CN118251117A - Flexible brain-like chip and preparation method thereof - Google Patents
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Abstract
The invention discloses a flexible brain-like chip and a preparation method thereof. The flexible brain-like chip comprises a flexible substrate, a bottom electrode layer, a memristor structure layer and a top electrode layer, wherein the flexible substrate, the bottom electrode layer, the memristor structure layer and the top electrode layer are arranged in a laminated mode, the memristor structure layer comprises a first epitaxial layer, a light-emitting layer and a second epitaxial layer which are arranged in a laminated mode, the first epitaxial layer is located on the bottom electrode layer, the top electrode layer is located on the second epitaxial layer, the light-emitting layer is made of indium gallium nitride, one of the first epitaxial layer and the second epitaxial layer is made of an n-type doped semiconductor material, and the other of the first epitaxial layer and the second epitaxial layer is made of a p-type doped semiconductor material. In the flexible brain-like chip, the memristor structure layer is formed by two epitaxial layers and one luminescent layer, so that the memristor function can be realized by sensing external signals, the light source stimulation function can also be realized by emitting light under voltage, and the composite function of the flexible brain-like chip is realized.
Description
Technical Field
The invention belongs to the technical field of brain-like chips, and particularly relates to a flexible brain-like chip and a preparation method thereof.
Background
With the rapid development of the information age, traditional perception systems/chips face bottlenecks in information processing capacity and energy efficiency, and the moore's law and von neumann architecture in traditional theory are gradually unable to meet the demands of storage operations. The brain-like chip is a novel chip capable of simulating a brain processing information mechanism, has the advantages of memory calculation fusion, high parallelism, high energy efficiency, high density integration and the like, is an important candidate device for simulating a brain neural network and breaks through the traditional computer von neumann architecture. On the other hand, wearable devices and the like are rapidly changing aspects of human life, and flexible electronic technologies related to the aspects of light weight, flexibility, reliability and biocompatibility of related equipment or devices are also increasingly important. Therefore, the development of flexible brain-like chips is an important and urgent task in current "brain-like science" research.
For the brain, neurons are the fundamental unit of the nervous system, a cell made up of dendrites, cell bodies, axons and synapses. Inside the neuron, the signal is transmitted in a bioelectric potential one-way, and in the signal transmission process, the synapse completes the conversion of electricity and transmitter and plays a great role, so the synapse is the best incision point of the simulated brain nervous system.
The current synapse flexible brain-like device is usually made of functional materials with memristive properties, and has a single function although the function of simulating synapses can be achieved.
Disclosure of Invention
The invention solves the technical problems that: how to provide a flexible brain-like chip with memristive and luminous composite functions.
The application discloses a flexible brain-like chip, which comprises a flexible substrate, a bottom electrode layer, a memristor structure layer and a top electrode layer which are arranged in a laminated manner, wherein the memristor structure layer comprises a first epitaxial layer, a light-emitting layer and a second epitaxial layer which are arranged in a laminated manner, the first epitaxial layer is positioned on the bottom electrode layer, the top electrode layer is positioned on the second epitaxial layer, the light-emitting layer is made of indium gallium nitride, one of the first epitaxial layer and the second epitaxial layer is made of an n-type doped semiconductor material, and the other of the first epitaxial layer and the second epitaxial layer is made of a p-type doped semiconductor material.
Preferably, the flexible brain-like chip further comprises an insulating layer, and the insulating layer surrounds and covers the side face of the memristive structure layer.
Preferably, the light emitting layer includes a plurality of light emitting unit layers arranged at intervals, the second epitaxial layer includes a plurality of second epitaxial unit layers arranged at intervals, the top electrode layer includes a plurality of top electrode unit layers arranged at intervals, and a plurality of light emitting unit layers, a plurality of second epitaxial unit layers and a plurality of top electrode unit layers are arranged in a one-to-one correspondence and laminated manner.
Preferably, the plurality of light emitting unit layers, the plurality of second epitaxial unit layers and the plurality of top electrode unit layers are respectively distributed in an array.
Preferably, the sides of the light emitting unit layer and the second epitaxial unit layer are both covered with an insulating layer.
