TWM648783U - Composite-type rapid annealing device - Google Patents

Abstract

A composite-type rapid annealing device, which includes two electrodes, a heating chamber, an induction heating device, and a dielectric heating device is disclosed. At least one workpiece is placed between the two electrodes and located in a chamber of the heating chamber. The induction heating device of the composite-type rapid annealing device performs an induction heating step on the workpiece. When the conductivity of the workpiece decreases due to temperature rise, the two electrodes can be used to heat the workpiece, and the dielectric heating device can also perform a dielectric heating step on the workpiece, thereby maintaining a certain heating rate of the workpiece.

Description

Compound rapid annealing device

The invention relates to an annealing device, in particular to a composite rapid annealing device.

Silicon carbide (SiC) has a wide bandgap, high breakdown electric field, high thermal conductivity and excellent chemical inertness, making it an important semiconductor material for manufacturing high-temperature, high-power and high-frequency devices. Ion implantation is an indispensable technology for manufacturing SiC semiconductor components. Simultaneous annealing (Annealing) is a necessary step to remove lattice damage and activate the implanted ions after ion implantation. For silicon carbide, post-ion implantation annealing at a temperature greater than 1,500 °C is required to achieve process effects.

Conventional annealing is usually performed in ceramic furnaces with resistance heating or low-frequency induction heating. However, ceramic furnaces have slow heating/cooling rates (20 °C/min), which makes it difficult to anneal silicon carbide at temperatures above 1,500 °C. Because if silicon carbide is exposed to temperatures exceeding 1,400 °C for a long time, the constituent materials on the surface of the substrate will sublimate and redeposit (commonly known as step bunching), causing the surface of the silicon carbide wafer (Wafer) to be rough. degree increases, which limits the maximum annealing temperature. This limitation on annealing temperature may result in insufficient activation of the implanted ions, resulting in higher contact and channel region resistance.

Therefore, in order to avoid the problem of surface degradation of silicon carbide wafers caused by traditional annealing technology due to too slow heating speed, the development of rapid annealing technology has become key. Although halogen lamp and laser technology can achieve rapid thermal processing, there are still some problems, such as the highest achievable annealing temperature, surface melting, high density of residual defects, and redistribution of implants.

On the other hand, silicon carbide can effectively absorb microwave energy. With a properly designed annealing system, microwaves can provide very fast heating and cooling rates of silicon carbide wafers and good control of the annealing time. Microwaves have the characteristics of selective heating, because microwaves are only absorbed by the semiconductor wafer and not by the surrounding environment, and the annealing heating rate is very fast. At the same time, during the annealing process, the temperature increase of the environment around the silicon carbide wafer is limited, and the cooling rate of the silicon carbide wafer can be very high after the microwave source is turned off. Compared with traditional annealing technology, using microwaves to anneal silicon carbide, the heating results of small-area silicon carbide wafers show that the heating rate can exceed 600 °C/s and the temperature can be as high as 2,000 °C.

However, the wavelength of microwave is short, and the energy distribution in the heating reaction cavity is uneven, which in turn causes the problem of uneven heating of the silicon carbide wafer. Especially when the area of the silicon carbide wafer increases, the volume of the heating reaction cavity expands, and the annealing heating The problem of uneven heating will be more serious. At the same time, the required microwave energy has also increased significantly, making the equipment more expensive.

In view of this, one purpose of this invention is to provide a composite rapid annealing device to solve many of the problems of the above-mentioned traditional technology.

When the silicon carbide wafer is heated by electromagnetic waves that generate an alternating magnetic field (Alternating Magnetic Field), eddy current (Eddy Current) can be generated to provide an induction heating (Induction Heating, or induction heating) effect. However, when the temperature exceeds 500 degrees K, the conductivity of the silicon carbide wafer will decrease rapidly, causing its resistivity to increase. Moreover, electromagnetic waves with an alternating electric field can also heat the silicon carbide wafer by generating a dielectric heating mechanism (or dielectric heating mechanism), in which the dielectric of the silicon carbide wafer Loss tangent will increase as the temperature rises. When the temperature rises to more than about 1,000 degrees Celsius, the dielectric loss tangent will increase rapidly and significantly. Therefore, this invention proposes a composite heating mechanism that combines an induction heating mechanism and a dielectric heating mechanism to heat a workpiece, such as a silicon carbide wafer.

