A color-identifying optical floating gate device, method of manufacture and method of use

Abstract

The application discloses a color recognition light floating grid device, a preparation method and an application method. The light floating grid device comprises a substrate, a channel layer, a light floating grid layer, a first electrode and a second electrode. The channel layer is covered on a preset range of the substrate, and the light floating grid layer is covered on the channel layer. The light floating grid layer is used for absorbing light of different wavelengths. The channel layer is used for modulating carriers in the channel layer under the action of light of different wavelengths. The first electrode and the second electrode are arranged on the substrate, and the channel layer covers the first electrode and the second electrode. The application has the advantages of simple structure, high integration, improved recognition speed, reduced power consumption and wide application in the technical field of image recognition.

Description

Technical Field

[0001] The present invention relates to the field of image recognition technology, and in particular to a color recognition optical floating gate device, a preparation method and an application method. Background Art

[0002] Traditional color recognition solutions typically use a combination of red, green, and blue filters and three different sensors for the corresponding colors to complete the color differentiation task. The filters can selectively transmit light of specific wavelengths, while the sensors correspond to red, green, and blue respectively. The sensors capture the light signals that pass through each filter and perform a weighted combination of the light signals to identify the color of the target. However, this solution has disadvantages such as complex structure and low integration. The need to set up separate filters and sensors for each color makes the construction and maintenance process more complicated. In addition, due to the separation between the color sensing module and the processing module, traditional color recognition systems also have problems such as slow recognition speed and high power consumption. Summary of the Invention

[0003] In order to solve the above problems, the purpose of the present invention is to provide a method for preparing and applying a color-recognizing optical floating gate device, which has a simple structure and high integration, can improve recognition speed and reduce power consumption.

[0004] In one aspect, the present invention provides a color-recognizing optical floating gate device, comprising a substrate, a channel layer, an optical floating gate layer, a first electrode, and a second electrode, wherein the channel layer covers a preset range of the substrate, and the optical floating gate layer covers the channel layer, wherein:

[0005] The optical floating grating layer is used to absorb light of different wavelengths;

[0006] The channel layer is used to modulate carriers inside the channel layer under the action of light of different wavelengths;

[0007] A first electrode and a second electrode are provided on the substrate, and the channel layer covers the first electrode and the second electrode.

[0008] Optionally, the optical floating grating layer is made of a mixture of at least three light absorbing materials, and the at least three light absorbing materials include at least a first light absorbing material, a second light absorbing material and a third light absorbing material.

[0009] The first light absorbing material is used to absorb light in the blue light band;

[0010] The second light absorbing material is used to absorb light in the green wavelength band;

[0011] The third light absorbing material is used to absorb light in the red light band.

[0012] Optionally, the optical floating grating layer has a thickness ranging from 15 nm to 20 nm.

[0013] Optionally, the substrate is made of sapphire and / or quartz.

[0014] Optionally, the substrate is made of polyethylene terephthalate film and / or polyimide film.

[0015] Optionally, the material of the channel layer includes a two-dimensional semiconductor material.

[0016] Optionally, the thickness of the channel layer is in the range of 3-5 nm.

[0017] Optionally, the first electrode is a source electrode, the second electrode is a drain electrode, and materials of the source electrode and the drain electrode both include chromium gold.

[0018] In another aspect, the present invention provides a method for preparing a color-recognizing optical floating gate device, comprising the following steps:

[0019] preparing a first electrode and a second electrode on a substrate;

[0020] A channel layer is formed and disposed within a preset range of the substrate; the channel layer is used to modulate carriers within the channel layer under the action of light of different wavelengths, and the channel layer covers the first electrode and the second electrode;

[0021] Mixing at least three light absorbing materials in a preset ratio to obtain a mixed light absorbing material, wherein each light absorbing material is used to absorb light of a different wavelength;

[0022] The mixed light absorbing material is applied to the surface of the channel layer away from the substrate to obtain an optical floating gate layer.

[0023] In another aspect, the present invention provides an application method of a color recognition optical floating gate device, wherein the color recognition optical floating gate device is applied to extract color features of a color image, comprising the following steps:

[0024] Obtaining a pulse sequence corresponding to the color image according to the color image; the pulse sequence is a light sequence of the color image;

[0025] Inputting the pulse sequence into an optical floating gate device array and detecting the electrical signal sequence generated by the optical floating gate device array; the optical floating gate device array is composed of a plurality of the aforementioned optical floating gate devices;

[0026] The color characteristics of the color image are obtained according to the electrical signal sequence.

