A method for preparing and testing a zinc oxide photoelectric synaptic device
By preparing zinc oxide photoelectric synaptic devices on ITO glass substrates, using photolithography, wet etching and magnetron sputtering processes, the problems of complex and inaccurate testing methods of traditional device preparation are solved, and device preparation and testing methods with excellent performance, low cost and flexible adaptability are achieved.
Patent Information
- Application Number
- CN202411887799.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-20
- Publication Date
- 2025-04-04
AI Technical Summary
The preparation process of traditional photoelectric synaptic devices is complex, has high cost, and is fixed in shape and size, making it difficult to meet the needs of different application scenarios, and the testing method cannot accurately evaluate the performance of the device under different lighting conditions.
ITO glass substrate is used to prepare zinc oxide photoelectric synaptic devices through processes such as photolithography, wet etching and magnetron sputtering, and the current-voltage characteristics of the device are tested by adjusting the ultraviolet light irradiation intensity and precision source meter to achieve flexible and controllable preparation and testing of the device.
It reduces production costs, improves device consistency and reliability, provides flexible application adaptability and performance optimization support, and promotes the development of neuromorphic computing.
Smart Images
Figure CN119767844A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the field of semiconductor technology, and in particular relates to a preparation and testing method of a zinc oxide photoelectric synapse device. Background Art
[0002] Neuromorphic computing is a new computing model inspired by the human brain and is considered an important development direction for artificial intelligence computing in the future. However, the huge computing power required to realize neuromorphic computing is accompanied by high energy consumption, and the traditional von Neumann processor architecture is difficult to meet this demand. Therefore, developing new computing architectures to achieve efficient and low-power neuromorphic computing has become a research hotspot.
[0003] The characteristics of human brain neuron information activities include massive parallelism, distributed storage, self-learning, and low power consumption. These advantages are mainly attributed to biological synapses in the nervous system that contain computing and storage capabilities. Inspired by this, the design and implementation of artificial synapses have become the key to achieving neuromorphic computing. Optoelectronic synaptic devices have become an important part of neuromorphic computing because of their ability to intelligently process optoelectronic input signals.
[0004] Traditional optoelectronic synaptic devices are subject to many limitations in their applications. First, their preparation process is relatively complex and requires high-precision equipment and technical support, resulting in high production costs. Secondly, traditional devices have fixed shapes and sizes, lack flexibility and adjustability, and are difficult to meet the needs of different application scenarios. In addition, in terms of testing methods, traditional testing methods are often unable to accurately evaluate the performance of devices under different lighting conditions, thereby limiting the optimization and improvement of devices. In recent years, zinc oxide has become a preferred material for the preparation of optoelectronic synaptic devices due to its excellent semiconductor properties. However, the preparation and testing methods of zinc oxide optoelectronic synaptic devices still need to be further optimized and improved.
[0005] Therefore, the research and development of zinc oxide photoelectric synaptic devices with excellent performance and simple preparation and their testing methods are of great significance for promoting the development of neuromorphic computing. The present invention aims to provide a preparation and testing method of zinc oxide photoelectric synaptic devices based on ITO glass substrate to solve the above problems. Summary of the invention
[0006] Based on the above problems existing in the prior art, the present invention provides a preparation and testing method of a zinc oxide photoelectric synapse device based on an ITO glass substrate, which overcomes the limitations of traditional preparation methods and provides a flexible and controllable new approach for the application of zinc oxide devices in optoelectronic electronic devices.
[0007] The technical solution of the present invention is as follows: A method for preparing a zinc oxide photoelectric synapse device comprises the following steps: a. Cleaning the ITO glass substrate; b. Use a photolithography machine to transfer the customized mask pattern to the ITO glass substrate; c. Wet etching ITO using a hydrochloric acid etching solution and a water bath heating pot to form an interdigitated ITO electrode; d. Sputtering a zinc oxide film on the photolithographic ITO glass substrate using a magnetron sputtering device to form a zinc oxide photoelectric synapse layer; e. Remove the tape covering the electrode and use silver paste and copper wire to connect the reserved parts of the interdigital electrodes; f. Use kapton tape to stick the device on a fixed base to complete the preparation of the zinc oxide photoelectric synapse device.
[0008] In step b, the photolithography process includes fixing the ITO glass sheet on the rotating table of the coating machine, adding positive resist, rotating the coating at a speed of 1500 rpm and 3000 rpm, and then performing ultraviolet light exposure, development, drying and cooling.
[0009] In step c, the conditions for wet etching of ITO are etching in an etching solution heated to 85° C. for 40 minutes, followed by cleaning with acetone, anhydrous ethanol and ultrapure water in sequence, and drying with nitrogen.