In order to achieve the aforementioned purpose, this invention proposes a composite rapid annealing device, which includes: two electrodes, in which at least one object to be processed is placed between the two electrodes; a heating chamber having a chamber to accommodate at least the The object to be processed; an induction heating device for performing an induction heating step on the object to be processed in the heating chamber, wherein the induction heating device generates an eddy current in the object to be processed by generating an induced magnetic field, thereby heating the object to be processed; and a dielectric heating device for performing a dielectric heating step on the object to be processed in the heating chamber, wherein the dielectric heating device generates an electric field on the two electrodes, Thereby heating the object to be processed located between the two electrodes.

Wherein, the induction heating device performs the induction heating step on the object to be processed and the two electrodes in the heating chamber, thereby heating the object to be processed and the two electrodes.

Wherein, the induction heating device and the dielectric heating device perform the induction heating step and the dielectric heating step respectively simultaneously, sequentially, intermittently or alternately.

It further includes a Faraday shielding layer disposed on the heating cavity, and the induction heating device penetrates through the Faraday shielding layer to form the induced magnetic field in the chamber of the heating cavity.

Wherein, the Faraday shielding layer is a metal tube with a plurality of openings.

Wherein, the metal cylinder has a reflective surface to reduce radiation heat loss of the heating cavity.

Wherein, the reflective surface of the metal tube is further covered with a reflective layer.

Wherein, there is at least one barrier layer between the two electrodes and the object to be processed.

Wherein, the number of the objects to be processed is plural, and at least one barrier layer is disposed between the objects to be processed.

Wherein, one of the barrier layer and the object to be processed has a polycrystalline structure, and the other one of the barrier layer and the object to be processed has a single crystal structure.

Wherein, the induction heating device and the dielectric heating device perform the induction heating step and the dielectric heating step on the object to be processed and the barrier layer, thereby heating the object to be processed and the barrier layer.

Wherein, the object to be processed is a wafer.

Wherein, the object to be processed is selected from the group consisting of a conductive object and a non-conductive object.

Wherein, the material of the two electrodes is graphite.

Wherein, the induction heating device includes an inductance coil wound around the heating cavity, wherein the induction heating device applies a first AC electromagnetic signal with a first predetermined frequency to the inductance coil, thereby generating the induced magnetic field in the to-be-processed objects and the two electrodes.

Wherein, the first predetermined frequency ranges from 50 kHz to 200 kHz.

Wherein, the dielectric heating device applies a second AC electromagnetic signal with a second predetermined frequency, thereby generating the electric field on the two electrodes located on both sides of the object to be processed.

Wherein, the second predetermined frequency ranges from 10MHz to 900MHz.

Wherein, the dielectric heating device includes a radio frequency power supply and a matching device. The radio frequency power supply provides the second AC electromagnetic signal with the second predetermined frequency. The matching device is electrically connected between the radio frequency power supply and the two electrodes. to reduce the reflection of the second AC electromagnetic signal.

It further includes a gas input unit and an exhaust unit respectively connected to the chamber of the heating chamber to maintain the chamber of the heating chamber at a predetermined pressure.

Wherein, the predetermined pressure of the heating chamber ranges from 0.1 atm to 10 atm.

It further includes a measurement and control system, including a pressure detection unit and a controller. The pressure detection unit is used to measure the air pressure of the chamber of the heating chamber. The controller responds accordingly based on the value of the air pressure. Control the operation of the gas input unit and/or the air extraction unit.

Wherein, the measurement and control system also includes a pyrometer for measuring the temperature of the chamber of the heating chamber.

Wherein, the heating chamber includes a cavity, an upper cover and a lower cover, and the cavity is connected between the upper cover and the lower cover, thereby forming the chamber between the cavity, the upper cover and the lower cover.

Wherein, the heating cavity is made of quartz tube or ceramic tube.

Based on the above, the composite rapid annealing device of this invention has the following functions and advantages:

(1) Combining the induction heating mechanism and the dielectric heating mechanism, it can be used to heat conductive and non-conductive objects at the same time. For example, the induction heating mechanism can be used to increase the temperature of the silicon carbide wafer, and the temperature of the silicon carbide wafer can be increased due to When reducing the conductivity, the dielectric heating mechanism is used to increase the temperature of the silicon carbide wafer, so that the wafer maintains a certain heating rate.

(2) The induction heating mechanism can also increase the temperature of the electrode, so that when the conductivity of the silicon carbide wafer decreases due to the increase in temperature, the silicon carbide wafer can be continuously heated by the heating electrode to maintain a certain stability of the silicon carbide wafer. Heating rate.

(3) The electrode can be used as a carrying base and a heating base.

(4) The heating cavity has a metal cylinder that can be used as a reflective layer and as a Faraday shielding layer, which not only reduces the radiation heat loss of the heating cavity, but also allows the AC magnetic field to enter the heating cavity to generate eddy currents in the wafer.

