A method, apparatus, system, device, and medium for semiconductor defect characterization

Abstract

The application discloses a method, device, system, equipment and medium for semiconductor defect characterization, comprising: obtaining a material type of a sample to be measured, wherein the sample to be measured is semiconductor material; adjusting the temperature of the sample to be measured based on the material type of the sample to be measured; and performing characterization on the sample to be measured after temperature adjustment based on a second harmonic characterization method.

Description

Technical Field

[0001] This invention relates to the field of semiconductors, and more particularly to a method, apparatus, system, device, and medium for characterizing semiconductor defects. Background Technology

[0002] Second harmonic generation (SHG), as a novel optical characterization method, has achieved significant results in the field of semiconductor defect characterization due to its advantages of speed, non-destructive nature, and simplicity. For Si materials, analyzing the variation of SHG intensity with azimuth angle under different polarization conditions can provide information on the Si interface and bulk material, and scanning can reveal the surface damage of Si. For wide bandgap materials such as GaN and SiC, analyzing the variation of SHG intensity with azimuth angle under different polarization conditions can provide information on non-uniform strain in the material, and scanning can reveal defects of different crystal forms on the material surface. For dielectrics on semiconductor materials, time-correlated second harmonic generation (TD-SHG) can provide information on the interface state density Dit and the fixed oxide charge Qox.

[0003] However, when using TD-SHG to characterize semiconductor materials, there is a certain time required from the laser incident on the sample to the detector receiving the saturated SHG signal, and scanning characterization requires testing a large number of data points, which increases the characterization time and is not conducive to integrating SHG characterization technology into the process line. Summary of the Invention

[0004] This application provides a method, apparatus, system, device, and medium for semiconductor defect characterization, which solves the technical problem in the prior art that requires a complex and costly second harmonic characterization system to improve the characterization speed, and achieves the effect of improving the second harmonic characterization speed at a lower cost and in a simpler way.

[0005] Firstly, this application provides the following technical solution through an embodiment of the application:

[0006] A method for characterizing semiconductor defects includes:

[0007] Obtain the material type of the sample to be tested, wherein the sample to be tested is a semiconductor material;

[0008] Adjust the temperature of the sample based on the material type of the sample to be tested;

[0009] The sample to be tested after temperature adjustment is characterized based on the second harmonic characterization method.

[0010] In one embodiment, adjusting the temperature of the sample to be tested based on the material type of the sample to be tested includes:

[0011] Based on the saturation time of the second harmonic signal of the sample under test under different temperature conditions, the temperature to which the sample under test needs to be adjusted is determined.

[0012] In one embodiment, adjusting the temperature of the sample to be tested includes:

[0013] The adjustment time for adjusting the temperature of the sample to be tested is determined based on the following formula:

[0014] T = T1 + T2

[0015] Where T is the adjustment time; T1 is the heating time, which is the time it takes for the sample to be tested to be adjusted to the required temperature; and T2 is the holding time, which is the time it takes for the sample to be tested to be maintained at the required temperature.

[0016] In one embodiment, T2 is twice T1.

[0017] In one embodiment, adjusting the temperature of the sample to be tested includes:

[0018] The temperature of the sample to be tested is adjusted using a temperature controller that is continuously adjustable in the range of 25℃ to 500℃.

[0019] In one embodiment, the step of basing the test sample material type includes:

[0020] The temperature of the sample under test is adjusted based on the material type of the substrate.

[0021] Secondly, through one embodiment of this application, the following technical solution is provided:

[0022] An apparatus for characterizing semiconductor defects, comprising:

[0023] An acquisition unit is used to acquire the material type of the sample to be tested, wherein the sample to be tested is a semiconductor material;

[0024] A temperature control unit is used to adjust the temperature of the sample to be tested based on the material type of the sample to be tested;

[0025] The characterization unit is used to characterize the sample to be tested after temperature adjustment based on the second harmonic characterization method.

[0026] In one embodiment, the temperature control unit is further configured to:

[0027] Based on the saturation time of the second harmonic signal of the sample under test under different temperature conditions, the temperature to which the sample under test needs to be adjusted is determined.

