Specifically, in this embodiment, after the reflected light 220 is collimated by the optical collimation unit 620 , the optical signal sorting system 300 sorts the fundamental wave optical signal 310 from the collimated reflected light 220 and harmonic optical signal 320 .

The harmonic optical signal 320 includes: a second harmonic signal (Frequency doubled second harmonic generation signal) that is frequency multiplied by the fundamental wave optical signal 310 .

In this embodiment, the semiconductor detection device further includes: a harmonic signal acquisition system 700 for acquiring the harmonic optical signal 320 and transmitting the harmonic optical signal 320 to the control system 500 .

Specifically, in this embodiment, the optical signal sorting system 300 includes a dichroic mirror for passing the harmonic light signal 320 in the reflected light 220 and sending the fundamental wave light signal 310 in the reflected light 220 to the sensor System 400 reflects.

In another embodiment, as shown in FIG. 7 , the optical signal sorting system 301 includes a dichroic mirror, which is used to pass the fundamental wave optical signal 310 in the reflected light 220 and separate the harmonics in the reflected light 220 The wave optical signal 320 is reflected to the harmonic signal acquisition system 700 .

By choosing to use the optical signal sorting system 300 in FIG. 1 or the optical signal sorting system 301 in the embodiment shown in FIG. 7 , the propagation directions of the sorted fundamental wave optical signal 310 and the harmonic optical signal 320 can be made more flexible. , the flexibility of the position of the sensing system 400 and the harmonic signal acquisition system 700 in the semiconductor detection device is improved, thereby improving the flexibility of the structure design of the semiconductor detection device.

In another embodiment, as shown in FIG. 7 , the semiconductor detection device further includes: a turning system 800 for turning the reflected light 220 and making the turned reflected light 220 incident on the optical signal analyzer Picking system 301. By arranging the steering system in the semiconductor detection device, the arrangement of the optical path of the reflected light 220 is more flexible. Therefore, on the one hand, the positional flexibility of the sensing system 400 and the harmonic signal acquisition system 700 in the semiconductor detection device is improved; on the other hand, the structure of the semiconductor detection device can be made more compact, and the miniaturization. Specifically, the steering system includes several mirrors.

In other embodiments, the optical signal sorting system further includes a polarizer for passing the nonlinear optical signal with preset polarization parameters in the harmonic optical signal, so as to increase the type of defect detection, and realize monitoring and adjustment of the crystal to be tested. The height of the circle is improved, the detection efficiency of defect detection is improved, and the detection sensitivity of the semiconductor inspection device is improved.

Please refer to FIG. 3 , the sensing system 400 includes: a first receiving module 410 for receiving the fundamental wave optical signal 310 ; a position signal reading module 420 for acquiring position information according to the received fundamental wave optical signal 310 .

In this embodiment, the first receiving module 410 includes a signal receiving surface (not shown), the fundamental wave optical signal 310 is received by the signal receiving surface, and the position information is a 2-dimensional coordinate in a plane coordinate system , the plane where the plane coordinate system is located is the signal receiving surface. The position information can correspond to the current height H of the wafer to be tested 101 in the first direction Z.

Specifically, please refer to FIG. 1 , FIG. 3 and FIG. 4 . FIG. 4 shows the incident light 210 , the reflected light 220 and the fundamental wave light signal when the wafer 101 to be tested is at height H ₀ , height H ₁ and height H ₂ respectively. 310 is a schematic diagram of optical signal propagation, the fundamental wave optical signal 310 is received by the signal receiving surface, and then, the position signal reading module 420 reads the position of the centroid of the fundamental wave optical signal 310 on the information receiving surface, and obtains the position of the center of mass of the fundamental wave optical signal 310. When the fundamental wave optical signal 310 is received by the signal receiving surface, the position information of the centroid of the fundamental wave optical signal 310. That is, the position signal reading module 420 reads the 2-dimensional coordinates of the centroid of the fundamental wave optical signal 310 on the signal receiving surface.