(5) A barrier layer is located between the electrode and the wafer or between the wafers to prevent diffusion contamination. The barrier layer can also be used as a carrying base and a heating base.

In order to enable Jun Shen to have a better understanding of the technical characteristics and the technical effects that can be achieved by this invention, the following is a preferred embodiment and a detailed description.

In order to facilitate understanding of the technical features, content and advantages of this invention and the effects it can achieve, this invention is described in detail below with diagrams and in the form of expressions of embodiments. The purpose of the diagrams used is only They are for illustration and auxiliary instructions, and may not represent the true proportions and precise configurations of the creation after its implementation. Therefore, the proportions and configurations of the attached drawings should not be interpreted to limit the scope of rights in the actual implementation of this creation. In addition, to facilitate understanding, the same elements in the following embodiments are labeled with the same symbols for explanation.

In addition, unless otherwise noted, the terms used throughout the specification and patent application generally have the ordinary meanings of each term used in the field, the content disclosed herein, and the specific content. Certain terms used to describe the invention are discussed below or elsewhere in this specification to provide those skilled in the art with additional guidance in describing the invention.

The use of "first", "second", "third", etc. in this article does not specifically refer to the order or sequence, nor is it used to limit the present invention. It is only used to distinguish components described by the same technical terms. Or just an operation.

Secondly, if the words "include", "includes", "have", "contains", etc. are used in this article, they are all open terms, which means including but not limited to.

This invention is a composite rapid annealing device. Taking the object to be processed as a wafer (such as a silicon carbide wafer) as an example, the physical properties of silicon carbide are that during processing procedures such as heating, the conductivity drops rapidly at high temperatures. However, the electromagnetic wave dielectric absorption rate increases rapidly. In addition, other wafer materials also have similar or similar characteristics. Therefore, this creation adopts a composite heating mechanism, including the use of a medium-frequency induction heating (Induction Heating) mechanism to rapidly increase the wafer temperature. For a doped wafer, when its temperature rapidly rises to a certain value, its conductivity decreases rapidly, and its conductivity will vary with the temperature of the wafer due to different doping concentrations or types. Difference means change. Therefore, this creation adopts a composite heating mechanism, which also includes the use of a radio frequency power source to perform a dielectric heating (Dielectric Heating) mechanism on wafers whose conductivity drops rapidly to achieve the effect of rapid wafer annealing.

Please refer to Figures 1 to 5. Figure 1 is a schematic cross-sectional structural diagram of an implementation form of the composite rapid annealing device of this invention. Figure 2 is a schematic diagram of the three-dimensional structure of the Faraday shielding layer of the composite rapid annealing device of this invention. Figure 3 is a schematic diagram of the operation of the dielectric heating mechanism of the composite rapid annealing device of this invention. Figure 4 is a schematic diagram of the operation of the induction heating mechanism of the composite rapid annealing device of this invention. Figure 5 is a schematic flow chart of the composite heating process of the composite rapid annealing method of this invention. The composite rapid annealing device 10 of the present invention includes two electrodes 20, a heating chamber 30, an induction heating device 40 and a dielectric heating device 50, as shown in Figure 1 . The object to be processed is placed between two electrodes 20, for example. For example, the electrode 20 is used to carry an object to be processed. The object to be processed is, for example, a material whose conductivity decreases as the temperature increases, or a material whose conductivity changes as the temperature changes, such as the wafer 22 . The object to be processed may be, for example, a silicon carbide wafer 22 or a wafer 22 made of other materials (such as Si, SiGe, Ge, GaAs, GaN or InP), and may be a wafer at any stage in any semiconductor manufacturing process, and Regardless of whether or not the product to be processed is doped or what kind of substances it is doped with, it falls within the scope of protection claimed by this creation. However, the invention is not limited to this, and the object to be processed can also be other materials or objects, such as crystal ingots or any other objects that need to be heated. The material of the electrode 20 is, for example, graphite. When the wafer 22 is placed between the two electrodes 20, the electrode 20 can be used as a carrying base for the wafer 22 and at the same time as a heatable electrode (or heating base). )use. Therefore, the electrode 20 can also be made of other materials with similar or identical effects. Although this creation uses an object to be processed whose electrical conductivity will decrease as the temperature increases or whose electrical conductivity changes as the temperature changes as an illustrative example, it is not intended to limit the scope of the rights of this creation. That is to say, any object, regardless of whether its electrical conductivity (or conductivity) changes with temperature changes, as long as it can be heated using the composite rapid annealing device 10 of the present invention, falls within the scope of the claimed invention.