[0028] In one embodiment, the temperature control unit is further configured to:

[0029] The adjustment time for adjusting the temperature of the sample to be tested is determined based on the following formula:

[0030] T = T1 + T2

[0031] Where T is the adjustment time; T1 is the heating time, which is the time it takes for the sample to be tested to be adjusted to the required temperature; and T2 is the holding time, which is the time it takes for the sample to be tested to be maintained at the required temperature.

[0032] In one embodiment, the temperature control unit is further configured to:

[0033] T2 is twice that of T1.

[0034] In one embodiment, the temperature control unit is further configured to:

[0035] The temperature of the sample to be tested is adjusted using a temperature controller that is continuously adjustable in the range of 25℃ to 500℃.

[0036] In one embodiment, the temperature control unit is further configured to:

[0037] The temperature of the sample under test is adjusted based on the material type of the substrate.

[0038] Thirdly, through one embodiment of this application, the following technical solution is provided:

[0039] A system for characterizing semiconductor defects, comprising:

[0040] The device includes a characterization apparatus and a temperature control apparatus, wherein the temperature control apparatus is used to adjust the temperature of the sample to be tested, and the characterization apparatus is used to characterize the sample to be tested after the temperature has been adjusted.

[0041] The temperature control device includes a sample stage and a temperature controller; the characterization device includes a laser, a polarizer, a first objective lens, a second objective lens, an analyzer, a filter, and a detector; the laser emitted by the laser emitter passes sequentially through the polarizer and the first objective lens and is incident on the temperature-adjusted sample; the second harmonic reflected from the sample passes sequentially through the second objective lens, the analyzer, and the filter and is incident on the detector; so that the detector analyzes the second harmonic and obtains the characterization data of the sample.

[0042] Fourthly, through one embodiment of this application, the following technical solution is provided:

[0043] An electronic device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that the processor executes the computer program to implement the steps described in the first aspect.

[0044] Fifthly, the present invention provides the following technical solution through an embodiment of the present invention:

[0045] A computer-readable storage medium having a computer program stored thereon, characterized in that the computer program, when executed by a processor, implements the steps described in the first aspect.

[0046] One or more technical solutions provided in the embodiments of this application have at least the following technical effects or advantages:

[0047] This invention discloses a method, apparatus, system, device, and medium for semiconductor defect characterization. Before performing second harmonic characterization on the sample, the temperature of the sample is adjusted based on its material type. The sample absorbs heat, generating a large number of electrons and holes, thereby increasing the speed of second harmonic characterization. Therefore, it effectively solves the technical problem of the long time required for existing second harmonic characterization of semiconductors. It eliminates the need for an additional excitation light source to excite electrons and holes, thus achieving a faster, lower-cost, and simpler method to improve the speed of second harmonic characterization. Attached Figure Description

[0048] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0049] Figure 1 This is a flowchart of a semiconductor defect characterization method according to an embodiment of the present invention;

[0050] Figure 2 This is a schematic diagram illustrating the generation principle of time-related second harmonic TD-SHG in an embodiment of the present invention;

[0051] Figure 3 This is a time-dependent second harmonic TD-SHG signal diagram of 5nm SiO2 on a Si substrate in an embodiment of the present invention.

[0052] Figure 4 This is a time-dependent second harmonic TD-SHG signal diagram of Al2O3 at 15 nm on a Si substrate in an embodiment of the present invention.

[0053] Figure 5This is a schematic diagram illustrating the generation principle of time-dependent second harmonic TD-SHG with a temperature controller in an embodiment of the present invention.

[0054] Figure 6 This is a structural diagram of a semiconductor defect characterization device according to an embodiment of the present invention;

[0055] Figure 7 This is a structural diagram of a semiconductor defect characterization system according to an embodiment of the present invention;

[0056] Figure 8 This is a structural diagram of an electronic device according to an embodiment of the present invention;

[0057] Figure 9 This is a structural diagram of a computer-readable storage medium according to an embodiment of the present invention. Detailed Implementation

[0058] This application provides a method, apparatus, system, device, and medium for semiconductor defect characterization, which solves the technical problem in the prior art that requires a complex and costly second harmonic characterization system to improve the characterization speed, and achieves the effect of improving the second harmonic characterization speed at a lower cost and in a simpler way.