When the wafer to be tested 101 is at different heights H, taking the height H ₀ , height H ₁ and height H ₂ shown in FIG. 4 as an example, the centroid of the fundamental wave optical signal 310 will be located at different positions on the signal receiving surface respectively That is, when corresponding to different heights H, the two-dimensional coordinates reflecting the position of the center of mass of the fundamental wave optical signal 310 are also different. Therefore, the position information read by the position signal reading module 420 can reflect the height of the wafer 101 to be tested. , so that the current height H of the wafer to be tested 101 in the first direction Z can be corresponding to the position information.

In this embodiment, the sensing system 400 includes quadrant photodetectors.

Please refer to FIG. 1 and FIG. 5 in combination, the control system 500 includes: a second receiving module 510 for receiving the location information.

In this embodiment, the control system 500 further includes: a first arithmetic unit 520, configured to calculate and acquire movement information A according to the position information, where the movement information A includes that the wafer 101 to be tested is in the first The height difference between the height H in one direction Z and the preset height.

Specifically, the control system 500 pre-stores correspondence information between the position information and the height H, and the correspondence information includes a corresponding model and the like. After acquiring the position information, the first operation unit 520 can perform an operation according to the corresponding relationship information to acquire the height between the height H of the wafer to be tested 101 in the first direction Z and the preset height Poor, that is, the movement information A.

In this embodiment, the control system 500 further includes: a first position control unit 530, configured to receive the movement information A, and move the crystal in the first direction Z according to the movement information A The circular carrier device 100 adjusts the height of the wafer carrier device 100 in the first direction Z to realize the adjustment of the height H of the wafer 101 to be tested.

In yet another embodiment, please refer to FIG. 6 , the control system 500 further includes: a comparison unit 550 for outputting an offset signal when the deviation between the position information and the preset position information exceeds the deviation range; The second position control unit 560 is configured to move the wafer carrier 100 in the first direction Z according to the offset signal.

Specifically, after the control system 500 receives the position information, the comparison unit 550 compares the position information with preset position information, which is preset with the wafer 101 to be tested. Height corresponds. When the deviation between the position information and the preset position information exceeds the deviation range, the comparison unit 550 outputs an offset signal. After receiving the offset signal, the second position control unit 560 controls the wafer carrier 100 to move toward the preset height of the wafer to be tested in the first direction Z.

In yet another embodiment, please continue to refer to FIG. 6 , the control system 500 further includes: a feedback unit 570 for acquiring movement information of the wafer carrier 100 and sending incident light to the incident light system 200 control information.

Specifically, the movement information includes the movement situation of the wafer carrier 100 in the first direction Z, and the movement situation includes: moving or stopping. When the wafer carrier 100 stops moving toward the preset height of the wafer to be tested, the feedback unit sends incident light control information to the incident light system 200, so that the incident light system 200 emits incident light again 210. Therefore, by controlling the wafer carrier 100 to move toward the preset height of the wafer to be tested in the first direction Z several times, the height H of the wafer to be tested 101 is adjusted, so that the height H of the wafer to be tested 101 is adjusted. The test wafer 101 is located at a predetermined height.

Please continue to refer to FIG. 2 , FIG. 3 and FIG. 5 , the incident light system 200 further includes a monitoring unit 203 for acquiring incident light information according to the incident light 210 and feeding back the incident light information to the control system 500 , The incident light information includes the first optical power; the sensing system 400 further includes: a power reading module 430, configured to acquire the second optical power according to the fundamental wave optical signal 310, and send the second optical power to the control system 500 ; the control system 500 further includes a second arithmetic unit 540 for acquiring linear optical properties of the material of the wafer 101 to be tested according to the first optical power and the second optical power.

Since the first optical power of the incident light 210 is acquired through the monitoring unit 203 , and the second optical power of the fundamental wave optical signal 310 is acquired through the power reading module 430 , the control system 400 can pass The second arithmetic unit 540 obtains the linear optical properties of the material of the wafer to be tested 101 according to the first optical power and the second optical power, so as to obtain the linear optical properties of the material of the wafer to be tested 101 , which can provide additional information for detecting the defects of the wafer 101 to be tested, and improve the accuracy of defect detection. At the same time, since the second optical power is obtained according to the fundamental wave optical signal 310, the sensing system 400 can obtain the linear optical characteristics while obtaining the information position according to the same incident light 210, so as to provide the The additional information, thereby, improves the detection efficiency of defect detection.