[0010] In step d, the conditions for magnetron sputtering deposition of the zinc oxide film are as follows: a sputtering power of 120 W, 10 sccm of Ar as a reaction gas, and a sputtering time of 15 minutes.
[0011] A method for testing a zinc oxide photoelectric synapse device comprises the following steps: a. Place the handheld UV lamp on two lifting platforms; b. By adjusting the height of the lifting platform, the zinc oxide photoelectric synapse device to be tested can receive ultraviolet light of different intensities; c. Use a UV power meter to test the UV intensity received by the device; d. Test the device at a fixed voltage according to the different UV light intensity values set in the experiment, and observe and record the electrical characteristics and performance of the device.
[0012] During the test, a precision source meter was used to test the current-voltage characteristics of the device under different UV light intensities. The voltage scanning range was -5V to 5V, and the light and dark cycle tests were performed alternately every 30s.
[0013] The photoelectric synapse characteristics of the device were evaluated by testing the short-period It response characteristics of the device under different UV light intensities, where the photocurrent refers to the current of the device under different light intensities minus the current in the dark field.
[0014] The preparation and testing methods of the zinc oxide photoelectric synapse device provided by the present invention show significant beneficial effects compared with the traditional preparation and testing methods of the photoelectric synapse device.
[0015] In terms of preparation methods, the present invention uses ITO glass substrates and uses processes such as photolithography, wet etching, and magnetron sputtering to achieve simple and efficient preparation of zinc oxide photoelectric synaptic devices. This method not only reduces production costs, but also improves the consistency and reliability of the device, making it possible for large-scale production and application of the device.
[0016] In terms of the testing method, the present invention adjusts the height of the lifting platform so that the device can receive UV light of different intensities, and uses a precision source meter to test the current-voltage characteristics of the device under different UV light intensities. This testing method can accurately evaluate the performance of the device and provide strong support for the optimization and improvement of the device.
[0017] In addition, the zinc oxide photoelectric synaptic device prepared by the present invention has adjustable current-voltage characteristics, which is suitable for applications in the fields of photoelectric sensing, photoelectric modulation and photoelectric response. This characteristic enables the device to be flexibly adjusted according to different application scenarios and requirements, thereby meeting the needs of different fields.
[0018] In summary, the preparation and testing methods of the zinc oxide photoelectric synaptic device provided by the present invention have significant beneficial effects, which not only reduce the production cost and improve the consistency and reliability of the device, but also provide strong support for the optimization and improvement of the device, and promote the development of neuromorphic computing. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Figure 1 It is a device structure of a zinc oxide photoelectric synapse device based on an ITO glass substrate.
[0020] Figure 2 This is the preparation process of zinc oxide photoelectric synapse devices based on ITO glass substrate.
[0021] Figure 3 It is a testing method for zinc oxide photoelectric synaptic devices based on ITO glass substrate.
[0022] Figure 4 These are the test results of the synaptic characteristics of zinc oxide photoelectric synaptic devices based on ITO glass substrate under ultraviolet light intensity. DETAILED DESCRIPTION
[0023] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to be able to fully convey the scope of the present disclosure to those skilled in the art. It should be noted that, in the absence of conflict, the embodiments of the present invention and the features described in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.
[0024] The present invention provides a method for preparing and testing a zinc oxide photoelectric synaptic device based on an ITO glass substrate, and the specific steps are as follows: (1) Cleaning ITO glass substrate (2) Use photolithography equipment to transfer the customized mask pattern to the ITO glass substrate (3) Wet etching of ITO using hydrochloric acid etching solution and water bath heating pot (4) Finally, a magnetron sputtering device is used to sputter a zinc oxide film on the photolithographic ITO glass substrate. (5) Remove the tape covering the electrode, use silver paste and scrape the copper wires at both ends to lead the interdigital electrodes to the reserved areas. (6) Use kapton tape to stick the device to a fixed base. (7) First, place the handheld UV lamp on two lifting platforms, and then adjust the height of the lifting platforms so that the equipment can receive UV light of different intensities.
