A flexible near-infrared type artificial retina device and a method of manufacturing the same

Abstract

The application discloses a flexible near-infrared artificial retina device and a preparation method thereof. The flexible near-infrared artificial retina device comprises a flexible substrate, a bottom electrode formed on the flexible substrate, a functional layer comprising an organic ferroelectric polymer film, a rare earth up-conversion nanomaterial and an organic ferroelectric polymer film laminated structure formed on the bottom electrode, and a top transparent electrode formed on the functional layer. The device is excited by near-infrared light, the near-infrared light signal is converted into a reproducible visible light signal by using the anti-Stokes luminescence capability of the rare earth up-conversion nanomaterial, the collection and signal reproduction functions of the near-infrared waveband light information are completed, the processing and memory of the near-infrared information are realized by using the continuously adjustable non-volatile resistance state, and finally the simulation of the artificial retina function is realized.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, specifically to a flexible near-infrared artificial retina device and its fabrication method. Background Technology

[0002] The human visual system plays a crucial role in acquiring information from the external environment. It can quickly perceive optical signals and convert them into electrical signals for further processing, exhibiting advantages such as high efficiency and low power consumption. The retina is a core component of the visual system, playing a key role in recognizing and memorizing optical information. Constructing artificial retinas using electronic devices is of great significance for developing high-performance bionic visual systems.

[0003] Near-infrared light covers the wavelength range of 780nm to 2526nm and is rich in important information about substances, making it useful for qualitative or quantitative analysis of their composition. However, the human eye can only observe optical information in the visible light band (400nm to 780nm) and has almost no response to the infrared band. This means that infrared information can only be obtained through auxiliary electronic devices, limiting the functionality of the human eye. Therefore, developing a bionic retina with near-infrared band response has great application potential to solve this problem.

[0004] Organic polymer ferroelectric materials can undergo stable ferroelectric phase transitions under voltage stimulation, thereby enabling signal memory modulation and simulating visual memory functions. However, organic polymer ferroelectric materials are difficult to respond to light excitation in the near-infrared band, limiting their application in the construction of biomimetic retinas in the near-infrared band.

[0005] Traditional integrated circuit devices are based on rigid silicon substrates, which suffer from problems such as difficulty in bending, fragility, and limited application scenarios. Flexible electronic devices, on the other hand, have rapidly developed due to their advantages such as wearability, bendability, stretchability, light weight, portability, and impact resistance, offering significant advantages over silicon-based devices in specific applications. Given the three-dimensional spherical structure and curved surface of the human eye, the fabrication of flexible artificial retina devices is crucial for their practical application. Summary of the Invention

[0006] This invention discloses a flexible near-infrared artificial retina device, comprising: a flexible substrate; a bottom electrode formed on the flexible substrate; a functional layer comprising an organic ferroelectric polymer film / rare earth upconversion nanomaterial / organic ferroelectric polymer film stacked structure formed on the bottom electrode; and a top transparent electrode formed on the functional layer. The device is excited by near-infrared light, and the anti-Stokes emission capability of the rare earth upconversion nanomaterial is used to convert the near-infrared light signal into a reproducible visible light signal, thereby completing the function of acquiring and reproducing near-infrared light information. At the same time, the continuously adjustable non-volatile resistance state is used to process and memorize near-infrared information, ultimately realizing the simulation of the function of an artificial retina.

[0007] In the flexible near-infrared artificial retina device of the present invention, preferably, the organic ferroelectric polymer film is P(VDF-TrFE).

[0008] In the flexible near-infrared artificial retina device of the present invention, preferably, the rare earth upconversion nanomaterial is NaYF4:Yb 3+ Er 3+ .

[0009] In the flexible near-infrared artificial retina device of the present invention, preferably, the top transparent electrode is ITO, FTO, ZTO, or AZO.

[0010] In the flexible near-infrared artificial retina device of the present invention, preferably, the flexible substrate is flexible glass, PET, PEN, PI, or PDMS.

[0011] This invention also discloses a method for fabricating a flexible near-infrared artificial retina device, comprising the following steps: forming a bottom electrode on a flexible substrate; forming an organic ferroelectric polymer film / rare earth upconversion nanomaterial / organic ferroelectric polymer film stacked structure on the bottom electrode as a functional layer; forming a top transparent electrode on the functional layer, exciting the device with near-infrared light, utilizing the anti-Stokes emission capability of the rare earth upconversion nanomaterial to convert the near-infrared light signal into a reproducible visible light signal, completing the function of acquiring and reproducing near-infrared light information, and simultaneously utilizing the continuously adjustable non-volatile resistance state to realize the processing and memory of near-infrared information, ultimately realizing the simulation of artificial retina function.

[0012] In the method for fabricating the flexible near-infrared artificial retina device of the present invention, preferably, the organic ferroelectric polymer film is P(VDF-TrFE).

[0013] In the method for fabricating the flexible near-infrared artificial retina device of the present invention, preferably, the rare earth upconversion nanomaterial is NaYF4:Yb 3+ Er 3+ .