Specifically, in this embodiment, after acquiring the first optical power and the second optical power, the control system 500 can use the second computing unit 540 to calculate the difference between the second optical power and the first optical power according to the difference between the second optical power and the first optical power. ratio to obtain the linear optical reflectivity of the layer to be measured.

In this embodiment, the semiconductor inspection device further includes: an imaging unit (not shown) for acquiring imaging patterns at different positions on the surface of the wafer 101 to be tested.

In this embodiment, the control system further includes: an imaging computing unit (not shown), configured to acquire the plane of the wafer to be tested 101 on the reference plane according to the imaging patterns at different positions on the surface of the wafer to be tested 101 Position information, the reference plane is parallel to the surface of the wafer 101 to be tested; a third position control unit (not shown) is used to move the wafer in a direction parallel to the reference plane according to the plane position information The carrier device 100 is used to realize the alignment of the wafer to be tested 101 in a direction parallel to the reference plane.

Specifically, after the imaging unit acquires imaging patterns at different positions on the surface of the wafer to be tested 101 , the imaging computing unit can acquire the plane position information of the wafer to be tested 101 on the reference plane through the imaging patterns, and then controls the wafer carrying The device 100 is moved to the desired position for alignment in a direction parallel to the reference plane.

In this embodiment, the wafer carrying device includes: a carrying tray (not shown) for carrying the wafer 101 to be tested; a fixing device (not shown) disposed on the carrying tray for carrying the The test wafer 101 is fixed on the carrying tray; a mechanical moving component (not shown) is used to drive the carrying tray to move. The mechanical moving assembly can move the carrier tray to a designated position according to the information provided by the control system 500 . Specifically, the fixing device is a vacuum suction cup or a buckle fixed on the edge of the carrying disc.

Correspondingly, an embodiment of the present invention also provides a detection method using the above-mentioned semiconductor detection device for detection, please refer to FIG. 8 , including:

Step S1, providing a wafer to be tested;

In step S2, incident light is emitted to the wafer to be tested, the incident light has an angle with the first direction, the incident light is reflected by the wafer to be tested to form reflected light, and the first direction is the normal direction perpendicular to the wafer surface;

Step S3, acquiring reflected light, and sorting out the fundamental wave optical signal from the reflected light;

Step S4, acquiring the fundamental wave optical signal, and acquiring position information according to the fundamental wave optical signal;

Step S5, according to the position information, adjust the height of the wafer to be tested in the first direction.

A detailed description will be given below with reference to the accompanying drawings.

Please refer to FIG. 1 and FIG. 8 in conjunction with the wafer to be tested 101 .

Specifically, the wafer to be tested 101 includes: a substrate (not shown) and a layer to be tested (not shown) located on the surface of the substrate.

In this embodiment, the layer to be tested is a single-layer structure.

In other embodiments, the layer to be tested is a multilayer structure.

In other embodiments, the layer to be tested is a multi-layer structure arranged along the first direction Z, and the layer to be tested has a reflective surface therein.

In this embodiment, the layer to be tested is a transparent material.

In other embodiments, the material of the layer to be measured may also include both a transparent material and a non-transparent material, or the material of the layer to be measured is a non-transparent material.

In this embodiment, there is no other semiconductor structure between the substrate and the layer to be tested.

In other embodiments, the wafer to be tested further includes: one or more of a semiconductor layer, a dielectric layer and an interconnection layer between the substrate and the layer to be tested.

Please refer to FIG. 1 , FIG. 2 and FIG. 8 , emit incident light 210 to the wafer under test 101 , the incident light 210 has an angle α with the first direction Z, and the incident light 210 passes through the Reflection of the wafer under test 101 forms reflected light 220 .

Specifically, the included angle α is an angle greater than 0 degrees and less than 90 degrees.