[0059] The technical solution of this application embodiment is to solve the above-mentioned technical problems, and the general idea is as follows:

[0060] A method for characterizing semiconductor defects includes:

[0061] Obtain the material type of the sample to be tested, wherein the sample to be tested is a semiconductor material;

[0062] Adjust the temperature of the sample based on the material type of the sample to be tested;

[0063] The sample to be tested after temperature adjustment is characterized based on the second harmonic characterization method.

[0064] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0065] First, it should be clarified that the term "and / or" in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0066] Example 1

[0067] Specifically, such as Figure 1As shown in the figure, this application provides a method for characterizing semiconductor defects, including:

[0068] Step S101: Obtain the material type of the sample to be tested, wherein the sample to be tested is a semiconductor material.

[0069] In the specific implementation process, such as Figure 2 The semiconductor material shown in the figure includes a dielectric layer 2 and a substrate layer 3. The substrate layer 3 can absorb the energy of laser 1 to generate a large number of electrons 5 and holes 4. Under the action of the initial interface electric field Edc6 introduced by the manufacturing process, electrons and holes will separate 7. After gaining energy from laser 1, electrons cross the interface barrier and are captured by defects 8 in the dielectric layer, and the interface electric field Edc6 will also change accordingly. As the defects 8 in the dielectric layer are gradually filled by electrons, the interface electric field Edc6 will gradually saturate. The intensity of the second harmonic SHG will also change with the change of the interface electric field Edc6 in this process. By detecting and recording the second harmonic SHG signal, the time-dependent second harmonic TD-SHG curve can be obtained, thereby obtaining information on the interface state density Dit and the fixed oxide charge Qox.

[0070] Step S102: Adjust the temperature of the sample to be tested based on the material type of the sample to be tested.

[0071] In practice, the materials of the substrate and dielectric layers of different semiconductors vary, and the intrinsic excitation temperatures for electrons and holes also differ depending on the substrate material. Generally, valence electrons in semiconductors are not as strongly bound as those in insulators. If they can obtain sufficient energy from the outside (such as light, temperature rise, electromagnetic field excitation, etc.), some valence electrons may break free from their covalent bonds and become nearly free electrons (simultaneously creating a hole). This is called intrinsic excitation. This is a thermal intrinsic excitation, and the average energy required is the band gap.

[0072] Therefore, the wider the bandgap of the substrate material, the higher the temperature of the sample under test can be adjusted. However, the adjusted temperature cannot exceed the melting point temperature of the constituent materials of the sample under test. For example, the melting points of silicon (Si), gallium nitride (GaN), and silicon carbide (SiC) are 1685K, 2791K, and 3103K, respectively.

[0073] Step S103: Based on the second harmonic characterization method, the sample to be tested after temperature adjustment is characterized.

[0074] In practical implementation, second harmonic spectroscopy (SHG), as a novel optical characterization method, has achieved significant results in the field of semiconductor defect characterization due to its advantages of speed, non-destructive nature, and simplicity. For Si materials, analyzing the variation of SHG intensity with azimuth angle under different polarization conditions can provide information on the silicon-Si interface and bulk material, and scanning mapping can reveal the surface damage of Si. For wide-bandgap materials such as gallium nitride (GaN) and silicon carbide (SiC), analyzing the variation of SHG intensity with azimuth angle under different polarization conditions can provide information on non-uniform strain in the material, and scanning mapping can reveal defects of different crystal forms on the material surface. For dielectrics on semiconductor materials, time-correlated second harmonic spectroscopy (TD-SHG) can provide information on the interface state density (Dit) and fixed oxide charge (Qox), and scanning mapping can obtain defect information in the dielectric of wafer-level semiconductor materials.