Preferably, the first epitaxial layer, the light emitting layer and the second epitaxial layer are of a thin film structure or a nano-pillar structure.
The application also discloses a preparation method of the flexible brain-like chip, which comprises the following steps:
sequentially preparing a sacrificial layer and a memristive structure layer which are arranged in a laminated manner on an epitaxial substrate;
Stripping the memristive structure layer from the epitaxial substrate and transferring the memristive structure layer to a bottom electrode layer, wherein the bottom electrode layer is prepared on a flexible substrate in advance;
And preparing a top electrode layer on the memristive structure layer.
Preferably, the preparation method further comprises:
And preparing an insulating layer on the side surface of the memristor structure layer.
The preparation method further comprises the following steps:
etching the top electrode layer and the memristive structure layer to divide the top electrode layer into a plurality of top electrode unit layers at intervals, divide the second epitaxial layer into a plurality of second epitaxial unit layers at intervals, and divide the light-emitting layer into a plurality of light-emitting unit layers at intervals.
Preferably, before preparing the top electrode layer, the preparation method further comprises: etching the memristive structure layer to divide the second epitaxial layer into a plurality of second epitaxial unit layers arranged at intervals and a plurality of light-emitting unit layers arranged at intervals;
the method for preparing the top electrode layer on the memristive structure layer comprises the following steps: and preparing a top electrode unit layer on each second epitaxial unit layer.
Preferably, the method of stripping the memristive structure layer from the substrate and transferring to the bottom electrode layer comprises:
Preparing an etching electrode on the side surface of the epitaxial substrate or the surface deviating from the sacrificial layer, conducting the etching electrode and the sacrificial layer, and covering the etching electrode with a protective layer;
Placing the sacrificial layer in an electrochemical solution, and performing electrochemical etching to remove the sacrificial layer;
and stripping the memristive structure layer from the epitaxial substrate and transferring the memristive structure layer to a bottom electrode layer.
The flexible brain-like chip and the preparation method thereof disclosed by the invention have the following technical effects compared with the prior art:
In the flexible brain-like chip, the memristor structure layer is formed by two epitaxial layers and one luminescent layer, so that the memristor function can be realized by sensing external signals, the light source stimulation function can also be realized by emitting light under voltage, and the composite function of the flexible brain-like chip is realized.
Drawings
FIG. 1 is a schematic cross-sectional view of a flexible brain-like chip according to a first embodiment of the present invention;
FIG. 2 is a top view of a flexible brain-like chip according to a first embodiment of the invention;
FIG. 3 is a flow chart of a method of fabricating a flexible brain-like chip according to a second embodiment of the present invention;
FIG. 4 is a schematic diagram of a sacrificial layer and a memristive structure layer fabricated in accordance with a second embodiment of the present disclosure;
FIG. 5 is a graph of the photoelectric response of a flexible brain-like chip provided in example four of embodiment two of the present invention to a transient pulse signal;
FIG. 6 is a graph of the photoelectric response of a flexible brain-like chip to a sustain pulse signal provided in example four of embodiment two of the present invention;
Fig. 7 is a light-emitting physical diagram of a flexible brain-like chip according to example five in a second embodiment of the present invention.
Detailed Description
The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
Before describing various embodiments of the present application in detail, the technical idea of the present application will be briefly described first: the brain-like chip in the prior art can be formed by adopting a material with memristive property, but has single function and is usually only used for simulating synapses. Therefore, the application provides a flexible brain-like chip, which comprises a memristive structural layer formed by two epitaxial layers and a middle luminescent layer, and electrodes are arranged on two sides of the memristive structural layer, on one hand, when the memristive structural layer senses an external optical signal or biological signal, the memristive structural layer can be converted into an electric signal and is transmitted out through the electrodes, the memristive function is realized, when the voltage is applied to the memristive structural layer through the electrodes, the memristive structural layer can emit light, and light source stimulation is provided for biological cells, so that the composite function of the flexible brain-like chip is realized.