In this embodiment, the method for emitting the incident light 210 includes: emitting the initial incident light 211 ; and modulating the optical parameters of the initial incident light 211 to emit the incident light 210 .

Specifically, the optical parameters include one or more of light intensity, polarization parameters and focal length.

In other embodiments, the incident light can also be directly emitted without modulation.

In this embodiment, the detection method further includes: focusing the incident light 210 on the surface of the wafer to be tested 101 or inside the wafer to be tested 101 .

Specifically, in this embodiment, the incident light 210 is focused on the surface of the wafer 101 to be tested, and the incident light 210 is reflected by the surface of the layer to be tested to form reflected light 220 .

In other embodiments, the incident light is focused in the layer to be measured, and the incident light is reflected by a reflective surface in the layer to be measured to form reflected light.

Please refer to FIG. 1 and FIG. 3 together, and sort out the fundamental wave optical signal 310 from the reflected light 220 .

In this embodiment, the detection method further includes: sorting out the harmonic light signal 320 from the reflected light 220 .

Specifically, in this embodiment, the method for sorting out the fundamental wave optical signal 310 and the harmonic optical signal 320 from the reflected light 220 respectively includes: passing the harmonic optical signal 320 in the reflected light 220 , and separating the reflected light 220 from the harmonic optical signal 320 . The fundamental wave optical signal 310 is reflected.

In another embodiment, please refer to FIG. 7 , the method for sorting out the fundamental wave optical signal 310 and the harmonic optical signal 320 from the reflected light 220 respectively includes: passing the fundamental wave optical signal 310 in the reflected light 220 , and The harmonic light signal 320 in the reflected light 220 is reflected.

The harmonic optical signal 320 includes: a second harmonic signal that is frequency multiplied by the fundamental wave optical signal 310 .

In other embodiments, the detection method further includes: polarizing the harmonic optical signal to form a nonlinear optical signal with preset polarization parameters.

In this embodiment, the detection method further includes: before sorting out the fundamental wave optical signal 310 from the reflected light 220 , collimating the reflected light 220 .

Methods of collimating the reflected light 220 include fast axis collimation and slow axis collimation.

In another embodiment, please refer to FIG. 7 , the detection method further includes: turning the reflected light 220 .

Please refer to FIG. 1 , FIG. 4 and FIG. 5 in combination to obtain the fundamental wave optical signal 310 , and obtain location information according to the fundamental wave optical signal 310 .

Specifically, in this embodiment, the position information is a 2-dimensional coordinate of the center of mass of the fundamental wave optical signal 310 in a plane coordinate system.

Taking the height H ₀ , height H ₁ and height H ₂ shown in FIG. 4 as an example, when corresponding to different heights H of the wafer 101 to be tested, the 2-dimensional coordinates of the position of the center of mass of the reflected fundamental wave optical signal 310 are also different, so that , the current height H of the wafer to be tested 101 in the first direction Z can be corresponding to the position information.

Please refer to FIG. 1 and FIG. 5 , according to the position information, adjust the height H of the wafer under test 101 in the first direction Z.

In this embodiment, according to the position information, the method for adjusting the height H of the wafer to be tested 101 in the first direction Z includes: calculating and acquiring movement information A according to the position information, the movement information A Including, the height difference between the height H of the wafer under test 101 in the first direction Z and the preset height; according to the movement information A, move and adjust the wafer under test in the first direction Z 101 until the height H of the wafer to be tested 101 in the first direction Z is consistent with the preset height. Thus, adjustment of the height H of the wafer to be measured 101 is achieved.

Specifically, the correspondence information between the position information and the height H of the wafer 101 to be tested is provided, and the correspondence information includes a corresponding model and the like. After the location information is acquired, an operation is performed according to the correspondence information to acquire the height difference between the height H of the wafer to be tested 101 in the first direction Z and the preset height, that is, the movement information A. Next, according to the movement information A, the wafer to be tested 101 is moved in the first direction Z.