The composite rapid annealing device 10 of this invention performs a composite heating process on the wafer 22 in the heating chamber 30. This composite heating process includes the use of an induction heating mechanism (as shown in Figure 4) and a dielectric heating mechanism (as shown in Figure 4). shown in 3). The heating chamber 30 has a chamber 32 for accommodating the two electrodes 20 and the wafer 22 . In the composite heating process, the induction heating device 40 of the composite rapid annealing device of the present invention performs an induction heating step on the wafer 22 and the two electrodes 20 in the heating chamber 30 (as shown in step S10 of Figure 5 ). Among them, the induction heating device 40 generates an alternating magnetic field (Magnetic Field) by using a first alternating current electromagnetic signal (AC), and generates an induced magnetic field (Induced Magnetic Field) with changes in magnetic flux (Magnetic Flux, Φ). Eddy current ( _IEC ) flows in the wafer 22 and the two electrodes 20 (as shown in FIG. 4 ), thereby heating the wafer 22 and the two electrodes 20.

In the induction heating mechanism, for the object to be processed, the heating energy generated per unit volume can be expressed by the following equation: p = . in, is the conductivity of the material to be processed, 𝜔 = 2𝜋𝑓, 𝑓 = electromagnetic wave frequency, B is the intensity of the alternating magnetic field. For doped silicon carbide wafers to be processed, the electrical conductivity (i.e., 1/resistivity) will increase as the heating temperature rises. However, when the temperature exceeds 500 degrees K, for example, the electrical conductivity then decreases rapidly (i.e., the resistivity increases).

In the composite heating process of the composite rapid annealing device 10 of the present invention, the dielectric heating device 50 performs a dielectric heating step on the wafer 22 in the heating chamber 30 (as shown in step S20 of FIG. 5 ). The dielectric heating device 50 generates an electric field on the two electrodes 20 to heat the wafer 22 located between the two electrodes 20 . The number of wafers 22 may be one (as shown in Figure 3(B) and (C)) or a plurality of wafers (as shown in Figure 3(A)). In addition, at least one barrier layer 24 can be selectively provided between the two electrodes 20 and the wafer 22 and between the two adjacent wafers 22 according to actual needs (as shown in Figure 3 (A) and (B)), or The arrangement of the barrier layer 24 is omitted (as shown in FIG. 3(C) ), and the barrier layer 24 can also be selectively provided between two adjacent wafers 22 . The purpose of the barrier layer 24 is to prevent contamination phenomena such as cross-border diffusion of doping components due to temperature rise between the wafers 22 or between the wafers 22 and the electrodes 20 . The barrier layer 24 can also be used as a carrying base and a heating base for the wafer 22 . Among them, the barrier layer 24 can also be selectively made of materials that can be heated by the induction heating device 40 and the dielectric heating device 50 . Thereby, the induction heating device 40 and the dielectric heating device 50 can, for example, perform the induction heating step (S10) and the dielectric heating step (S20) on the wafer 22 and the barrier layer 24 at the same time, thereby heating the wafer 22 and the barrier layer 24. For example, if the material of the wafer 22 is a single crystal structure (eg, single crystal silicon carbide), the component of the barrier 24 is, for example, a polycrystalline structure (eg, polycrystalline silicon carbide), and vice versa. That is, the wafer 22 and the barrier 24 are made of different materials, for example. However, the invention is not limited to this. As long as the barrier layer 24 can exert a barrier effect, such as a diffusion barrier effect, no matter what material it is made of or whether it can be heated, it shall fall within the scope of protection claimed by the invention. In order to facilitate the explanation of the technical means and technical effects of this invention, this invention takes the object to be processed as a wafer 22 (such as a silicon carbide wafer) and the electrode 20 as a graphite electrode. However, any substance, object or structure can be processed by this invention. The creation of a composite rapid annealing device for heating falls within the scope of protection claimed by this creation. In the composite heating procedure, the induction heating device 40 and the dielectric heating device 50 are not limited to performing the induction heating step (step S10) and the dielectric heating step (step S20) respectively simultaneously, sequentially, intermittently or alternately.

The heating mechanism of the composite rapid annealing device of this creation adopts a medium-frequency induction heating mechanism. The reason is that there are two considerations for using a heating power source with high and low frequency electromagnetic fields. The first aspect is the efficiency of medium heating. The effect of high-frequency electromagnetic waves is more effective. The second aspect is to consider the penetration depth of electromagnetic waves. In addition to serving as the base of the silicon carbide wafer 22, the graphite electrode 20 is also a heating electrode. Its penetration depth for electromagnetic waves is less than 400 𝜇𝑚 when it is greater than 10 MHz. It can be used as an electrode material to make the upper and lower An alternating electric field is generated between the electrodes 20 without attenuating too much. For low-frequency electromagnetic waves, the penetration depth is greater than the entire heating base composed of graphite electrode 20 and silicon carbide wafer 22. In other words, the first AC electromagnetic signal of medium frequency can perform effective overall heating. In particular, graphite can withstand high temperatures and its induction heating mechanism has high efficiency, so the temperature of the heating base composed of the graphite electrode 20 and the silicon carbide wafer 22 can be quickly increased. However, although this invention uses a medium frequency electromagnetic field as an example, the scope of rights of this invention is not limited to this. As long as electromagnetic fields of any frequency can be applied to this invention to cause inductive heating of the graphite electrode 20 and the silicon carbide wafer 22, All belong to the scope of protection requested by this creation.