Specifically, as shown in fig. 1, the flexible brain-like chip includes a flexible substrate 10, a bottom electrode layer 20, a memristive structural layer 30 and a top electrode layer 40 that are stacked, where the memristive structural layer 30 includes a first epitaxial layer 31, a light-emitting layer 32 and a second epitaxial layer 33 that are stacked, the first epitaxial layer 31 is located on the bottom electrode layer 20, the top electrode 40 is located on the second epitaxial layer 33, the material of the light-emitting layer 32 is indium gallium nitride, one of the first epitaxial layer 31 and the second epitaxial layer 33 is an n-type doped semiconductor material, and the other is a p-type doped semiconductor material. In use, the flexible brain-like chip connects the bottom electrode layer 20 and the top electrode layer 40 to an external circuit by way of wire bonds via leads 80.
The material of the first epitaxial layer 31 may be In 1-n-xAlnGax N, gallium oxide or indium gallium zinc oxide, x is more than or equal to 0 and less than or equal to 1, N is more than or equal to 0 and less than or equal to 1, n+x is more than or equal to 0 and less than or equal to 1, and N-type doping or p-type doping is performed. The material of the second epitaxial layer 33 may be In 1-z-hAlhGaz N material, where z is greater than 0 and less than or equal to 1, h is greater than or equal to 0 and less than or equal to 1, and z+h is greater than or equal to 0 and less than or equal to 1, and N-type doping or p-type doping is performed. The luminescent layer can be made of In 1-mGam N material, m is more than 0 and less than or equal to 1. Wherein the content of In 1-n-xAlnGax N or gallium oxide or indium gallium zinc oxide material and In 1-mGamN、In1-z-hAlhGaz N material is uniformly distributed, gradually increased or gradually decreased. Illustratively, the first epitaxial layer 31, the light emitting layer 32, and the second epitaxial layer 33 may each have a single-layer or multi-layer structure with an n-type or p-type doping concentration of 1×10 18-1×1024cm-3. The first epitaxial layer 31 has a thickness ranging from 200nm to 4000nm, the light emitting layer 32 has a thickness ranging from 30nm to 600nm, and the second epitaxial layer 33 has a thickness ranging from 20nm to 900nm.
Further, the flexible brain-like chip of the first embodiment further includes an insulating layer 50, where the insulating layer 50 surrounds and covers the side surface of the memristive structural layer 30, so that an insulating effect can be achieved, and short circuit of the side surface of the memristive structural layer 30 is avoided. The material of the insulating layer 50 may be silicon dioxide.
As shown in fig. 2, in another embodiment, the light emitting layer 32 includes a plurality of light emitting cell layers (not shown) arranged at intervals, the second epitaxial layer 33 includes a plurality of second epitaxial cell layers 33a arranged at intervals, and the top electrode layer 40 includes a plurality of top electrode cell layers 40a arranged at intervals, the plurality of light emitting cell layers, the plurality of second epitaxial cell layers 33a, and the plurality of top electrode cell layers 40a being stacked one on top of another. Illustratively, the plurality of light emitting cell layers, the plurality of second epitaxial cell layers 33a, and the plurality of top electrode cell layers 40a are respectively distributed in an array to form a plurality of memristive cell layers distributed in an array, and each memristive cell layer shares the first epitaxial layer 31.
Further, the side surfaces of the light emitting cell layer and the second epitaxial cell layer 33a are each provided with an insulating layer 50, which can prevent the occurrence of short circuits of the respective memristive cell layers.
The flexible brain-like chip disclosed by the embodiment is characterized in that the memristor structure layer is formed by two epitaxial layers and one luminescent layer, so that the memristor function can be realized by sensing external signals, the light source stimulation function can also be realized by emitting light under voltage, and the composite function of the flexible brain-like chip is realized.
Further, as shown in fig. 3, the second embodiment also discloses a preparation method of the flexible brain-like chip, which comprises the following steps:
Step S10: sequentially preparing a sacrificial layer 70 and a memristive structure layer 30 which are arranged in a stacked manner on an epitaxial substrate 60;
step S20: stripping the memristive structural layer 30 from the epitaxial substrate 60 and transferring to the bottom electrode layer 20, wherein the bottom electrode layer 20 is prepared on the flexible substrate 10 in advance;
Step S30: a top electrode layer 40 is fabricated on the memristive structural layer 30.
Further, before step S30 is performed, the preparation method further includes forming an insulating layer 50 on the side surface of the memristive structure layer 30, so as to avoid short-circuiting of the side surface of the memristive structure layer 30.