In yet another embodiment, please refer to FIG. 6 , according to the position information, the method for adjusting the height H of the wafer under test 101 in the first direction Z includes: providing preset position information and a deviation range; when When the deviation between the position information and the preset position information exceeds the deviation range, an offset signal is output; the height H of the wafer 101 to be tested is adjusted by moving in the first direction Z according to the offset signal.

In yet another embodiment, please continue to refer to FIG. 6 , according to the position information, the method for adjusting the height H of the wafer under test 101 in the first direction Z further includes: when the wafer under test 101 is After finishing the movement in the first direction Z, incident light is emitted to the wafer 101 under test again. Therefore, by adjusting the height H of the wafer to be tested 101 several times, the wafer to be tested 101 reaches a preset height.

In this embodiment, the detection method further includes: acquiring defect information of the wafer to be tested 101 according to the harmonic light signal 320 .

Please continue to refer to FIG. 2 , FIG. 3 and FIG. 5 , the incident light has a first optical power; the detection method further includes: acquiring the second optical power of the fundamental wave optical signal 310 ; according to the first optical power and the second optical power to obtain linear optical properties of the layer to be measured.

Specifically, after acquiring the first optical power and the second optical power, the linear optical reflectivity of the layer to be measured can be acquired according to the ratio of the second optical power to the first optical power.

In this embodiment, the detection method further includes: acquiring imaging patterns at different positions on the surface of the wafer to be tested 101; According to the plane position information, the reference plane is parallel to the surface of the wafer to be tested 101; according to the plane position information, the wafer to be tested 101 is moved in a direction parallel to the reference plane, so that the wafer to be tested 101 is moved Alignment of circle 101 in a direction parallel to the reference plane.

Although the present invention is disclosed above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be based on the scope defined by the claims.

Claims (26)