[0075] As an optional embodiment, step S102 further includes:

[0076] Based on the saturation time of the second harmonic signal of the sample under test under different temperature conditions, the temperature to which the sample under test needs to be adjusted is determined.

[0077] In practice, the optimal temperature will vary depending on the doping concentration, substrate / dielectric combination, and dielectric thickness on the substrate, making it impossible to provide a single optimal temperature value. For example... Figure 3 and Figure 4 As shown: it can be seen that the signal of 5nm SiO2 on the Si substrate saturates within 10s, and the signal of 15nm Al2O3 on the Si substrate saturates within 50s.

[0078] However, for different samples, the time-dependent second harmonic (TD-SHG) signal can be measured first at room temperature, and then the temperature can be changed to measure the TD-SHG signal at different temperatures. If the TD-SHG signal is always saturated at a certain temperature, or saturates in a very short time (0.1s, 1ms), then this temperature is the optimal temperature for the test sample.

[0079] As an optional embodiment, step S102 further includes:

[0080] The adjustment time for adjusting the temperature of the sample to be tested is determined based on the following formula:

[0081] T = T1 + T2

[0082] Where T is the adjustment time; T1 is the heating time, which is the time it takes for the sample to be tested to be adjusted to the required temperature; and T2 is the holding time, which is the time it takes for the sample to be tested to be maintained at the required temperature.

[0083] In practice, T2 is twice the time of T1, thus allowing the semiconductor substrate to generate sufficient electrons and holes in the shortest possible time. T2 can also be any time; this embodiment does not impose a specific limitation.

[0084] Specifically, after obtaining the optimal temperature for a certain type of sample, the sample can be directly heated to that temperature in the future. The heating time will not be long. For example, it only takes about 15 minutes to heat the sample from room temperature to 300℃ using a PW-800 heater. Of these 15 minutes, 5 minutes are used to raise the temperature to 299℃, and the remaining 10 minutes are used to stabilize the temperature. That is, the temperature jumps within the remaining 10 minutes may be 299-302℃, 300-301℃, 299-301℃, and 300℃.

[0085] As an optional embodiment, step S102 further includes:

[0086] The temperature of the sample to be tested is adjusted using a temperature controller that is continuously adjustable in the range of 25℃ to 500℃.

[0087] In the specific implementation process, such as Figure 5 As shown, substrate 3 absorbs heat 21 provided by temperature controller 20 to generate a large number of electrons 5 and holes 4, which are then excited into defects 8 in dielectric layer 2. Laser 1 only needs to excite a small number of electrons into the defect energy levels in dielectric layer 2. Figure 2 Compared to systems without a temperature controller 20, the substrate 3 absorbs the heat 21 from the temperature controller 20, which promotes the excitation of electron-hole pairs and excites a large number of electrons into defects in the dielectric layer 2, thereby improving the characterization speed.

[0088] As an optional embodiment, step S102 further includes:

[0089] The temperature of the sample under test is adjusted based on the material type of the substrate.

[0090] In the specific implementation process, the electrons and holes generated by the semiconductor absorbing heat mainly originate from the semiconductor substrate. Therefore, the temperature of the sample under test can be adjusted based on the material type of the substrate, thereby improving the speed of second harmonic characterization.

[0091] The technical solutions described in the embodiments of this application have at least the following technical effects or advantages:

[0092] This invention discloses a method for characterizing semiconductor defects. Before performing second harmonic characterization on the sample, the temperature of the sample is adjusted based on its material type. The sample absorbs heat, generating a large number of electrons and holes, thereby increasing the speed of second harmonic characterization. Therefore, this method effectively solves the technical problem of the long time required for existing second harmonic characterization of semiconductors. It eliminates the need for an additional excitation source to excite electrons and holes, thus achieving a faster, lower-cost, and simpler method to improve the speed of second harmonic characterization.