Further, after step S30, the method further includes etching the top electrode layer 40 and the memristive structure layer to divide the top electrode layer 40 into a plurality of top electrode unit layers 40a at intervals, divide the second epitaxial layer 33 into a plurality of second epitaxial unit layers 33a at intervals, and divide the light emitting layer 32 into a plurality of light emitting unit layers at intervals, thereby forming a plurality of memristive unit layers. Further, an insulating layer 50 may be formed on the side surfaces of each of the second epitaxial cell layers 33a and the light emitting cell layers to avoid a short circuit between each of the memristive cell layers.
In another embodiment, before step S30 is performed, the memristive structure layer 30 may be etched first to divide the second epitaxial layer 33 into a plurality of second epitaxial unit layers 33a disposed at intervals and divide the light emitting layer 32 into a plurality of light emitting unit layers disposed at intervals, and then a top electrode unit layer is formed on each of the second epitaxial unit layers 33a to form the top electrode layer 40.
Further, step S20 includes the steps of: preparing an etching electrode on the side surface of the epitaxial substrate 60 or the surface facing away from the sacrificial layer 70, conducting the etching electrode with the sacrificial layer 70, and covering the etching electrode with a protective layer; placing the sacrificial layer in an electrochemical solution, and performing electrochemical etching to remove the sacrificial layer; the memristive structural layer 30 is peeled off from the epitaxial substrate 60 and transferred to the bottom electrode layer 20.
Illustratively, the epitaxial substrate 60 may employ any one or a combination of two or more of a silicon wafer, a sapphire substrate, a GaN self-supporting substrate, a silicon carbide substrate, a diamond substrate, a metal substrate, and a substrate covered with a two-dimensional thin film material. The sacrificial layer 70 comprises a single layer or a plurality of Al 1-bGab N layers, wherein b is more than or equal to 0 and less than 1, and b values corresponding to two adjacent layers are different. The bottom electrode layer 20 may be any one of a conductive film, a two-dimensional thin film material, and an epoxy resin having indium tin oxide or silver nanowires formed on the surface thereof, a conductive tape, and a conductive silver paste, and the flexible substrate 10 may be a poly (naphthol) substrate (PEN) or a polyethylene terephthalate (PET).
The flexible brain-like chip prepared by the second embodiment has memristive and luminous characteristics, and can emit blue light when voltages are applied to two ends of the bottom electrode layer and the top electrode layer, for example, 5V; when a bias voltage, such as-2V, is directly applied to the two electrode layers, the chip has a neural-like synaptic property, or memristive property, to the detected light source or power supply.
The following describes the detailed procedure of the method for manufacturing the flexible brain-like chip in the second embodiment by different examples.
Example one
As shown in fig. 4, the epitaxial substrate 60 in step S10 is a silicon substrate, and is epitaxially grown in a growth chamber of a Metal Organic Chemical Vapor Deposition (MOCVD) equipment, specifically as follows:
First, growing an AlGaN layer with a thickness of about 2500nm on the front surface of the epitaxial substrate 60 to obtain a sacrificial layer 70;
secondly, growing a Si doped GaN epitaxial layer with the thickness of 2000nm on the sacrificial layer 70, wherein the doping concentration is 1 multiplied by 10 23cm-3, so as to obtain a first epitaxial layer 31;
Thirdly, growing an InGaN epitaxial layer on the GaN epitaxial layer, wherein the InGaN epitaxial layer is of a multi-layer structure, specifically, the thickness of In 0.2Ga0.8N/GaN,In0.2Ga0.8 N/GaN grown for 10 times alternately is 3nm/12nm, and the light-emitting layer 32 is obtained;
And fourthly, growing an Al 0.05Ga0.95 N epitaxial layer with the thickness of 10nm on the InGaN epitaxial layer, and growing a Mg-doped GaN epitaxial layer with the thickness of 100nm, wherein the doping concentration is 2 multiplied by 10 21cm-3, so as to obtain a second epitaxial layer 33, and finally forming the memristor structural layer 30.