[0027] The implementation of the present invention includes the following beneficial effects: the optical floating gate device of the present invention includes a substrate, a channel layer, an optical floating gate layer, a first electrode, and a second electrode, the channel layer covers a preset range of the substrate, and the optical floating gate layer covers the channel layer, wherein the optical floating gate layer is used to absorb light of different wavelengths, and the channel layer is used to modulate carriers inside the channel layer under the action of light of different wavelengths, the first electrode and the second electrode are provided on the substrate, and the channel layer covers the first electrode and the second electrode, when the optical floating gate layer receives light of different colors, the optical floating gate layer can form different numbers of photoelectrons according to the wavelength of the light, and the photoelectrons are injected into the channel layer, causing the carriers in the channel layer to change, forming currents of different sizes, and an external acquisition card can identify the color according to the correspondence between the current and the color, without the need to build a system of multiple filters and acquisition cards, and different colors can be recognized on the same device, with a simple structure and high integration, and can improve the recognition speed and reduce power consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is an overall structural diagram of a color-recognizing optical floating gate device provided by the present invention;

[0029] Figure 2 This is a cross-sectional view along AA of a color recognition optical floating gate device provided by the present invention;

[0030] Figure 3 It is an ultraviolet-visible absorption spectrum of an optical floating gate device provided by the present invention;

[0031] Figure 4 This is a schematic diagram of the response behavior of an optical floating gate device provided by the present invention to light of three characteristic wavelengths;

[0032] Figure 5 This is a flow chart of reservoir calculation for an optical floating gate device provided by the present invention;

[0033] Figure 6 This is a diagram showing the verification results of the reservoir computing capability of an optical floating gate device provided by the present invention. DETAILED DESCRIPTION

[0034] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The step numbers in the following embodiments are provided for ease of description only and do not limit the order of the steps. The order of execution of the steps in the embodiments can be adaptively adjusted based on the understanding of those skilled in the art.

[0035] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments and are not intended to limit the embodiments of the present application. The singular forms "a," "the," and "the" used in the embodiments of the present application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0036] When the following description refers to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. Instead, they are merely examples of devices and methods consistent with certain aspects of the present application, as detailed in the appended claims. For those of ordinary skill in the art, the specific meanings of the above terms in this application will be understood according to specific circumstances.

[0037] like Figure 1 and Figure 2 As shown, Figure 1 This is the overall structure diagram of a color-recognizing optical floating gate device. Figure 2 The present invention provides a color-recognizing optical floating gate device along the AA cross-sectional view.

[0038] The optical floating gate device includes a substrate, a channel layer, an optical floating gate layer, a first electrode and a second electrode, wherein the channel layer covers a preset range of the substrate, and the optical floating gate layer covers the channel layer, wherein:

[0039] The optical floating grating layer is used to absorb light of different wavelengths;

[0040] The channel layer is used to modulate carriers inside the channel layer under the action of light of different wavelengths;

[0041] A first electrode and a second electrode are provided on the substrate, and the channel layer covers the first electrode and the second electrode.

[0042] Specifically, the optical floating gate layer 5 covers the surface of the channel layer 2 away from the substrate 1 and covers the upper surface of the channel layer 2. The optical floating gate layer 5 and the channel layer 2 form a heterojunction. The optical floating gate layer 5 is used to absorb light of different wavelengths and inject photogenerated electrons into the channel layer 2 under the action of light of different wavelengths. The channel layer 2 is used to modulate the carriers inside it under the action of photogenerated electrons or holes, thereby generating different currents.

[0043] The generated current can be connected to an external acquisition card or other measurement device through the first electrode and the second electrode.

[0044] The first electrode may be but is not limited to the source electrode 3 , the second electrode may be but is not limited to the drain electrode 4 , the first electrode and the second electrode are arranged on the substrate 1 , and the channel layer 2 covers the first electrode and the second electrode.