[0014] In the method for preparing the flexible near-infrared artificial retina device of the present invention, preferably, P(VDF-TrFE) organic ferroelectric polymer is coated by spin coating, and after being fully coated, it is spin coated for 30s to 120s using a spin coater at a speed of 1000 rpm to 3000 rpm.

[0015] Subsequently, P(VDF-TrFE) organic ferroelectric polymer films were obtained by annealing in a tube furnace under a nitrogen atmosphere at a temperature of 60℃~150℃ for 1 hour~6 hours.

[0016] In the method for fabricating the flexible near-infrared artificial retina device of the present invention, preferably, NaYF4:Yb is spin-coated onto an organic ferroelectric polymer film. 3+ Er 3+ Rare earth upconversion nanomaterials were spin-coated at speeds of 1000 rpm to 3000 rpm for 30 to 120 seconds.

[0017] Then, bake in a tube oven under a nitrogen atmosphere at a temperature of 60°C to 150°C for 10 to 60 minutes.

[0018] Beneficial effects:

[0019] (1) Use electronic devices to construct an artificial retina to realize the core functions of signal acquisition, processing and memory. Use bionics to achieve high efficiency and low power consumption similar to biological vision systems and improve the information processing capabilities of electronic devices.

[0020] (2) Breaking the limitations of the visible light response band of the traditional visual system, the near-infrared band is introduced as the excitation source, enabling the device to achieve functional transcendence on the basis of imitating the artificial retina, and obtain richer optical information acquisition functions, making the bionic retina more advantageous in processing light signals.

[0021] (3) Organic polymer ferroelectric materials are used as the core functional materials to obtain the memory and processing functions of artificial retina devices, and the anti-Stokes luminescence capability of rare earth upconversion nanomaterials is used to obtain the sensing capability of near-infrared light information, thus integrating sensing, storage, and computing functions in the same device. The material system of the device has excellent flexibility, laying the foundation for the application of wearable bionic devices. Attached Figure Description

[0022] Figure 1 This is a flowchart of the fabrication method for a flexible near-infrared artificial retina device.

[0023] Figures 2-6 This is a schematic diagram of the structure of each stage in the fabrication process of a flexible near-infrared artificial retina device.

[0024] Figure 7 This is a schematic diagram of the operation of a flexible near-infrared artificial retina device. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions in the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only for explaining this invention and are not intended to limit this invention. The described embodiments are merely some embodiments of this invention, not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0026] In the description of this invention, it should be noted that the terms "upper," "lower," "vertical," and "horizontal," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0027] Furthermore, many specific details of the invention, such as the structure, materials, dimensions, processing techniques, and methods of the device, are described below to provide a clearer understanding of the invention. However, as those skilled in the art will understand, the invention may be implemented without adhering to these specific details. Unless specifically indicated below, various parts of the device may be made of materials known to those skilled in the art, or may employ materials with similar functionality developed in the future.

[0028] Figure 1 This is a flowchart of a method for fabricating a flexible near-infrared artificial retina device. (For example...) Figure 1 As shown, the fabrication method of the flexible near-infrared artificial retina device includes the following steps:

[0029] Step S1: Prepare a flexible glass substrate 100 for fabricating a flexible near-infrared artificial retina device. The flexible substrate can also be PET, PEN, PI, PDMS, etc.

[0030] Step S2: A bottom electrode Al layer 101 with a thickness of 30 nm to 100 nm is prepared on the flexible substrate 100 using photolithography and physical vapor deposition, such as... Figure 2 As shown. The material of the bottom electrode can also be Pt, Au, Pd, Al, etc.

[0031] Step S3: A P(VDF-TrFE) organic ferroelectric polymer is prepared on the bottom electrode 101 using spin coating. After covering the substrate, it is spin-coated at 2000 rpm for 60 seconds using a spin coater. Subsequently, it is annealed in a tube furnace under a nitrogen atmosphere at 100°C for 3 hours to obtain the organic ferroelectric polymer film 102. Figure 3 As shown. However, the present invention is not limited thereto. The rotation speed can be in the range of 1000 rpm to 3000 rpm, etc.; the spin coating time can be in the range of 30s to 120s; the annealing temperature can be in the range of 60℃ to 150℃; and the annealing time can be in the range of 1 hour to 6 hours.

[0032] Step S4: Spin-coating NaYF4:Yb onto the organic ferroelectric polymer film 102 3+ Er 3+ Rare earth upconversion nanomaterial 103 is used to modify organic ferroelectric polymer film 102, such as... Figure 4 As shown. The spin coating speed is 2000 rpm, and the spin coating time is 60 s. Subsequently, it is baked in a tube furnace at 100°C for 30 minutes under a nitrogen atmosphere. However, this invention is not limited to this; the spin coating speed can be selected from 1000 rpm to 3000 rpm, etc.; the spin coating time can be selected from 30 s to 120 s; the baking temperature can be selected from 60°C to 150°C; and the annealing time can be selected from 10 minutes to 60 minutes.