[0025] (8) Use a precision source meter to test the current-voltage characteristics of the device under different UV light intensity values Example
[0026] The device structure and preparation process of the embodiment are as follows Figure 1 and Figure 2 As shown, the basic device structure is a metal-semiconductor-metal structure, with n-type ZnO as the semiconductor: (1) Preparation and testing methods of zinc oxide photoelectric synaptic devices based on ITO glass substrate: (a) Place the cut ITO glass in a beaker, add an appropriate amount of acetone, and clean it in a 100W ultrasonic cleaner for 5 minutes; pour out the acetone, pour in an appropriate amount of anhydrous ethanol, and clean it in a 100W ultrasonic cleaner for 5 minutes; pour out the anhydrous ethanol, pour in an appropriate amount of ultrapure water, and clean it in a 100W ultrasonic cleaner for 5 minutes; use high-purity nitrogen to blow dry the substrate for later use (b) Fix the ITO glass sheet on the rotating table of the photoresist machine, use a dropper to drop the positive photoresist on the four corners of the ITO glass sheet, first manually rotate the photoresist roughly to ensure that the photoresist covers the front side, then place it in the photoresist machine and rotate it at 1500 rpm for 15 seconds, and then rotate it at 3000 rpm for 30 seconds; Place the ITO glass substrate after the spin coating on a baking plate and dry it for 60 seconds; adjust the finger pattern part of the mask to the center of the sample, with the side with the photoresist facing the ultraviolet light source, and expose it to ultraviolet light for 60 seconds; place the exposed sample on a baking plate for drying, and time it for 60 seconds to catalyze the photochemical reaction in the photoresist, and then place the sample at room temperature for cooling; use tweezers to clamp the substrate in a beaker filled with 0.4% NaOH solution and shake it for about 60 seconds for development. After taking it out, immediately rinse the residual developer with ultrapure water, blow it dry with nitrogen, check the pattern and set it aside; the developed sample is placed on a baking plate for drying to remove excess solution in the photoresist and increase adhesion to the substrate; then cool the sample at room temperature.
[0027] (c) Place the ITO substrate with patterned photoresist in an etching solution heated to 85°C. After etching for 40 minutes, take out the sample and place it in a beaker. Slowly pour in an appropriate amount of acetone, and then remove the glue in an ultrasonic cleaner set to 100W for 5 minutes. Then use anhydrous ethanol and ultrapure water in a 100W ultrasonic cleaner for 5 minutes; take out the sample, rinse it and blow it dry with nitrogen, observe whether the electrode pattern is complete, use a multimeter to test whether the electrode end is conductive and whether the non-electrode part is insulated. After the test is correct, put it in an oven for drying.
[0028] (d) Magnetron sputtering was used to deposit zinc oxide thin films on ITO / glass substrates. The sputtering power was 120 W, 10 sccm of Ar was used as the reaction gas, and the sputtering time was 15 min. (e) The device is then attached to a fixed base using kapton tape. The handheld UV lamp is first placed on two lifting platforms. The height of the lifting platforms is then adjusted so that the device can receive UV light of different intensities.
[0029] (f) Then the output characteristics of the device under different purple light intensities were tested using a source meter. The voltage sweep range was -5V-5V, and the light and dark cycles were alternating every 30s. In addition, Figure 4 The photocurrent represented in refers to the current of the device under different light intensities minus the current under dark field, and the different light intensities are shown in the legend.
[0030] It can be seen that the photoresponse current of the device increases with the increase of ultraviolet light intensity. This is because under the same bias voltage and irradiation time interval, the stronger the ultraviolet light intensity, the more electron-hole pairs will be generated in the zinc oxide semiconductor, the more carriers there are, and the current increases. By testing the short-period It response characteristics of the device under different ultraviolet light irradiation powers, it can be seen that the current peak of the device continues to increase, which is consistent with the synaptic characteristics of organisms.
[0031] The present invention provides a preparation and testing method for a zinc oxide photoelectric synaptic device based on an ITO glass substrate. In terms of the preparation method, the preparation of the zinc oxide photoelectric synaptic device is achieved by performing photolithography and chemical etching to transfer patterns on an ITO glass substrate, and depositing a zinc oxide film on the prepared interdigitated ITO electrode substrate. In terms of the testing method, the height of the lifting platform is adjusted so that the device can receive ultraviolet light of different intensities. During the test, the device to be tested is placed under an ultraviolet light source, and an ultraviolet power meter is used to test the ultraviolet light intensity received by the device. Different ultraviolet light intensity values are set according to the experiment, the device is tested at a fixed voltage, and the performance of the device is evaluated by observing the electrical characteristics and performance.
[0032] The fabrication method of this zinc oxide optoelectronic synaptic device is simple, scalable, and has high fabrication efficiency and device consistency. The testing method can also accurately evaluate the performance of the device and provide a deep understanding of the synaptic characteristics of the device.
[0033] (1) Enhanced device reliability and stability: By using ITO glass substrate to prepare synaptic devices, the durability of the device can be improved, enabling it to withstand certain mechanical stress, thereby enhancing the reliability and stability of the device.