[0045] The first electrode and the second electrode can be, but are not limited to, chromium gold. The thickness of the first electrode ranges from 4 to 6 nm, and the thickness of the second electrode ranges from 45 to 55 nm. In one possible solution, the thickness of the first electrode is 5 nm, and the thickness of the second electrode is 50 nm.

[0046] In some embodiments, the optical floating grating layer is made of a mixture of at least three light absorbing materials, wherein the at least three light absorbing materials include at least a first light absorbing material, a second light absorbing material, and a third light absorbing material.

[0047] The first light absorbing material is used to absorb light in the blue light band;

[0048] The second light absorbing material is used to absorb light in the green wavelength band;

[0049] The third light absorbing material is used to absorb light in the red light band.

[0050] Specifically, the first light absorbing material may be but is not limited to cesium lead chlorine nanosheets (CsPbCl3 nanosheets), the second light absorbing material may be but is not limited to cesium lead bromine nanosheets (CsPbBr3 nanosheets), and the third light absorbing material may be but is not limited to cesium lead iodine nanosheets (CsPbI3 nanosheets).

[0051] The optical floating gate layer can be a hybrid perovskite nanosheet, which is made by mixing at least three types of perovskite nanosheets. Depending on the preset ratio, the hybrid perovskite nanosheet has different absorption capabilities for light in different bands.

[0052] The hybrid perovskite nanosheets can be, but are not limited to, made by uniformly mixing CsPbBr3 nanosheets, CsPbI3 nanosheets and CsPbCl3 nanosheets in a preset ratio. By modulating the concentration and mixing ratio of each perovskite nanosheet, the characteristic absorption wavelength position, that is, the position of the absorption peak, can be adjusted. CsPbCl3 nanosheets, CsPbBr3 nanosheets and CsPbI3 nanosheets have very narrow absorption peaks for blue light with a wavelength of 405nm, green light with a wavelength of 532nm and red light with a wavelength of 635nm, respectively. After physically mixing the three, they can exhibit sensitive and distinguishable absorption characteristics for blue, green and red colors of light.

[0053] For example, CsPbCl3, CsPbBr3, and CsPbI3 nanosheets mixed in a preset ratio of 1:3:6 correspond to characteristic absorption wavelengths of 405nm, 532nm, and 635nm, respectively. If the preset ratios are different, the characteristic absorption wavelengths will shift. In this embodiment, the present invention also provides a mixture of CsPbCl3, CsPbBr3, and CsPbI3 nanosheets in a preset ratio of 1:2:4, which can correspond to characteristic absorption wavelengths of 435nm, 550nm, and 650nm, respectively.

[0054] In some embodiments, the thickness of the optical floating gate layer 5 is in the range of 15-20 nm, and may be 18 nm.

[0055] In some embodiments, the substrate 1 may be a rigid substrate 1 , and the material of the rigid substrate 1 may include one or more of sapphire, quartz, and Si / SiO 2 .

[0056] In some embodiments, the substrate 1 may be a flexible substrate 1 , and the material of the flexible substrate 1 may include one or both of a polyethylene terephthalate film (PET film) and a polyimide film.

[0057] The thickness range of the rigid substrate 1 and the flexible substrate 1 is not limited and can be, but is not limited to, 280-290 nm. In one embodiment, it can be 285 nm. The substrate 1 is used to support the first electrode, the second electrode, and the channel layer 2, and also serves as a backup gate electrode for modulating the carrier state of the channel layer 2.

[0058] In some embodiments, the material of the channel layer 2 includes a two-dimensional semiconductor material, which may be, but is not limited to, molybdenum disulfide, tungsten selenide, molybdenum telluride, black phosphorus, and the like.

[0059] In some embodiments, the thickness of the channel layer 2 is in the range of 3-5 nm. In one possible solution, the thickness of the channel layer 2 is 4 nm.

[0060] In some embodiments, the present invention provides a specific optical floating gate device for recognizing colors, such as Figure 2 As shown, with the substrate at the bottom and the optical floating gate layer at the top, the specific color recognition optical floating gate device includes a substrate 1, a channel layer 2, and an optical floating gate layer 5 from bottom to top. The optical floating gate layer 5 is located on the upper surface of the channel layer 2 and covers the channel layer 2. The substrate 1 is Si / SiO2, the channel layer 2 is molybdenum disulfide, the optical floating gate layer 5 is a hybrid perovskite nanosheet optical floating gate, and one end of the channel layer 2 (on the substrate 1) is covered with a source electrode 3, and the other end is covered with a drain electrode 4.