For example, in the early stage of the heating reaction, the present invention can quickly increase the temperature of the graphite electrode 20 and the silicon carbide wafer 22 through the induction heating mechanism. When the temperature of the silicon carbide wafer 22 is, for example, higher than 500 degrees K, the silicon carbide The conductivity decreases and the heating effect becomes worse. However, the electrode 20 made of graphite is still heated by induction, and its temperature can still maintain a certain heating rate. As the temperature rises, the dielectric loss tangent of silicon carbide continues to increase, improving the efficiency of dielectric heating. When the temperature rises to about 1,000 degrees Celsius, the dielectric loss tangent increases significantly, so the effect of dielectric heating can be accelerated.

Specifically, the induction heating device 40 includes, for example, an inductance coil 42 wound around the heating cavity 30 . The induction heating device 40 applies a first AC electromagnetic signal of a first predetermined frequency to the inductor coil 42 to generate an induced magnetic field on the wafer 22 and the two electrodes 20 . The inductor coil 42 is driven by an intermediate frequency AC power supply, and the first predetermined frequency ranges from approximately 50 kHz to 200 kHz, but is not limited thereto. In this embodiment, the heating chamber 30 may, for example, include a cavity 34 , an upper cover 36 and a lower cover 38 . The cavity 34 is connected between the upper cover 36 and the lower cover 38 , so that the cavity 34 , the upper cover 36 and the lower cover 38 A chamber 32 is formed therebetween. The inductor coil 42 is wound around the cavity 34 of the heating chamber 30 . In order to implement the induction heating mechanism, the cavity 34 of the heating cavity 30 is made of quartz or ceramic, for example. The radio frequency power supply 52 of the dielectric heating device 50 applies a second AC electromagnetic signal of a second predetermined frequency to the two electrodes 20 through the upper cover 36 and the lower cover 38. The upper cover 36 and the lower cover 38 are made of, for example, a metal layer 35 and a thermal insulation material layer. 37 composition. However, the present invention is not limited to this. In other feasible aspects, the heating chamber 30 of the present invention may also be entirely composed of quartz, ceramics or other materials.

In this invention, a reflective design can be optionally added to the heating cavity 30 to increase the reflectivity of infrared light to minimize radiation loss. For example, in this invention, a metal barrel 60 can be provided outside the cavity 34 of the heating chamber 30, as shown in Figures 1 and 2. The metal barrel 60 can be an optically polished metal barrel, which can serve as a reflective surface and can The reflective layer (eg, gold) 62 is selectively coated to increase the reflectivity of infrared light, thereby reducing the radiation heat loss caused by the heating base composed of the graphite electrode 20 and the silicon carbide wafer 22 at extremely high temperatures. . In addition, the present invention can also selectively add a plurality of openings 64 on the metal cylinder 60. The openings 64 are, for example, longitudinal openings (e.g., strip-shaped) and are distributed around the metal cylinder 60, whereby the metal cylinder 60 can be used as a Faraday shield layer 66 to facilitate the AC magnetic field generated by the induction heating device 40 to pass through the Faraday shield layer 66 and enter the chamber 32 of the heating chamber 30, so that the electrode 20 and the wafer 22 generate eddy current I _EC , as shown in Figure 4.

