IGZO film quality evaluation method and electronic equipment

Abstract

The invention relates to the technical field of evaluation of microstructures and electrical properties of semiconductor materials, and particularly discloses an IGZO film quality evaluation method and electronic equipment, and the method comprises the steps: carrying out the pretreatment of a silicon substrate; imaging the IGZO film sample by using an optical microscope, and carrying out microstructure analysis on the image content; carrying out electrical property comprehensive test on the IGZO thin film sample; calculating the comprehensive quality index QI of the IGZO thin film sample by combining the microstructure analysis result and the electrical property test data obtained for the IGZO thin film sample; and optimizing the production process of the IGZO film by adopting a control variable method according to the comprehensive quality index QI. According to the IGZO thin film quality evaluation method and the electronic equipment provided by the embodiment of the invention, comprehensive evaluation on the microstructure and the electrical property of the IGZO thin film is realized by combining optical microscope image analysis and multi-parameter electrical property test. According to the method, the IGZO film quality evaluation process is simplified, and powerful data support is provided for optimizing the preparation process and improving the film performance.

Description

Technical Field

[0001] The invention relates to the technical field of microstructure and electrical performance evaluation of semiconductor materials, and in particular to an IGZO film quality evaluation method and an electronic device. Background Art

[0002] IGZO thin films have shown great potential in display technology, sensors, and solar cells due to their high transparency and excellent electronic properties. However, small differences in the quality of IGZO thin films can have a significant impact on performance. Existing quality assessment methods often focus on one aspect of performance and lack a comprehensive and integrated assessment of the film's microstructure and electrical properties. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems in the related art to a certain extent. To this end, the purpose of the present invention is to provide an IGZO film quality evaluation method and electronic device, which provides a comprehensive and accurate evaluation method for the preparation process optimization and quality control of the IGZO film by combining optical microscope image analysis with multi-parameter electrical performance testing.

[0004] To achieve the above object, a first embodiment of the present invention provides a method for evaluating the quality of an IGZO thin film, the method comprising:

[0005] Pre-treating a silicon substrate, and using the pre-treated silicon substrate to prepare an IGZO thin film sample;

[0006] The IGZO film samples were imaged using an optical microscope and the image content was analyzed for microstructure to evaluate the structural quality and uniformity of the IGZO film.

[0007] Conduct comprehensive electrical performance tests on IGZO thin film samples, including using a four-point probe method to measure the resistivity of the thin film samples, a capacitance-voltage test system to measure the dielectric constant and dielectric loss of the thin film samples, and a Hall effect measurement system to determine the carrier concentration and mobility of the thin film samples;

[0008] Combined with the above microstructure analysis results and electrical performance test data obtained for the IGZO thin film samples, the comprehensive quality index QI of the IGZO thin film samples is calculated;

[0009] According to the above comprehensive quality index QI, the production process of IGZO film is optimized by the control variable method to improve the overall performance of IGZO film.

[0010] According to one embodiment of the present invention, the step of preparing an IGZO thin film sample using a pretreated silicon substrate comprises:

[0011] The IGZO film was deposited on the pretreated silicon substrate using a magnetron sputtering device. The sputtering conditions were set as follows: the working gas was a mixed gas of argon and oxygen, wherein the ratio of argon to oxygen was 10:1, the sputtering power was 100 W, the substrate temperature was 200 °C, and the sputtering time was 1 hour.

[0012] According to one embodiment of the present invention, the step of pre-treating the silicon substrate includes:

[0013] The silicon substrate is first cleaned by ultrasonic cleaning and then sterilized by ultraviolet light to ensure that the substrate surface is clean and free of contamination.

[0014] According to an embodiment of the present invention, after the IGZO thin film sample is prepared, it is necessary to cool the IGZO thin film sample to room temperature in a nitrogen environment.

[0015] According to one embodiment of the present invention, the step of performing microstructure analysis on the optical image of the IGZO thin film sample comprises:

[0016] Perform image preprocessing on the optical image of the IGZO thin film sample;

[0017] Perform image segmentation on the pre-processed optical image to separate the IGZO film area from the image background;

[0018] The characteristic parameters within the IGZO film area are extracted, and the structural uniformity index SUI of the IGZO film sample is calculated.