[0061] The substrate 1 is a standard Si / SiO2 sheet, wherein the SiO2 thickness is 285nm, the channel layer 2 thickness is 4nm, the optical floating gate layer 5 is a mixed CsPbCl3, CsPbBr3, and CsPbI3 nanosheet optical floating gate with a thickness of 18nm, and the source electrode 3 and the drain electrode 4 are both made of chromium gold. The thickness of the source electrode 3 is 5nm, and the thickness of the drain electrode 4 is 50nm.

[0062] In some embodiments, the present invention provides a method for preparing a color-recognizing optical floating gate device, comprising the following steps:

[0063] S110, preparing a first electrode and a second electrode on a substrate.

[0064] Specifically, the outlines of the first electrode and the second electrode are engraved on the substrate by using a laser direct writing technique, and the conductive material is plated onto the outlines of the first electrode and the second electrode by using a thermal evaporation technique.

[0065] S120 , forming a channel layer, and disposing the channel layer on a preset range of the substrate.

[0066] The channel layer is used to modulate carriers inside the channel layer under the action of light of different wavelengths, and the channel layer covers the first electrode and the second electrode.

[0067] Specifically, the channel layer is manufactured by a mechanical peeling and stacking method, and the channel layer is disposed on the substrate by a transfer method.

[0068] S130 , mixing at least three light absorbing materials according to a preset ratio to obtain a mixed light absorbing material.

[0069] Each light absorbing material is used to absorb light of different wavelengths.

[0070] Specifically, the preset ratio is the same as that explained in the previous embodiment. First, CsPbCl3, CsPbBr3, and CsPbI3 nanosheets are synthesized by hot injection or room temperature stirring. The CsPbCl3, CsPbBr3, and CsPbI3 nanosheets are mixed according to the preset ratio to obtain mixed perovskite nanosheets. The mixing method can be, but is not limited to, stirring ultrasonication.

[0071] S140 , applying the mixed light absorbing material to the surface of the channel layer away from the substrate to obtain an optical floating gate layer.

[0072] Specifically, the mixed light absorbing material (in some embodiments, a mixed perovskite nanosheet) is applied to the surface of the channel layer away from the substrate by spin coating to obtain an optical floating gate layer. The spin coating speed can be but is not limited to 2500 r / min, the spin coating time can be but is not limited to 55 s, and the number of spin coating times can be but is not limited to 10 times.

[0073] The implementation of the present invention includes the following beneficial effects: when the optical floating grating layer receives light of different colors, the optical floating grating layer can form different numbers of photoelectrons according to the wavelength of the light. The photoelectrons are injected into the channel layer, causing the carriers in the channel layer to change, forming current levels of different magnitudes. The current is transmitted to an external acquisition card or detection device through the first electrode and the second electrode. The external acquisition card can identify the color based on the correspondence between the current and the color. There is no need to build a system of multiple filters and acquisition cards. Different colors can be recognized on the same device. The structure is simple, the integration is high, and the recognition speed can be improved and the power consumption can be reduced.

[0074] The present invention can adjust the concentration and preset ratio of the light absorbing material according to needs to customize the range of characteristic wavelengths, and achieve different wavelength distinction and color recognition on the same device.

[0075] like Figure 3-Figure 4 As shown, Figure 3 It is an ultraviolet-visible absorption spectrum of an optical floating gate device. In the figure, line 1 is the ultraviolet-visible absorption spectrum of CsPbCl3 nanosheets, line 2 is the ultraviolet-visible absorption spectrum of CsPbBr3 nanosheets, and line 3 is the ultraviolet-visible absorption spectrum of CsPbI3 nanosheets. It can be seen from the figure that each perovskite nanosheet and the mixed perovskite nanosheet exhibit characteristic absorption behavior at wavelengths of 405nm, 532nm and 635nm, respectively. That is, the mixed perovskite nanosheet combines the wavelength absorption characteristics of each perovskite nanosheet, indicating that this mixture will not affect the absorption performance of the perovskite nanosheet itself, and at the same time indicates that the mixed perovskite nanosheet is stable.