A semiconductor testing device, characterized in that it includes: a wafer carrier device for carrying the wafer to be tested; The incident light system is used to emit incident light to the wafer to be tested, the incident light has an included angle with the first direction, and the incident light is reflected by the wafer to be tested to form reflected light, and the incident light forms reflected light. The first direction is a normal direction perpendicular to the surface of the wafer to be tested; an optical signal sorting system for sorting out the fundamental wave optical signal from the reflected light; a sensing system, configured to receive the fundamental wave optical signal, and obtain position information according to the fundamental wave optical signal; The control system is configured to receive the position information, and adjust the height of the wafer carrier in the first direction according to the position information. The semiconductor detection device according to claim 1, wherein the sensing system comprises: a first receiving module for receiving the fundamental wave light signal; and a position signal reading module for receiving the fundamental wave light signal according to the received fundamental wave light signal to obtain the location information. The semiconductor testing device according to claim 2, wherein the control system comprises: a second receiving module, wherein the second receiving module is configured to receive the position information. The semiconductor testing device according to claim 3, wherein the control system further comprises: a first arithmetic unit, configured to calculate and acquire movement information according to the position information, the movement information comprising: The height difference between the height of the wafer in the first direction and the preset height. The semiconductor inspection device according to claim 4, wherein the control system further comprises: a first position control unit for receiving the movement information, and according to the movement information, in the first direction Move the wafer carrier. The semiconductor detection device according to claim 3, wherein the control system further comprises: a comparison unit, configured to output an offset signal when the deviation between the position information and the preset position information exceeds a deviation range . 6. The semiconductor inspection apparatus of claim 6, wherein the control system further comprises: a second position control unit for moving the wafer carrier in the first direction according to the offset signal . 7. The semiconductor inspection device according to claim 7, wherein the control system further comprises: a feedback unit for acquiring movement information of the wafer carrier device and sending incident light control information to the incident light system . The semiconductor inspection device according to claim 1, wherein the incident light system comprises a monitoring unit for acquiring incident light information and feeding back the incident light information to the control system, the incident light information including the first optical power; the sensing system further includes: a power reading module, configured to obtain the second optical power according to the fundamental wave optical signal, and send the second optical power to the control system; the The control system further includes a second arithmetic unit for acquiring linear optical properties of the material of the wafer to be tested according to the first optical power and the second optical power. The semiconductor inspection device according to claim 1, wherein the optical signal sorting system is further configured to sort out harmonic light signals from the reflected light; the control system comprises a defect detection unit for Defect information of the wafer to be tested is acquired according to the harmonic optical signal. The semiconductor inspection device according to claim 10, further comprising: a harmonic signal acquisition system, configured to acquire the harmonic optical signal and transmit the harmonic optical signal to the defect detection unit. The semiconductor detection device according to claim 11, wherein the optical signal sorting system comprises a dichroic mirror for passing the fundamental wave optical signal in the reflected light and separating harmonics in the reflected light. The wave light signal is reflected to the harmonic signal acquisition system, or used to pass the harmonic light signal in the reflected light, and reflect the fundamental wave light signal in the reflected light to the sensing system. The semiconductor detection device according to claim 1, wherein the incident light system comprises: a light source for emitting initial incident light; a modulation unit for modulating light intensity, polarization parameter and focal length of the initial incident light one or more of these to emit the incident light. The semiconductor testing device according to claim 1, wherein the wafer carrying device comprises: a carrying tray for carrying the wafer to be tested; a fixing device disposed on the carrying tray for carrying the wafer to be tested The circle is fixed on the carrying plate; a mechanical moving component is used to drive the carrying plate to move. 15. The semiconductor inspection device according to claim 14, wherein the fixing device is a vacuum suction cup or a buckle fixed on the edge of the carrier plate. The semiconductor inspection device according to claim 1, further comprising: a focusing unit for focusing the incident light on the surface of the wafer to be tested or inside the wafer to be tested. The semiconductor detection device according to claim 1, further comprising: an optical collimation unit for collimating the reflected light, and making the collimated reflected light incident on the optical signal sorting system. The semiconductor detection device according to claim 1, further comprising: a turning system for turning the reflected light and making the turned reflected light incident on the optical signal sorting system. The semiconductor inspection apparatus of claim 1, wherein the sensing system includes a quadrant photodetector. A detection method using the semiconductor detection device according to any one of claims 1 to 19, characterized in that, comprising: Provide wafers to be tested; Incident light is emitted to the wafer to be tested, the incident light has an angle with the first direction, the incident light is reflected by the wafer to be tested to form reflected light, and the first direction is perpendicular to The normal direction of the wafer surface; acquiring reflected light, and sorting out the fundamental wave optical signal from the reflected light; acquiring the fundamental wave optical signal, and acquiring location information according to the fundamental wave optical signal; According to the position information, the height of the wafer to be tested is adjusted in the first direction. 21. The detection method according to claim 20, wherein, according to the position information, the method for adjusting the height of the wafer to be tested in the first direction comprises: acquiring movement information according to the position information, the movement The information includes the height difference between the height of the wafer to be tested in the first direction and the preset height; according to the movement information, move and adjust the height of the wafer to be tested in the first direction until the height of the wafer to be tested is adjusted. The height of the wafer to be tested in the first direction is consistent with the preset height. The detection method according to claim 20, wherein, according to the position information, the method for adjusting the height of the wafer to be tested in the first direction comprises: providing preset position information and a deviation range; When the deviation between the position information and the preset position information exceeds the deviation range, an offset signal is output; the height of the wafer to be tested is moved and adjusted in the first direction according to the offset signal. 22. The detection method according to claim 22, wherein, according to the position information, the method for adjusting the height of the wafer to be tested in the first direction further comprises: when the wafer to be tested ends in the After the movement in the first direction, incident light is again emitted to the wafer to be tested. 21. The detection method according to claim 20, wherein the wafer to be tested comprises: a substrate and a layer to be tested located on the surface of the substrate. The detection method according to claim 24, wherein the incident light has a first optical power; the detection method further comprises: acquiring a second optical power of the fundamental wave optical signal; according to the first optical power and the second optical power to obtain linear optical properties of the layer to be measured. The detection method according to claim 20, further comprising: sorting out harmonic light signals from the reflected light; and acquiring defect information of the wafer to be tested according to the harmonic light signals.

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