[0019] According to one embodiment of the present invention, the step of performing image preprocessing on the optical image of the IGZO thin film sample comprises:

[0020] Grayscale conversion, converting a color optical image into a grayscale image;

[0021] Contrast enhancement, using histogram equalization method to enhance the contrast of grayscale images and make the film structure clearer;

[0022] Background removal,median filtering is used to remove background noise from grayscale images.

[0023] According to one embodiment of the present invention, the step of performing image segmentation on the preprocessed optical image comprises:

[0024] In the first step, the Otsu threshold segmentation algorithm is used to segment the optical image of the IGZO thin film sample;

[0025] In the second step, morphological operations are used to optimize the segmentation results of the above images.

[0026] According to one embodiment of the present invention, the calculation formula of the structural uniformity index SUI of the IGZO thin film sample is as follows:

[0027]

[0028] Where: n is the number of samples; x i is the attribute value of the i-th sample point; μ is the average attribute value of all sample points; σ is the standard deviation of the attribute value of the sample points.

[0029] According to one embodiment of the present invention, the calculation formula of the comprehensive quality index QI of the IGZO thin film sample is as follows:

[0030]

[0031] Where: m is the number of parameters; w j is the weight of the jth parameter, satisfying P j is the actual measured value of the jth parameter.

[0032] To achieve the above objectives, a second aspect of the present invention provides an electronic device, comprising a memory, a processor and a computer program stored in the memory, wherein when the computer program is executed by the processor, the above IGZO thin film quality evaluation method is implemented.

[0033] Beneficial effects of the present invention:

[0034] The IGZO film quality assessment method and electronic device of the embodiment of the present invention realizes a comprehensive and integrated assessment of the microstructure and electrical properties of the IGZO film by combining optical microscope image analysis with multi-parameter electrical performance testing. This method not only simplifies the process of IGZO film quality assessment and improves the comprehensiveness and accuracy of the assessment, but also provides strong data support for optimizing the preparation process and improving film performance, and has significant industrial application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 1 is a flow chart of a method for evaluating the quality of an IGZO thin film according to an embodiment of the present invention;

[0036] Figure 2 It is a schematic structural diagram of an electronic device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0037] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0038] The IGZO thin film quality evaluation method and electronic device according to embodiments of the present invention will be described below with reference to the accompanying drawings.

[0039] Figure 1 FIG. 4 is a flow chart of a method for evaluating the quality of an IGZO thin film according to an embodiment of the present invention.

[0040] like Figure 1 As shown, the IGZO film quality assessment method includes:

[0041] S1. Pre-treat the silicon substrate, and use the pre-treated silicon substrate to prepare an IGZO thin film sample.

[0042] As an example, a magnetron sputtering device is used to deposit an IGZO film on a pretreated silicon substrate, and the sputtering conditions are set as follows: the working gas is a mixed gas consisting of argon and oxygen, wherein the ratio of argon to oxygen is 10:1, the sputtering power is 100 W, the substrate temperature is 200°C, and the sputtering time is 1 hour.

[0043] In this embodiment, the magnetron sputtering equipment used may be ATC2200 produced by AJA International Inc.

[0044] S2. Use an optical microscope to image the IGZO film samples and perform microstructural analysis on the image content to evaluate the structural quality and uniformity of the IGZO film.

[0045] As an example, the steps for performing microstructure analysis on an optical image of an IGZO thin film sample include:

[0046] S21, performing image preprocessing on the optical image of the IGZO thin film sample;

[0047] S22, performing image segmentation on the pre-processed optical image to separate the IGZO film area from the image background;

[0048] S23. Extract characteristic parameters within the IGZO thin film area and calculate the structural uniformity index SUI of the IGZO thin film sample.

[0049] S3. Conduct comprehensive electrical performance tests on IGZO thin film samples, including using a four-point probe method to measure the resistivity of the thin film samples, a capacitance-voltage test system to measure the dielectric constant and dielectric loss of the thin film samples, and a Hall effect measurement system to determine the carrier concentration and mobility of the thin film samples.