[0034] (2) Provides simplified and scalable preparation process: Compared with the traditional preparation process, the preparation process of ITO glass substrate synaptic devices is simpler, easier to control, and has higher preparation efficiency and device consistency. This makes the preparation process easier to achieve large-scale production and provides feasibility for large-scale applications.
[0035] (3) Optimization of device performance was achieved: zinc oxide nanowires were grown by low-temperature hydrothermal method to change the zinc oxide nanostructure, and the carrier transport characteristics in zinc oxide were improved by annealing process. The IV response characteristics of zinc oxide devices under five process combinations, namely, growing nanowires only, annealing only, growing nanowires followed by annealing, growing nanowires after annealing, and sputtering only, and the It response characteristics under different UV light powers were prepared and tested. The results show that the introduction of annealing process can improve the carrier mobility, interface quality and stability of synaptic devices, thereby improving their synaptic performance.
[0036] (4) Provides an in-depth understanding of synaptic properties: Through performance observation in the test method, the electrical behavior and synaptic properties of the device under different strain conditions can be studied in detail. This provides a basis for understanding synaptic properties and performance optimization, and provides important guidance for further improvement and innovation of synaptic devices. The characteristics displayed by the device are also similar to the learning experience behavior in biological synapses, which can mimic the Pavlovian conditioning theory in biological synapses. After the conditioned training stage, the threshold current can be reached only by unconditioned stimulation. The device array was designed and implemented to realize the memory retrieval function.
[0037] In summary, the present invention provides a method for preparing and testing a zinc oxide optoelectronic synaptic device based on an ITO glass substrate, which overcomes the limitations of conventional preparation methods and provides a flexible and controllable new approach for the application of zinc oxide devices in optoelectronic devices. This invention has broad application prospects and is of great significance in the fields of energy converters and electronic devices.
Claims
1. A method for preparing a zinc oxide photoelectric synapse device, characterized in that: The following steps are involved: a. Clean the ITO glass substrate; b. Use photolithography equipment to transfer the customized mask pattern to the ITO glass substrate; c. Wet-etching ITO using a hydrochloric acid etching solution and a water bath heating pot to form an interdigitated ITO electrode; d. sputtering a zinc oxide film on the photolithographic ITO glass substrate using a magnetron sputtering device to form a zinc oxide photoelectric synapse layer; e. Remove the tape covering the electrode and use silver paste and copper wire to make lead connections to the reserved parts of the interdigital electrodes; f. Use kapton tape to stick the device on a fixed base to complete the preparation of the zinc oxide photoelectric synapse device.
2. The method for preparing the zinc oxide photoelectric synapse device according to claim 1, characterized in that: In step b, the photolithography process includes fixing the ITO glass sheet on the rotating table of the coating machine, adding positive resist, rotating the coating at a speed of 1500 rpm and 3000 rpm, and then performing ultraviolet light exposure, development, drying and cooling.
3. The method for preparing the zinc oxide photoelectric synapse device according to claim 1, characterized in that: In step c, the conditions for wet etching of ITO are etching in an etching solution heated to 85° C. for 40 minutes, followed by cleaning with acetone, anhydrous ethanol and ultrapure water in sequence, and drying with nitrogen.
4. The method for preparing the zinc oxide photoelectric synapse device according to claim 1, characterized in that: In step d, the conditions for magnetron sputtering deposition of the zinc oxide film are as follows: a sputtering power of 120 W, 10 sccm of Ar as a reaction gas, and a sputtering time of 15 minutes.
5. A method for testing a zinc oxide photoelectric synapse device, characterized in that: The following steps are involved: a. Place the handheld UV lamp on two lifting platforms; b. By adjusting the height of the lifting platform, the zinc oxide photoelectric synapse device to be tested can receive ultraviolet light of different intensities; c. Use a UV power meter to test the UV light intensity received by the device; d. Test the device at a fixed voltage according to the different UV light intensity values set in the experiment, and observe and record the electrical characteristics and performance of the device.
6. The method for testing a zinc oxide photoelectric synapse device according to claim 5, characterized in that: During the test, a precision source meter was used to test the current-voltage characteristics of the device under different UV light intensities. The voltage scanning range was -5V to 5V, and the light and dark cycle tests were performed alternately every 30s.
7. The method for testing a zinc oxide photoelectric synapse device according to claim 5 or 6, characterized in that: The photoelectric synapse characteristics of the device were evaluated by testing the short-period It response characteristics of the device under different UV light intensities, where the photocurrent refers to the current of the device under different light intensities minus the current in the dark field.