[0093] Example 2

[0094] Based on the same inventive concept, such as Figure 6 As shown, this embodiment provides a semiconductor defect characterization apparatus 600, including:

[0095] The acquisition unit 610 is used to acquire the material type of the sample to be tested, wherein the sample to be tested is a semiconductor material;

[0096] Temperature control unit 620 is used to adjust the temperature of the sample to be tested based on the material type of the sample to be tested;

[0097] The characterization unit 630 is used to characterize the sample to be tested after temperature adjustment based on the second harmonic characterization method.

[0098] Since the semiconductor defect characterization apparatus described in this embodiment is the apparatus used to implement the semiconductor defect characterization method in this embodiment of the invention, those skilled in the art can understand the specific implementation and various variations of the semiconductor defect characterization apparatus in this embodiment based on the semiconductor defect characterization method described in this embodiment of the invention. Therefore, how the semiconductor defect characterization apparatus implements the method in this embodiment of the invention will not be described in detail here. Any apparatus used by those skilled in the art to implement the semiconductor defect characterization method in this embodiment of the invention falls within the scope of protection of this invention.

[0099] The technical solutions described in the embodiments of this application have at least the following technical effects or advantages:

[0100] This invention discloses a semiconductor defect characterization apparatus. Before performing second harmonic characterization on the sample, the temperature of the sample is adjusted based on its material type. The sample absorbs heat, generating a large number of electrons and holes, thereby increasing the speed of second harmonic characterization. Therefore, it effectively solves the technical problem of the long time required for existing second harmonic characterization of semiconductors. It eliminates the need for an additional excitation light source to excite electrons and holes, thus achieving a faster, lower-cost, and simpler method to improve the speed of second harmonic characterization.

[0101] Example 3

[0102] Based on the same inventive concept, such as Figure 7 As shown, this embodiment provides a system for characterizing semiconductor defects, including:

[0103] The device includes a characterization apparatus and a temperature control apparatus, wherein the temperature control apparatus is used to adjust the temperature of the sample to be tested, and the characterization apparatus is used to characterize the sample to be tested after the temperature has been adjusted.

[0104] The temperature control device includes a sample stage 19 and a temperature controller 20; the characterization device includes a laser 9, a polarizer 10, a first objective lens 11, a second objective lens 13, an analyzer 14, a filter 15, and a detector 17; the laser 12 emitted by the laser emitter passes sequentially through the polarizer 10 and the first objective lens 11 and is incident on the temperature-adjusted sample 18; the second harmonic reflected by the sample 18 passes through the second objective lens 13, the analyzer 14, and the filter 15 16 times and is incident on the detector 17, so that the detector 17 analyzes the second harmonic and obtains the characterization data of the sample 18.

[0105] Since the semiconductor defect characterization system described in this embodiment is the system used to implement the semiconductor defect characterization method in the embodiments of the present invention, those skilled in the art can understand the specific implementation and various variations of the semiconductor defect characterization system in this embodiment based on the semiconductor defect characterization method described in the embodiments of the present invention. Therefore, how the semiconductor defect characterization system implements the method in the embodiments of the present invention will not be described in detail here. Any system used by those skilled in the art to implement the semiconductor defect characterization method in the embodiments of the present invention falls within the scope of protection of the present invention.

[0106] Example 4

[0107] Based on the same inventive concept, such as Figure 8 As shown, this embodiment provides an electronic device, including a memory 810, a processor 820, and a computer program 811 stored in the memory 810 and executable on the processor 820. When the processor 820 executes the computer program 811, it performs the following steps:

[0108] The material type of the sample to be tested is obtained, wherein the sample to be tested is a semiconductor material; the temperature of the sample to be tested is adjusted based on the material type of the sample to be tested; and the sample to be tested after temperature adjustment is characterized based on the second harmonic characterization method.

[0109] Since the electronic device described in this embodiment is the electronic device used to implement the semiconductor defect characterization method in the embodiments of this application, those skilled in the art can understand the specific implementation method and various variations of the electronic device in this embodiment based on the semiconductor defect characterization method described in the embodiments of this application. Therefore, how the electronic device implements the method in the embodiments of this application will not be described in detail here. Any electronic device used by those skilled in the art to implement the semiconductor defect characterization method in the embodiments of this application falls within the scope of protection of this application.