[0050] It should be noted that during the entire test process, it is important to ensure that the test probe has good contact with the IGZO film without obvious contact resistance influence. This can be achieved by regularly checking the contact resistance, using high-quality probes and appropriate contact pressure.

[0051] S4. Based on the above microstructure analysis results and electrical performance test data obtained for the IGZO thin film samples, the comprehensive quality index QI of the IGZO thin film samples is calculated.

[0052] It should be noted that the comprehensive quality index QI is calculated using the weighted average method, which can take into account the influence of different parameters and thus provide a more comprehensive and representative quality evaluation.

[0053] S5. According to the above comprehensive quality index QI, the overall quality of the IGZO film is evaluated, and a basis is provided for optimizing the process parameters for preparing the IGZO film, such as adjusting the sputtering power, working gas ratio, substrate temperature, etc., to improve the film performance.

[0054] The IGZO film quality assessment method of the embodiment of the present invention provides a comprehensive and accurate assessment means for the preparation process optimization and quality control of the IGZO film by combining optical microscope image analysis with multi-parameter electrical performance testing.

[0055] In some embodiments of the present invention, the step of pre-treating the silicon substrate includes:

[0056] First, the silicon substrate is ultrasonically cleaned using a mixture of acetone, isopropanol and deionized water as the cleaning solution. Each ultrasonic cleaning lasts for 10 minutes, followed by ultraviolet light disinfection to ensure that the substrate surface is clean and free of contamination.

[0057] It should be noted that after the IGZO thin film sample is prepared, it needs to be cooled to room temperature in a nitrogen environment to avoid oxidation.

[0058] In some embodiments of the present invention, the optical image of the IGZO thin film sample is preprocessed using ImageJ software, and the specific steps include:

[0059] S211, grayscale conversion, converting the color optical image into a grayscale image for subsequent processing;

[0060] S212, contrast enhancement, using the histogram equalization method to enhance the contrast of the grayscale image to make the film structure clearer;

[0061] S213, background removal, using a median filter with a kernel size of 3×3 pixels to remove background noise in the grayscale image.

[0062] In some embodiments of the present invention, image segmentation is performed on the pre-processed optical image, in order to separate the IGZO film area from the background. The specific steps include:

[0063] S221, using the Otsu threshold segmentation algorithm to segment the optical image of the IGZO thin film sample, effectively separating the IGZO thin film area from the background, and ensuring segmentation accuracy;

[0064] S222. Optimize the segmentation result of the above image by using morphological operation to ensure the integrity and edge clarity of the IGZO thin film area.

[0065] It is worth mentioning that the morphological operation here can be an opening operation and a closing operation, and the kernel size is 3×3 pixels.

[0066] In some embodiments of the present invention, the extracted characteristic parameters of the IGZO thin film region include area, shape factor, grayscale mean and standard deviation, etc. These characteristic parameters are used for quality assessment of the IGZO thin film structure.

[0067] In some embodiments of the present invention, the calculation formula of the structural uniformity index SUI of the IGZO thin film sample is as follows:

[0068]

[0069] Where: n is the number of samples; x i is the attribute value of the i-th sample point; μ is the average attribute value of all sample points; σ is the standard deviation of the attribute value of the sample points.

[0070] The above formula evaluates the uniformity of the overall structure by calculating the absolute value of the standardized deviation of each sample point from the mean value and then averaging it. When the structure is uniform, the SUI value is close to zero; when the structure is non-uniform, the SUI value will be larger. This index provides a quantitative indicator for evaluating the uniformity of the structure or internal properties of the IGZO film.

[0071] In some embodiments of the present invention, in step S3, a resistivity tester model J-Systms J-200 is used to measure the resistivity of the film sample according to the four-point probe method to evaluate the conductive properties of the film;

[0072] Keithley 4200-SCS was used as a capacitance-voltage test system to measure the dielectric constant and dielectric loss of IGZO thin film samples and evaluate the dielectric properties of the film. The test frequency was set to 1 MHz.

[0073] Ecopia HMS-3000 was used as a Hall effect measurement system to measure the carrier concentration and mobility of IGZO thin film samples and evaluate the carrier transport performance of the film. The test temperature was set to room temperature 25°C.