[0076] Figure 4 This is a schematic diagram of the response behavior of an optical floating gate device to three characteristic wavelengths of light. Through the changes in the source-drain current in the figure, it can be concluded that the optical floating gate device achieves a step-by-step increase in photoelectric flux under the excitation of 405nm, 532nm and 635nm wavelength light (405nm corresponds to 10 -10 A. 532nm corresponds to 10 -9 A. 635nm corresponds to 10 -8 A) shows that under the irradiation of light of different wavelengths, the optical floating gate device can generate different and distinguishable currents, indicating that different wavelengths of light can be distinguished based on the current.

[0077] In some embodiments, the present invention provides a method for applying a color-recognizing optical floating gate device, wherein the color-recognizing optical floating gate device is applied to extract color features of a color image, comprising the following steps:

[0078] S210 , obtaining a pulse sequence corresponding to the color image according to the color image; inputting the pulse sequence into an optical floating gate device array, and detecting an electrical signal sequence generated by the optical floating gate device array.

[0079] The optical floating gate device array is composed of a number of the aforementioned optical floating gate devices, and the pulse sequence is a light sequence of a color image.

[0080] For example, a 1*5 optical floating gate device array is constructed, and the source electrode and drain electrode of each optical floating gate device in the optical floating gate device array are bonded to a PCB board respectively, and connected to the acquisition card through the pins of the PCB board.

[0081] Specifically, a color image includes multiple colors. The color image can be segmented according to a certain resolution to obtain the light of the color corresponding to each small part of the color image. The light of all colors corresponding to the color image is a pulse sequence. The pulse sequence is projected onto the optical floating gate device array according to a certain pattern, and the acquisition card is used to detect the electrical signal sequence generated by the optical floating gate device array, such as Figure 5 As shown, Figure 5 This is a flow chart of the reservoir calculation of an optical floating gate device. f1-f3 represent the probability distribution of the recognition output for red light, blue light, and green light, respectively. Assume that a color image is divided into 3*3 images, and each row of pixels in the mixed image 3*3 is a unit. For example, the color in the unit is red-green-blue. For red, the light sequence is 100 (1 represents the input of light) and green is 010. Then, the first row of programmed sequence is input into the 1*5 array of optical floating gate devices for stimulation. Each pulse sequence corresponds to the output of a light signal. For the red part of the entire image, the photocurrent is distributed in 10 -10 For the three rows of pixel units in the image, the output results of each row are different, and different colors also have different current magnitude distributions.

[0082] S220: Obtain color features of a color image according to the electrical signal sequence.

[0083] Specifically, the collected electrical signal sequence is fed as the input layer into a trained neural network. The trained neural network can be, but is not limited to, an echo state neural network. The input electrical signal sequence is nonlinearly mapped into a high-dimensional space. Within this space, no weights between the input and the reservoir or between nodes within the reservoir need to be updated. The trained neural network generates probability distributions corresponding to the three colors red, green, and blue. The output of the neural network is represented by a probability distribution.

[0084] During the training process of a trained neural network, only the reservoir-output weights need to be updated during the training process. In simple terms, the training process is to transmit the input signal to the reservoir for random node-node training, and then obtain the output weight information. The linear regression algorithm is used to update the output weight, and training is performed again. As the number of training times increases, the probability distribution becomes more concentrated.

[0085] like Figure 6 As shown, Figure 6 This figure shows the results of verifying the reservoir computing capability of an optical floating gate device. To verify the reservoir computing capability of the optical floating gate device, the present invention programmed 405nm, 532nm, and 635nm wavelength light into pulse sequences corresponding to 000, 001, ..., 111 and input them into the optical floating gate device. The application of this device in reservoir computing for color image recognition was explored. Figure 6 The results show that the photocurrent of the optical floating gate device is clearly distinguishable under the programming sequence corresponding to each light wavelength. At the same time, due to the different distribution of the pulse sequence, the read current of the optical floating gate device at 10 seconds also shows distinguishable states, demonstrating its application potential in 3-bit reservoir computing. In addition, the device's read state at 10 seconds is also distinguishable by orders of magnitude under different light wavelengths, demonstrating its application value in color image recognition and discriminative reservoir computing.