The dielectric heating device 50 is a radio frequency dielectric heating device (or radio frequency heating device), as shown in FIGS. 1 and 3 , which applies a second AC electromagnetic signal with a second predetermined frequency, so that the position on the wafer 22 An electric field is generated between the two electrodes 20 on both sides, thereby performing a dielectric heating step on the wafer 22 in the heating chamber 30, thereby maintaining a certain heating rate on the wafer 22. For example, the dielectric heating device 50 includes a radio frequency power supply 52, and optionally further includes a matching device 54. The radio frequency power supply 52 provides the second AC electromagnetic signal of the above-mentioned second predetermined frequency. The radio frequency power supply 52 is, for example, directly electrically connected to the two electrodes 20 or electrically connected to the two electrodes 20 via wires (not shown). The matching device 54 is electrically connected between the radio frequency power source 52 and the two electrodes 20 to reduce the reflection of the second AC electromagnetic signal. That is to say, the matching circuit of the matcher 54 is specially designed to adjust the impedance of the heating cavity 30 to match the radio frequency power supply 52 (eg, RF/microwave power supply) to reduce the reflection of electromagnetic waves (eg, RF or microwave). The selected frequency of the radio frequency power supply 52 is greater than 10 MHz. Considering the uniformity of electromagnetic field distribution, the frequency used is less than 900 MHz. That is to say, the second predetermined frequency ranges from 10MHz to 900MHz, but is not limited thereto, for example, from 10MHz to 400MHz, and the output power can be adjusted within the range of 1 kilowatt and above. It can be any numerical range or above in the above frequency range and power range. , lower limit endpoint value. The parameters of the inductor L and the capacitor C in the matching circuit of the matching device 54 can change as the operating conditions change to maintain good coupling conditions. The existing L and C components in the matching circuit of matcher 54 can be electronically tuned so there is no delay in the tuning response time and higher heating rates can be achieved. Impedance matching is critical to achieve rapid heating. The optimal design of the matching network varies depending on the application. Since a person with ordinary knowledge in the technical field to which this invention belongs should be able to understand how to implement the dielectric heating device 50 and how to use the matching circuit of the corresponding matcher 54 and the radio frequency power supply 52 based on the disclosure of this invention, no further details are described here.

Since this invention has both an induction heating mechanism and a dielectric heating mechanism, it can heat conductive objects (such as conductive wafers) and non-conductive objects (such as non-conductive wafers). The wafers composed of the group are subjected to rapid annealing processing. Although this invention uses non-conductive and conductive silicon carbide wafers as examples, it is not limited thereto. Moreover, because the electromagnetic field distribution of this invention is easy to control and adjust, it can be applied to the annealing process of multiple wafers. For large-sized silicon carbide wafers (for example, larger than 8 inches), the annealing system can be designed correspondingly based on the operating principle and structure of the hybrid rapid annealing device of this invention. In addition, it should be noted that although this invention takes as an example that the electrode 20 can carry the wafer 22 and can be heated by an induced magnetic field, the scope of rights of this invention is not limited to this. For example, the electrodes 20 of the present invention may also be not used to carry the wafer 22, such as being located on both sides of the wafer 22, such as the upper cover 36 and the lower cover 38 of the heating chamber 30 (as shown in FIG. 6 Feasible aspect), although this modified design cannot heat the silicon carbide wafer 22 by heating the electrode 20, it is still a feasible aspect of the present invention, and therefore still falls within the scope of the claimed invention. That is to say, as long as the electrode 20 can function when the dielectric heating device 50 applies an alternating electric field, it is applicable to the present invention and falls within the scope of protection claimed by the present invention.

The composite rapid annealing device 10 of the present invention can optionally include a gas input unit 72 and a gas extraction unit 74 connected to the chamber 32 of the heating chamber 30 via the air inlet pipe 73 and the exhaust pipe 75 respectively, so as to make the heating chamber 30 Chamber 32 is maintained at a predetermined pressure. Similarly, the composite rapid annealing device 10 of the present invention optionally includes a measurement and control system 70, which is an air pressure and air flow control system, including a pressure detection unit 76 and a controller 78. The pressure detection unit 76 is used to measure heating. The controller 78 controls the operation of the gas input unit 72 and/or the air extraction unit 74 accordingly according to the air pressure of the chamber 32 of the chamber 30 .

For example, the operating range of the above-mentioned air pressure and air flow control system is from 0.1 atmosphere to 10 atmosphere. The pressure of the gas is monitored by the pressure detection unit 76 . In addition, the gas input unit 72 injects gas into the chamber 32 of the heating chamber 30 through the air inlet pipe 73 according to the gas flow setting, and uses the air extraction unit 74 to remove the gas from the chamber 32 of the heating chamber 30 through the exhaust pipe 75 Exhaust, where the air extraction unit 74 is, for example, a vacuum pump. To be specific, in this invention, before gas is input into the chamber 32 of the heating chamber 30, the chamber 32 of the heating chamber 30 can be evacuated by the air extraction unit 74. After the chamber 32 of the heating chamber 30 is in a vacuum state, , and then use the gas input unit 72 to introduce the gas into the chamber 32 of the heating chamber 30 until the chamber 32 of the heating chamber 30 reaches a predetermined pressure. The predetermined pressure of the chamber 32 of the heating chamber 30 ranges from 0.1 atm to 10 atm, and can be any numerical range or upper and lower endpoint values within the predetermined pressure range. The above-mentioned gas can be, for example, pure gas such as nitrogen or argon, but any range that can make the chamber 32 of the heating chamber 30 reach the set gas and its predetermined pressure falls within the scope of the invention. In addition, the present invention can control and set the flow rate of the gas input by the gas input unit 72 through the controller 78, and cooperate with the operation of the exhaust unit 74 to maintain the chamber 32 of the heating chamber 30 at the above-mentioned predetermined pressure.