Wherein, in the In 1-n-xAlnGax N material of the sacrificial layer 70 In the first step, x is 1, and N is 0; in 1-mGam N material of the light-emitting layer 32 In the third step has m value of 0.8, and In component In the actual sample fluctuates and is unevenly distributed; in 1-z-hAlhGaz N material of the second epitaxial layer 33 In the fourth step is a two-layer structure, z of the layer close to In 1-mGam N is 0.95, h is 0.05, z of the other layer is 1, and h is 0.
In step 20, preparing an etching electrode on the back surface of the epitaxial substrate 60 by using an In ball, and covering the etching electrode by using epoxy resin to ensure that the etching electrode is not conducted with the electrochemical solution; then, electrochemical etching is performed in NaOH solution at a voltage of about 3V to completely or partially etch off the AlGaN sacrificial layer, and after peeling off the epitaxial substrate 60, the memristive structural layer 30 over the sacrificial layer 70 is obtained, and the memristive structural layer 30 is transferred to a flexible polynaphthol ester substrate (flexible substrate 10) having one side covered with an indium tin oxide layer (bottom electrode layer 20), wherein the GaN epitaxial layer is disposed on the indium tin oxide layer.
Further, a 100nm SiO 2 layer is formed on the GaN epitaxial layer (second epitaxial layer 33) as an insulating layer 50 to insulate the side walls of the memristive structural layer 30 and prevent shorting.
In step S30, the top electrode layer 40 is prepared by photolithography, and the top electrode layer 40 is made of Ni/Au with a thickness of 30nm/40 nm. The bottom electrode layer 20, the top electrode layer 40 and the external circuit are connected by means of photolithography or bonding wires through the wires 80.
Example two
Step S10 and step S20 of the second example are the same as those of the first example, except that: after the memristive structural layer 30 on the stripped sacrificial layer is transferred onto the flexible polynaphthol ester substrate (flexible substrate 10) covered with the indium tin oxide layer (bottom electrode layer 20) in step S20, a plurality of elongated grooves are processed on the memristive structural layer 30 through a first photolithography process, so that the memristive structural layer 30 is cut to form a plurality of memristive unit layers, and an array is formed. The etching depth of the grooves extends to the first epitaxial layer 31, namely the GaN epitaxial layer 11, but the memristive structural layer 30 is not etched through, and only the second epitaxial layer 33 is divided into a plurality of second epitaxial unit layers 33a arranged at intervals and the light-emitting layer 32 is divided into a plurality of light-emitting unit layers arranged at intervals, and the memristive unit layers are conducted through the first epitaxial layer 31. Then, a plurality of top electrode unit layers 40a are formed on the second epitaxial unit layer 33a by a second photolithography process.
Further, a second photoetching process is adopted to prepare a SiO 2 layer with the thickness of 30nm around each memristor unit layer, and the SiO 2 layer is used as an insulating layer 50 to prevent short circuit; each memristive unit layer is prepared into an independent top electrode unit layer 40a through a photoetching process to form a top electrode layer 40, and the bottom electrode layer 20 is directly used as a common electrode and is shared by all chip arrays.
Example three
The epitaxial substrate 60 in step S10 is a sapphire substrate, and is epitaxially grown in a growth chamber of a Metal Organic Chemical Vapor Deposition (MOCVD) apparatus, specifically as follows:
Firstly, growing a Si doped GaN sacrificial layer with the thickness of about 3000nm on the front surface of a sapphire substrate, wherein the doping concentration is 5 multiplied by 10 24cm-3, so as to obtain a sacrificial layer 70;
Secondly, growing a Si doped GaN epitaxial layer with the thickness of 2500nm on the GaN sacrificial layer, wherein the doping concentration is 1 multiplied by 10 23cm-3, and obtaining a first epitaxial layer 31;
Thirdly, growing an InGaN epitaxial layer on the GaN epitaxial layer, wherein the InGaN epitaxial layer is of a multi-layer structure, specifically, the thickness of In 0.3Ga0.7N/GaN,In0.3Ga0.7 N/GaN grown for 15 times alternately is 2nm/10nm, and the light-emitting layer 32 is obtained;
And fourthly, growing an Al 0.1Ga0.9 N epitaxial layer with the thickness of 15nm on the InGaN epitaxial layer, and growing a Mg-doped GaN epitaxial layer with the thickness of 150nm, wherein the doping concentration is 5 multiplied by 10 21cm-3, so as to obtain a second epitaxial layer 33, and finally forming the memristor structural layer 30.