[0086] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present invention. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute a separate or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0087] The above is a specific description of the preferred implementation of the present invention, but the invention is not limited to the embodiments. Those skilled in the art can make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A method for preparing a color-recognizing optical floating gate device, characterized in that: The following steps are involved: preparing a first electrode and a second electrode on a substrate; forming a channel layer, and disposing the channel layer within a preset range of the substrate; The channel layer is used to modulate carriers inside the channel layer under the action of light of different wavelengths, and the channel layer covers the first electrode and the second electrode; Mixing at least three light absorbing materials in a preset ratio to obtain a mixed light absorbing material, wherein each light absorbing material is used to absorb light of a different wavelength; Tailoring the spectral response by varying the concentration and ratio of three or more hybrid nanosheets, where each nanosheet has different optical properties across different wavelength ranges; adjusting the ratio of the three hybrid nanosheets; Regulate the position, bandwidth and peak value of characteristic absorption peaks; Regulating the concentration and mixing ratio of each type of nanosheet; each type of nanosheet has a specific absorption wavelength, and by adjusting the ratio, the corresponding characteristic absorption wavelength is shifted; In the reservoir calculation, the ratio of the hybrid nanosheets is adjusted in combination with the physical environment of the reservoir; Applying the mixed light absorbing material to the surface of the channel layer away from the substrate to obtain an optical floating gate layer; The optical floating gate layer includes a mixed perovskite nanosheet; the mixed perovskite nanosheet is made by uniformly mixing CsPbBr3 nanosheets, CsPbI3 nanosheets and CsPbCl3 nanosheets in a preset ratio; according to different preset ratios, the mixed perovskite nanosheet has different absorption capabilities for light in different bands; Under the programming sequence corresponding to each light wavelength, the photocurrent of the optical floating gate device is distinguished, the distribution of the pulse sequence is different, and the read current of the optical floating gate device at 10s has a distinguished state.

2. A color-recognizing optical floating gate device, which is obtained by the method for preparing a color-recognizing optical floating gate device according to claim 1, characterized in that: The optical floating gate device includes a substrate, a channel layer, an optical floating gate layer, a first electrode and a second electrode, wherein the channel layer covers a preset range of the substrate, and the optical floating gate layer covers the channel layer, wherein: The optical floating grating layer is used to absorb light of different wavelengths, and the concentration and preset ratio of the light absorbing material can be adjusted to customize the wavelength range; The channel layer is used to modulate carriers inside the channel layer under the action of light of different wavelengths; A first electrode and a second electrode are provided on the substrate, and the channel layer covers the first electrode and the second electrode.

3. The optical floating gate device according to claim 2, wherein: The optical floating grating layer is made of a mixture of at least three light absorbing materials, wherein the at least three light absorbing materials include at least a first light absorbing material, a second light absorbing material and a third light absorbing material. The first light absorbing material is used to absorb light in the blue light band; The second light absorbing material is used to absorb light in the green wavelength band; The third light absorbing material is used to absorb light in the red light band.

4. The optical floating gate device according to claim 2, wherein: The thickness of the optical floating gate layer is in the range of 15-20 nm.

5. The optical floating gate device according to claim 2, wherein: The substrate is made of sapphire and / or quartz.

6. The optical floating gate device according to claim 2, wherein: The substrate is made of a polyethylene terephthalate film and / or a polyimide film.

7. The optical floating gate device according to any one of claims 2 to 6, characterized in that: The material of the channel layer includes a two-dimensional semiconductor material.

8. The optical floating gate device according to any one of claims 2 to 6, characterized in that: The thickness of the channel layer is in the range of 3-5 nm.

9. The optical floating gate device according to any one of claims 2 to 6, characterized in that: The first electrode is a source electrode, the second electrode is a drain electrode, and materials of the source electrode and the drain electrode both include chromium gold.

10. An application method of a color recognition optical floating gate device, characterized in that: Applying the color recognition optical floating gate device to extract color features of a color image comprises the following steps: Obtaining a pulse sequence corresponding to the color image according to the color image; the pulse sequence is a light sequence of the color image; Inputting the pulse sequence into an optical floating gate device array and detecting the electrical signal sequence generated by the optical floating gate device array; the optical floating gate device array is composed of a plurality of optical floating gate devices according to any one of claims 2 to 9; The color characteristics of the color image are obtained according to the electrical signal sequence.

Images