In addition, the above-mentioned measurement and control system optionally includes a pyrometer 79 for measuring the temperature of the chamber 32 of the heating chamber 30 . The pyrometer 79 is, for example, an infrared pyrometer, but is not limited thereto. Among them, the emissivity (Emissivity) of the wafer (such as silicon carbide material) measured by this creation using a blackbody radiation source is 0.74, and this emissivity value is input into the pyrometer 79, which can be used for all the technologies disclosed in this creation. Temperature measurement.

To sum up, the composite rapid annealing device of this invention has the following functions and advantages:

(1) Combining the induction heating mechanism and the dielectric heating mechanism, it can be used to heat conductive and non-conductive objects at the same time. For example, the induction heating mechanism can be used to increase the temperature of the silicon carbide wafer, and the temperature of the silicon carbide wafer can be increased due to When the conductivity is reduced, the silicon carbide wafer is heated by a dielectric heating mechanism.

(2) The induction heating mechanism can also increase the temperature of the electrode, so that when the conductivity of the silicon carbide wafer decreases due to the increase in temperature, the silicon carbide wafer can be continuously heated by the heating electrode to maintain a certain stability of the silicon carbide wafer. Heating rate.

(3) The electrode can be used as a carrying base and a heating base.

(4) The heating cavity has a metal cylinder that can be used as a reflective layer and as a Faraday shielding layer, which not only reduces the radiation heat loss of the heating cavity, but also allows the AC magnetic field to enter the heating cavity to generate eddy currents in the wafer.

(5) A barrier layer is located between the electrode and the wafer or between the wafers to prevent diffusion contamination. The barrier layer can also be used as a carrying base and a heating base.

The above is only illustrative and not restrictive. Any equivalent modifications or changes that do not depart from the spirit and scope of this creation shall be included in the appended patent application scope.

10: Compound rapid annealing device 20: Electrode 22: Wafer 24: Barrier layer 30: Heating chamber 32: Chamber 34: Chamber 35: Metal layer 36: Upper cover 37: Insulation material layer 38: Lower cover 40: Induction heating Device 42: Inductor coil 50: Dielectric heating device 52: Radio frequency power supply 54: Matcher 60: Metal cylinder 62: Reflective layer 64: Opening 66: Faraday shielding layer 70: Measurement and control system 72: Gas input unit 73: Input Air pipe fittings 74: Air extraction unit 75: Exhaust pipe fittings 76: Pressure detection unit 78: Controller 79: Pyrometer AC: AC electromagnetic signal Φ: Magnetic flux I _EC : Eddy current S10, S20: Steps

Figure 1 is a schematic cross-sectional structural diagram of an implementation form of the composite rapid annealing device of this invention.

Figure 2 is a schematic diagram of the three-dimensional structure of the Faraday shielding layer of the composite rapid annealing device of this invention.

Figure 3 is a schematic diagram of the operation of the dielectric heating mechanism of the hybrid rapid annealing device of this invention. Figures 3(A), (B) and (C) respectively show multiple wafers, a single wafer and no barrier. The appearance of the layers.

Figure 4 is a schematic diagram of the operation of the induction heating mechanism of the composite rapid annealing device of this invention.

Figure 5 is a schematic flow chart of the composite heating process of the composite rapid annealing method of this invention.

Figure 6 is a schematic cross-sectional structural diagram of another embodiment of the composite rapid annealing device of the present invention.

10: Compound rapid annealing device

20:Electrode

22:wafer

24: Barrier layer

30:Heating chamber

32: Chamber

34:Cavity

35:Metal layer

36: Upper cover

37:Thermal insulation material layer

38:Lower cover

40: Induction heating device

42:Inductor coil

50: Dielectric heating device

52:RF power supply

54: Matcher

60:Metal barrel

62: Reflective layer

66: Faraday mask

70: Measurement and control systems

72:Gas input unit

73:Intake fittings

74:Extraction unit

75:Exhaust pipe fittings

76: Pressure detection unit

78:Controller

79: Pyrometer

Claims (25)