[0074] In some embodiments of the present invention, in step S4, a comprehensive scoring system is used to comprehensively judge the quality of the IGZO film, wherein the comprehensive scoring system includes but is not limited to parameters such as structural uniformity index SUI, resistivity, dielectric constant, dielectric loss, carrier concentration, mobility, etc., and each parameter is set with different weights according to its influence on the film performance. Among them, the calculation formula of the comprehensive quality index QI calculated by the weighted average method for the IGZO film sample is as follows:

[0075]

[0076] Where: m is the number of parameters; w j is the weight of the jth parameter, satisfying P j is the actual measured value of the jth parameter.

[0077] In the above formula, the actual measured value P of each parameter j are multiplied by their corresponding weight w j , and then add up the products of all weighted parameters to get the comprehensive quality index QI. The weight distribution depends on the relative importance of each parameter to the overall quality. In this way, the weighted average method can take into account the influence of different parameters, thereby providing a more comprehensive and representative quality evaluation.

[0078] Through the calculation of the comprehensive quality index QI, specific guidance is provided for optimizing the IGZO thin film preparation process, which significantly improves the film performance and preparation efficiency, and has obvious advantages compared with the method that only relies on a single performance test.

[0079] As an example 1, an IGZO thin film sample was prepared, and a comprehensive quality assessment was performed using the above detailed method. The calculated comprehensive quality index QI was 0.85, indicating that the overall quality of the IGZO thin film was good.

[0080] As an example 2 (control experiment), with other experimental conditions being the same, the sputtering power was adjusted to 150 W, and the above analysis process was repeated. The comprehensive quality index QI was calculated to be 0.78. Compared with example 1, the film quality was slightly reduced, indicating that the sputtering power had a significant impact on the overall quality of the IGZO film.

[0081] As an example three: the sputtering power is further adjusted to 200W, and the above analysis is repeated. The comprehensive quality index QI is calculated to be 0.92. Compared with example one, the film quality is significantly improved, and the film preparation process is optimized.

[0082] Analyze the experimental data and results of the above examples:

[0083] Under laboratory conditions, the IGZO film quality evaluation method of the present invention was used to conduct comprehensive quality judgment on IGZO film samples prepared under 10 different process parameters. The calculated comprehensive quality index QI ranged from 0.65 to 0.95, with a standard deviation of 0.08, indicating that this method can comprehensively and accurately evaluate the quality of IGZO films.

[0084] Corresponding to the above method, the present invention also provides an electronic device.

[0085] like Figure 2 The figure shows a schematic diagram of the structure of an electronic device according to an embodiment of the present invention, wherein the electronic device 200 includes: a processor 201 and a memory 203. The processor 201 and the memory 203 are connected, such as through a bus 202. Optionally, the electronic device 200 may further include a transceiver 204. It should be noted that in actual applications, the transceiver 204 is not limited to one, and the structure of the electronic device 200 does not constitute a limitation on the embodiment of the present invention.

[0086] The processor 201 may be a CPU (Central Processing Unit), a general-purpose processor, a DSP (Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array) or other programmable logic devices, transistor logic devices, hardware components or any combination thereof. It may implement or execute various exemplary logic blocks, modules and circuits described in conjunction with the disclosure of the present invention. The processor 201 may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of a DSP and a microprocessor, etc.

[0087] The bus 202 may include a path to transmit information between the above components. The bus 202 may be a PCI (Peripheral Component Interconnect) bus or an EISA (Extended Industry Standard Architecture) bus. The bus 202 may be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 2 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0088] The memory 203 is used to store a computer program corresponding to the IGZO film quality evaluation method of the above embodiment of the present invention, and the computer program is controlled and executed by the processor 201. The processor 201 is used to execute the computer program stored in the memory 203 to implement the content shown in the above method embodiment.

[0089] The electronic device 200 includes, but is not limited to, mobile terminals such as laptop computers, PADs (tablet computers), and fixed terminals such as desktop computers. Figure 2 The electronic device 200 shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present invention.