Wherein, in the In 1-n-xAlnGax N material of the sacrificial layer 70 In the first step, x is 1, and N is 0; in 1-mGam N material of the light-emitting layer 32 In the third step has m value of 0.7, and In component In the actual sample fluctuates and is unevenly distributed; in 1-z-hAlhGaz N material of the second epitaxial layer 33 In the fourth step is a two-layer structure, z of the layer close to In 1-mGam N is 0.9, h is 0.1, z of the other layer is 1, and h is 0.
In step S20, a layer of SiO 2 with a thickness of 80nm/90nm is formed on the GaN epitaxial layer to insulate the sidewall of the memristor structural layer 30 and prevent short circuit, and the top electrode layer 40 is prepared by using a photolithography process, where the top electrode layer 40 is Ti/Au with a thickness of 80nm/90 nm.
In step S30, preparing an etching electrode on the side surface of the sapphire substrate by using an In ball, and covering the etching electrode by using epoxy resin to ensure that the etching electrode is not conducted with the electrochemical solution; and the top electrode layer 40 is covered with photoresist to prevent corrosion by electrochemical solution, then electrochemical etching is performed in KOH solution at a voltage of about 5V, the GaN sacrificial layer is partially etched away, the memristive structural layer 30 on the sacrificial layer is stripped off, and the memristive structural layer 30 is transferred onto flexible PEN (flexible substrate 10) with one side covered with a conductive silver paste layer (bottom electrode layer 20), wherein the GaN epitaxial layer is disposed on the conductive silver paste layer. Finally, the bottom electrode layer 20, the top electrode layer 40 and the external circuit are connected by means of photolithography or bonding wires through the wires 80.
Example four
The epitaxial substrate 60 in step S10 is a silicon substrate, and is epitaxially grown in a growth chamber of a molecular beam epitaxy apparatus (MBE), specifically as follows:
firstly, growing an AlN sacrificial layer with the thickness of about 3nm on the front surface of a silicon substrate to obtain a sacrificial layer 70;
second, growing a Si doped GaN nano-pillar epitaxial layer with the thickness of 300nm on the sacrificial layer 70 to obtain a first epitaxial layer 31;
Thirdly, growing an In 0.05Ga0.95 N nano-pillar epitaxial layer with the thickness of 100nm on the GaN epitaxial layer to obtain a light-emitting layer 32;
fourthly, growing a Mg-doped GaN nano-pillar epitaxial layer with the thickness of 30nm on the In 0.05Ga0.95 N epitaxial layer to obtain a second epitaxial layer 33, and finally forming a memristor structural layer 30;
That is, in 1-n-xAlnGax N material of the sacrificial layer 70 In the first step, x has a value of 0 and N is 1; in 1-mGam N material of the light-emitting layer 32 In the third step has m value of 0.95, and In component In the actual sample fluctuates and is unevenly distributed; the z value In the In 1-z-hAlhGaz N material of the second epitaxial layer 33 is 1, and h is 0;
in step S20, a layer of graphene is transferred on top of the nano-pillar, and a plurality of elongated grooves are processed on the memristive structural layer 30 through a first photolithography process to divide the memristive structural layer 30 into memristive cell layers to form an array, and the second epitaxial layer 33 is divided into a plurality of second epitaxial cell layers 33a arranged at intervals and the light-emitting layer 32 is divided into a plurality of light-emitting cell layers arranged at intervals; a 300nm SiO 2 layer was prepared on the sidewall of the memristive cell layer, serving as the insulating layer 50.
Next, the top electrode layer 40 is prepared by a second photolithography process, and the remaining steps are the same as those in example three, and will not be described here.
The brain-like chip related to the present embodiment has a nerve-like synaptic property, and when irradiated by a light source, the chip has a memory function for the detected photon signal, as shown in fig. 5; when the stimulus of the signal source is continuously applied, the chip can continuously respond, and when the signal source is stopped, the chip responds and slowly returns to the initial state, as shown in fig. 6.