A composite rapid annealing device, including: Two electrodes, in which at least one object to be processed is placed between the two electrodes; A heating chamber having a chamber for at least accommodating the object to be processed; An induction heating device is used to perform an induction heating step on the object to be processed in the heating chamber, wherein the induction heating device generates an eddy current in the object to be processed by generating an induction magnetic field, thereby heating the object to be processed. processed products; and A dielectric heating device for performing a dielectric heating step on the object to be processed in the heating chamber, wherein the dielectric heating device generates an electric field on the two electrodes to heat the object between the two electrodes. The object to be processed. The composite rapid annealing device as claimed in claim 1, wherein the induction heating device performs the induction heating step on the object to be processed and the two electrodes in the heating chamber, thereby heating the object to be processed and the two electrodes. The composite rapid annealing device as described in claim 1, wherein the induction heating device and the dielectric heating device respectively perform the induction heating step and the dielectric heating step simultaneously, sequentially, intermittently or alternately. The composite rapid annealing device as claimed in claim 1 further includes a Faraday shielding layer disposed on the heating chamber, and the induction heating device penetrates through the Faraday shielding layer to form the induced magnetic field in the chamber of the heating chamber. . The composite rapid annealing device as claimed in claim 4, wherein the Faraday shielding layer is a metal tube with a plurality of openings. The composite rapid annealing device as claimed in claim 5, wherein the metal cylinder has a reflective surface to reduce radiation heat loss of the heating cavity. The composite rapid annealing device as claimed in claim 6, wherein the reflective surface of the metal tube is further covered with a reflective layer. The composite rapid annealing device as claimed in claim 1, wherein there is at least one barrier layer between the two electrodes and the object to be processed. The composite rapid annealing device as claimed in claim 1, wherein the number of objects to be processed is plural, and at least one barrier layer is provided between the objects to be processed. The composite rapid annealing device as claimed in claim 8 or 9, wherein one of the barrier layer and the object to be processed has a polycrystalline structure, and the other of the barrier layer and the object to be processed has a single crystal structure. . The composite rapid annealing device as described in claim 8 or 9, wherein the induction heating device and the dielectric heating device perform the induction heating step and the dielectric heating step on the object to be processed and the barrier layer, thereby heating The object to be processed and the barrier layer. The composite rapid annealing device as claimed in claim 1, wherein the object to be processed is selected from the group consisting of a conductive object and a non-conductive object. The hybrid rapid annealing device as claimed in claim 1, wherein the object to be processed is a wafer. The composite rapid annealing device as claimed in claim 1, wherein the two electrodes are made of graphite. The composite rapid annealing device as claimed in claim 1, wherein the induction heating device includes an inductor coil wound around the heating cavity, and the induction heating device applies a first AC electromagnetic signal with a first predetermined frequency to the inductor. on the coil, thereby generating the induced magnetic field on the object to be processed and the two electrodes. The composite rapid annealing device as claimed in claim 15, wherein the first predetermined frequency ranges from 50 kHz to 200 kHz. The composite rapid annealing device as claimed in claim 1, wherein the dielectric heating device applies a second alternating current electromagnetic signal with a second predetermined frequency, thereby generating the electric field on both sides of the object to be processed. on both electrodes. The composite rapid annealing device as claimed in claim 17, wherein the second predetermined frequency ranges from 10 MHz to 900 MHz. The composite rapid annealing device as claimed in claim 17, wherein the dielectric heating device includes a radio frequency power supply and a matcher, the radio frequency power supply provides the second AC electromagnetic signal with the second predetermined frequency, and the matcher It is electrically connected between the radio frequency power source and the two electrodes to reduce the reflection of the second AC electromagnetic signal. The composite rapid annealing device as claimed in claim 1, further comprising a gas input unit and an exhaust unit respectively connected to the chamber of the heating chamber to maintain the chamber of the heating chamber at a predetermined pressure. . The composite rapid annealing device as claimed in claim 20, wherein the predetermined pressure of the chamber of the heating chamber ranges from 0.1 atm to 10 atm. The composite rapid annealing device as described in claim 20 further includes a measurement and control system, including a pressure detection unit and a controller. The pressure detection unit is used to measure the air pressure of the chamber of the heating chamber. , the controller correspondingly controls the operation of the gas input unit and/or the air extraction unit according to the value of the air pressure. The composite rapid annealing device as claimed in claim 22, wherein the measurement and control system further includes a pyrometer for measuring the temperature of the chamber of the heating chamber. The composite rapid annealing device as claimed in claim 1, wherein the heating chamber includes a cavity, an upper cover and a lower cover, and the cavity is connected between the upper cover and the lower cover, whereby the cavity, the upper cover The chamber is formed between the lower cover. The composite rapid annealing device as described in claim 24, wherein the heating chamber is made of quartz tube or ceramic tube.