[0090] The electronic device 200 of the embodiment of the present invention realizes a comprehensive evaluation of the microstructure and electrical properties of the IGZO film by combining optical microscope image analysis with multi-parameter electrical performance testing. This method not only simplifies the process of IGZO film quality evaluation and improves the comprehensiveness and accuracy of the evaluation, but also provides strong data support for optimizing the preparation process and improving the film performance, and has significant industrial application value.

[0091] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection portion with one or more wirings (electronic device), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or otherwise processing in a suitable manner if necessary, and then stored in a computer memory.

[0092] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0093] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0094] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0095] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A method for evaluating the quality of an IGZO thin film, characterized in that: The method comprises: Pre-treating a silicon substrate, and using the pre-treated silicon substrate to prepare an IGZO thin film sample; The IGZO film samples were imaged using an optical microscope and the image content was analyzed for microstructure to evaluate the structural quality and uniformity of the IGZO film. Conduct comprehensive electrical performance tests on IGZO thin film samples, including using a four-point probe method to measure the resistivity of the thin film samples, a capacitance-voltage test system to measure the dielectric constant and dielectric loss of the thin film samples, and a Hall effect measurement system to determine the carrier concentration and mobility of the thin film samples; Combined with the above microstructure analysis results and electrical performance test data obtained for the IGZO thin film samples, the comprehensive quality index QI of the IGZO thin film samples is calculated; According to the above comprehensive quality index QI, the production process of IGZO film is optimized by the control variable method to improve the overall performance of IGZO film.

2. The IGZO film quality assessment method according to claim 1, characterized in that: The step of preparing the IGZO thin film sample using the pretreated silicon substrate comprises: The IGZO film was deposited on the pretreated silicon substrate using a magnetron sputtering device. The sputtering conditions were set as follows: the working gas was a mixed gas of argon and oxygen, wherein the ratio of argon to oxygen was 10:1, the sputtering power was 100 W, the substrate temperature was 200 °C, and the sputtering time was 1 hour.

3. The IGZO film quality assessment method according to claim 1, characterized in that: The step of pre-treating the silicon substrate comprises: The silicon substrate is first cleaned by ultrasonic cleaning and then sterilized by ultraviolet light to ensure that the substrate surface is clean and free of contamination.

4. The IGZO film quality assessment method according to claim 1, characterized in that: After the IGZO thin film sample is prepared, it is necessary to cool the IGZO thin film sample to room temperature in a nitrogen environment.

5. The IGZO film quality assessment method according to claim 1, characterized in that: The step of performing microstructure analysis on the optical image of the IGZO thin film sample comprises: Perform image preprocessing on the optical image of the IGZO thin film sample; Perform image segmentation on the pre-processed optical image to separate the IGZO film area from the image background; The characteristic parameters within the IGZO film area are extracted, and the structural uniformity index SUI of the IGZO film sample is calculated.

6. The IGZO thin film quality assessment method according to claim 5, characterized in that: The step of performing image preprocessing on the optical image of the IGZO thin film sample comprises: Grayscale conversion, converting a color optical image into a grayscale image; Contrast enhancement, using histogram equalization method to enhance the contrast of grayscale images; Background removal,median filtering is used to remove background noise from grayscale images.

7. The IGZO thin film quality assessment method according to claim 5, characterized in that: The step of performing image segmentation on the preprocessed optical image comprises: In the first step, the Otsu threshold segmentation algorithm is used to segment the optical image of the IGZO thin film sample; In the second step, morphological operations are used to optimize the segmentation results of the above images.

8. The IGZO thin film quality assessment method according to claim 5, characterized in that: The calculation formula of the structural uniformity index SUI of the IGZO thin film sample is as follows: Where: n is the number of samples; x i is the attribute value of the i-th sample point; μ is the average attribute value of all sample points; σ is the standard deviation of the attribute value of the sample points.

9. The IGZO thin film quality assessment method according to claim 1, characterized in that: The calculation formula of the comprehensive quality index QI of the IGZO thin film sample is as follows: Where: m is the number of parameters; w j is the weight of the jth parameter, satisfying P j is the actual measured value of the jth parameter.

10. An electronic device, characterized in that: The method comprises a memory, a processor and a computer program stored in the memory, wherein when the computer program is executed by the processor, the IGZO film quality evaluation method according to any one of claims 1 to 9 is implemented.

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