Example five
The procedure of the preparation method of example five is basically the same as that of example one, except that: sacrificial layer 70 is a plurality of layers, first an AlN sacrificial layer and then an AlGaN layer, adjacent to epitaxial substrate 60. The brain-like chip related to the present embodiment has a light emitting function, and when a voltage of 5V is applied, the chip emits blue light, which can be used as a light source, as shown in fig. 7.
While certain embodiments have been shown and described, it would be appreciated by those skilled in the art that changes and modifications may be made without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.
Claims (11)
1. The flexible brain-like chip is characterized by comprising a flexible substrate, a bottom electrode layer, a memristor structure layer and a top electrode layer which are arranged in a laminated mode, wherein the memristor structure layer comprises a first epitaxial layer, a light-emitting layer and a second epitaxial layer which are arranged in a laminated mode, the first epitaxial layer is located on the bottom electrode layer, the top electrode layer is located on the second epitaxial layer, the light-emitting layer is made of indium gallium nitride, one of the first epitaxial layer and the second epitaxial layer is made of an n-type doped semiconductor material, and the other of the first epitaxial layer and the second epitaxial layer is made of a p-type doped semiconductor material.
2. The flexible brain-like chip of claim 1, further comprising an insulating layer surrounding the sides of the memristive structural layer.
3. The flexible brain-like chip of claim 2, wherein the light-emitting layer comprises a plurality of light-emitting cell layers arranged at intervals, the second epitaxial layer comprises a plurality of second epitaxial cell layers arranged at intervals, the top electrode layer comprises a plurality of top electrode cell layers arranged at intervals, and the plurality of light-emitting cell layers, the plurality of second epitaxial cell layers and the plurality of top electrode cell layers are stacked in a one-to-one correspondence.
4. The flexible brain-like chip of claim 3, wherein the plurality of light-emitting cell layers, the plurality of second epitaxial cell layers, and the plurality of top electrode cell layers are each distributed in an array.
5. The flexible brain-like chip of claim 3, wherein the sides of the light-emitting cell layer and the second epitaxial cell layer are each covered with an insulating layer.
6. The flexible brain-like chip of claim 1, wherein the first epitaxial layer, the light-emitting layer, and the second epitaxial layer are thin film structures or nano-pillar structures.
7. A method of manufacturing a flexible brain-like chip according to any one of claims 1 to 6, comprising:
sequentially preparing a sacrificial layer and a memristive structure layer which are arranged in a laminated manner on an epitaxial substrate;
Stripping the memristive structure layer from the epitaxial substrate and transferring the memristive structure layer to a bottom electrode layer, wherein the bottom electrode layer is prepared on a flexible substrate in advance;
And preparing a top electrode layer on the memristive structure layer.
8. The method of manufacturing according to claim 7, further comprising:
And preparing an insulating layer on the side surface of the memristor structure layer.
9. The method of manufacturing according to claim 7, further comprising:
etching the top electrode layer and the memristive structure layer to divide the top electrode layer into a plurality of top electrode unit layers at intervals, divide the second epitaxial layer into a plurality of second epitaxial unit layers at intervals, and divide the light-emitting layer into a plurality of light-emitting unit layers at intervals.
10. The method of manufacturing according to claim 7, wherein before manufacturing the top electrode layer, the method of manufacturing further comprises: etching the memristive structure layer to divide the second epitaxial layer into a plurality of second epitaxial unit layers arranged at intervals and a plurality of light-emitting unit layers arranged at intervals;
the method for preparing the top electrode layer on the memristive structure layer comprises the following steps: and preparing a top electrode unit layer on each second epitaxial unit layer.
11. The method of preparing as claimed in claim 9, wherein the method of stripping the memristive structure layer from the substrate and transferring onto the bottom electrode layer comprises:
Preparing an etching electrode on the side surface of the epitaxial substrate or the surface deviating from the sacrificial layer, conducting the etching electrode and the sacrificial layer, and covering the etching electrode with a protective layer;
Placing the sacrificial layer in an electrochemical solution, and performing electrochemical etching to remove the sacrificial layer;
and stripping the memristive structure layer from the epitaxial substrate and transferring the memristive structure layer to a bottom electrode layer.
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