[0110] Example 5

[0111] Based on the same inventive concept, such as Figure 9 As shown, this embodiment provides a computer-readable storage medium 900 on which a computer program 910 is stored. When the computer program 910 is executed by a processor, it performs the following steps:

[0112] The material type of the sample to be tested is obtained, wherein the sample to be tested is a semiconductor material; the temperature of the sample to be tested is adjusted based on the material type of the sample to be tested; and the sample to be tested after temperature adjustment is characterized based on the second harmonic characterization method.

[0113] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0114] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for characterizing semiconductor defects, characterized in that, include: Obtain the material type of the sample to be tested, wherein the sample to be tested is a semiconductor material, and the semiconductor material includes a dielectric layer and a substrate layer; Based on the material type of the sample to be tested, the temperature of the sample to be tested is adjusted, including determining the temperature to which the sample needs to be adjusted based on the material type of the sample, and heating the sample to the determined temperature using a temperature controller, so that the substrate layer absorbs the heat provided by the temperature controller, generates electrons and holes, and excites them into the defects of the dielectric layer. Specifically, for different sample material types, the time-related second harmonic signal and its saturation time are measured at different temperatures. The temperature to which the sample needs to be adjusted is determined based on the saturation time of the second harmonic signal corresponding to the sample under different temperature conditions. The temperature controller is continuously adjustable within the range of 25℃-500℃. Based on the second harmonic characterization method, the defects of the test sample after temperature adjustment are characterized.

2. The method as described in claim 1, characterized in that, Adjusting the temperature of the sample to be tested includes: The adjustment time for adjusting the temperature of the sample to be tested is determined based on the following formula: T = T1 + T2 Where T is the adjustment time; T1 is the heating time, which is the time it takes for the sample to be tested to be adjusted to the required temperature; and T2 is the holding time, which is the time it takes for the sample to be tested to be maintained at the required temperature.

3. The method as described in claim 2, characterized in that, T2 is twice that of T1.

4. The method as described in claim 1, characterized in that, Adjusting the temperature of the sample based on its material type includes: The temperature of the sample under test is adjusted based on the material type of the substrate.

5. An apparatus for characterizing semiconductor defects, characterized in that, include: An acquisition unit is used to acquire the material type of the sample to be tested, wherein the sample to be tested is a semiconductor material, and the semiconductor material includes a dielectric layer and a substrate layer; A temperature control unit is used to adjust the temperature of the sample under test based on the material type of the sample under test. This includes determining the required temperature of the sample under test based on the material type of the sample under test, and heating the sample under test to the determined temperature using a temperature controller. This allows the substrate layer to absorb the heat provided by the temperature controller, generating electrons and holes, and exciting them into defects in the dielectric layer. For different sample material types, the time-related second harmonic signal and its saturation time are measured at different temperatures. The required temperature of the sample under test is determined based on the saturation time of the second harmonic signal corresponding to the sample under test under different temperature conditions. The temperature controller is continuously adjustable within the range of 25℃ to 500℃. The characterization unit is used to characterize defects in the sample to be tested after temperature adjustment based on the second harmonic characterization method.

6. A system for characterizing semiconductor defects, characterized in that, A method for performing semiconductor defect characterization according to any one of claims 1-4, the system comprising: The instrument includes a characterization device and a temperature control device, wherein the temperature control device is used to adjust the temperature of the sample to be tested, and the characterization device is used to characterize defects in the sample to be tested after the temperature is adjusted. The temperature control device includes a sample stage and a temperature controller; the characterization device includes a laser, a polarizer, a first objective lens, a second objective lens, an analyzer, a filter, and a detector; the laser emitted by the laser passes sequentially through the polarizer and the first objective lens and is incident on the sample to be tested after the temperature has been adjusted; the second harmonic reflected from the sample to be tested passes sequentially through the second objective lens, the analyzer, and the filter and is incident on the detector, so that the detector analyzes the second harmonic and obtains the characterization data of the sample to be tested.

7. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method described in any one of claims 1-4.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method described in any one of claims 1-4.

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