[0033] Step S5: P(VDF-TrFE) ferroelectric polymer is prepared on the above structure using spin coating. After covering the substrate, it is spin-coated at 2000 rpm for 60 seconds using a spin coater. Subsequently, it is annealed in a tube furnace under a nitrogen atmosphere at 100°C for 3 hours to obtain the organic ferroelectric polymer film 104. Figure 5 As shown. However, the present invention is not limited thereto. The spin coating speed can be selected from 1000 rpm to 3000 rpm, etc.; the spin coating time can be selected from 30s to 120s; the baking temperature can be selected from 60℃ to 150℃; and the annealing time can be selected from 10 minutes to 60 minutes.

[0034] Step S6: A top transparent electrode ITO105 with a thickness of 20nm to 50nm is fabricated using photolithography and physical vapor deposition to complete the device fabrication. Figure 6 As shown. Electrode materials can also be FTO, ZTO, AZO, etc.

[0035] like Figure 6As shown, the flexible near-infrared artificial retina device includes: a flexible substrate 100; a bottom electrode 101 formed on the flexible substrate 100; a functional layer comprising a stacked structure of organic ferroelectric polymer film 102, rare earth upconversion nanomaterial 103, and organic ferroelectric polymer film 104 formed on the bottom electrode 101; and a top transparent electrode 105 formed on the functional layer.

[0036] like Figure 7 As shown, the device is excited using 980nm near-infrared light. The anti-Stokes luminescence capability of rare-earth upconversion nanomaterials is utilized to convert the near-infrared light signal into a reproducible visible light signal, thus completing the acquisition and signal reproduction functions of near-infrared light information. Simultaneously, continuously adjustable non-volatile resistance states are used to process and memorize near-infrared information, ultimately simulating the function of an artificial retina.

[0037] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A flexible near-infrared artificial retina device, characterized in that, include: Flexible substrate; The bottom electrode is formed on the flexible substrate; A functional layer comprising an organic ferroelectric polymer film\rare earth upconversion nanomaterial\organic ferroelectric polymer film stacked structure is formed on the bottom electrode; A top transparent electrode is formed on the functional layer. The device is excited by near-infrared light, and the anti-Stokes luminescence capability of rare-earth upconversion nanomaterials is used to convert the near-infrared light signal into a reproducible visible light signal, thus completing the function of acquiring and reproducing near-infrared light information. At the same time, the processing and memory of near-infrared information are realized by using continuously adjustable non-volatile resistance states, ultimately achieving the simulation of artificial retina function.

2. The flexible near-infrared artificial retina device according to claim 1, characterized in that, The organic ferroelectric polymer film is P(VDF-TrFE).

3. The flexible near-infrared artificial retina device according to claim 1, characterized in that, The rare earth upconversion nanomaterial is NaYF4:Yb 3+ Er 3+ .

4. The flexible near-infrared artificial retina device according to claim 1, characterized in that, The top transparent electrode is ITO, FTO, ZTO or AZO.

5. The flexible near-infrared artificial retina device according to claim 1, characterized in that, The flexible substrate is flexible glass, PET, PEN, PI, or PDMS.

6. A method for fabricating a flexible near-infrared artificial retina device, characterized in that, Includes the following steps: A bottom electrode is formed on a flexible substrate; An organic ferroelectric polymer film / rare earth upconversion nanomaterial / organic ferroelectric polymer film stacked structure is formed on the bottom electrode as a functional layer. A top transparent electrode is formed on the functional layer. The device is excited by near-infrared light, and the anti-Stokes luminescence capability of rare-earth upconversion nanomaterials is used to convert the near-infrared light signal into a reproducible visible light signal, thus completing the function of acquiring and reproducing near-infrared light information. At the same time, the processing and memory of near-infrared information are realized by using continuously adjustable non-volatile resistance states, ultimately achieving the simulation of artificial retina function.

7. The method for fabricating a flexible near-infrared artificial retina device according to claim 6, characterized in that, The organic ferroelectric polymer film is P(VDF-TrFE).

8. The method for fabricating a flexible near-infrared artificial retina device according to claim 6, characterized in that, The rare earth upconversion nanomaterial is NaYF4:Yb 3+ Er 3+ .

9. The method for fabricating a flexible near-infrared artificial retina device according to claim 7, characterized in that, P(VDF-TrFE) organic ferroelectric polymer was coated by spin coating. After the coating was fully spread, it was spin coated for 30s to 120s at a speed of 1000 rpm to 3000 rpm using a spin coater. Subsequently, P(VDF-TrFE) organic ferroelectric polymer films were obtained by annealing in a tube furnace under a nitrogen atmosphere at a temperature of 60℃~150℃ for 1 hour~6 hours.

10. The method for fabricating a flexible near-infrared artificial retina device according to claim 8, characterized in that, NaYF4:Yb is spin-coated onto an organic ferroelectric polymer film. 3+ Er 3+ Rare earth upconversion nanomaterials were spin-coated at speeds of 1000 rpm to 3000 rpm for 30 s to 120 s. Then, bake in a tube oven under a nitrogen atmosphere at a temperature of 60°C to 150°C for 10 to 60 minutes.

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