Photoelectric detector based on anisotropic photo-thermal electric material, preparation method and encryption method

Abstract

The application belongs to the technical field of information encryption, and discloses a photoelectric detector based on anisotropic photo-thermoelectric material, a preparation method and an encryption method.The prepared photoelectric detector has a very small volume and is suitable for miniaturized application.The material is convenient to integrate into a microelectronic device and helps to improve the integration of the device.The material shows significant advantages in the microelectronic field, especially in reducing device size and improving integration.The photoelectric detector based on the anisotropic photo-thermoelectric material generally has high sensitivity, is conducive to detecting weak light signals, and has excellent photoelectric conversion performance, and can realize efficient photoelectric detection.The encryption method of the application generates a key with high complexity and uniqueness by diversifying the combination of preset polarization angles and positions, so that different information can correspond to different polarization angle and position combinations, so that the system has high flexibility and scalability.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of information encryption, and particularly relates to a photoelectric detector based on anisotropic photo-thermoelectric material, a preparation method and an encryption method. BACKGROUND

[0002] Compared with traditional materials, high-performance low-dimensional thermoelectric materials have attracted extensive attention due to their high speed, economy and scalability. In particular, one-dimensional materials experience enhanced boundary scattering at their large boundary interfaces due to their sharp size reduction, which changes their low-frequency acoustic modes, thereby having a significant impact on their thermal conductivity performance, improving the performance of photo-thermoelectric devices. As a typical quasi-one-dimensional photo-thermoelectric material, Nb3Se 12 The I lattice structure shows chain characteristics and experiences two structural phase transitions at low temperatures, resulting in abnormal behaviors in physical properties such as thermal conductivity, dielectricity and infrared absorption. In addition, the increase of the transverse-to-longitudinal ratio of one-dimensional materials makes them have excellent response to polarized light.

[0003] With the rapid development of information technology, although informatization brings great convenience to our daily life, the rapid spread of information also exacerbates information security problems, which not only affects the daily life of ordinary people, but also has a profound impact on key fields such as politics, economy and military. Therefore, it is urgent to develop a new method that can achieve high-level information encryption. SUMMARY

[0004] The purpose of the present application is to overcome the above-mentioned deficiencies, and to provide a photoelectric detector based on anisotropic photo-thermoelectric material, a preparation method and an encryption method. By dynamically modulating the photo-thermoelectric current according to the polarization state, optical imaging is realized, so as to convert the encrypted information into identifiable polarization state. This method combines high-capacity information transmission with complex encryption technology, which is of great significance to meet the growing demand for secure data communication.

[0005] In order to achieve the above-mentioned purpose, the technical scheme adopted by the present application is as follows:

[0006] In a first aspect, the present application provides a preparation method of a photoelectric detector based on anisotropic photo-thermoelectric material, comprising the following steps:

[0007] Obtaining raw materials, extracting Nb3Se 12 I crystal raw materials into a vacuum tube, and finally growing to obtain anisotropic photo-thermoelectric material;

[0008] The anisotropic photo-thermoelectric material is peeled off onto a silicon oxide sheet, and photoresist is coated on the surface of the anisotropic photo-thermoelectric material on the silicon oxide sheet. A hollow pattern with double-end electrodes is photoetched on the photoresist.

[0009] Depositing a Cr layer and an Au layer with a desired thickness on a silicon oxide wafer, and after peeling, a photoelectric detector based on Nb3Se 12 I nanowire.

[0010] The further improvement of the present application is that the Nb3Se 12 I crystal raw material is Nb powder, Se powder and I2 crystal with a stoichiometric purity of 99.999%, and 2mg / cm 3 I2 as a transport agent;

[0011] The Nb3Se 12 I crystal raw material is placed in a quartz tube for vacuum sealing and melting, and the vacuum degree is 5*10 -4 Pa.

[0012] During growth, the Nb3Se 12 I crystal raw material has one end as an evaporation end and the other end as a growth end, the temperature of the evaporation end and the growth end is set to 600 DEG C and 480 DEG C respectively, the temperature is raised at a rate of 1.3 DEG C / min from room temperature, the growth time is 14 days, and the preparation of the anisotropic photothermal electric material is completed.

[0013] The further improvement of the present application is that a 5nm Cr layer and a 60nm Au layer are deposited on a silicon oxide wafer by using a resistance type thermal evaporation technology.

[0014] The further improvement of the present application is that when peeling, the silicon oxide wafer after deposition is soaked in an acetone solution to separate the photoresist from the silicon oxide wafer, then the silicon oxide wafer is taken out and soaked in isopropyl alcohol to remove the acetone, and the silicon oxide wafer is washed clean with deionized water, and a photoelectric detector based on Nb3Se 12 I nanowire.

[0015] In the second aspect, the present application provides a photoelectric detector based on an anisotropic photothermal electric material, which is prepared by the preparation method of the photoelectric detector based on the anisotropic photothermal electric material.

[0016] In the third aspect, the present application provides an encryption method of a photoelectric detector based on an anisotropic photothermal electric material, which comprises the following steps:

[0017] The polarization angle corresponding to each information is preset, and the position and polarization angle of the laser are preset according to the required information;

[0018] The photoelectric detector based on Nb3Se 12 I nanowire is irradiated by the preset laser through a half-wave plate, a corresponding polarization state is formed on the surface of the photoelectric detector, and the photocurrent change under different positions and the photocurrent change under different polarization angles are obtained;

[0019] The photoelectric current changes at different positions and the photoelectric current changes at different polarization angles are fitted as the key of the photoelectric detector.

[0020] The application further improves the specific method of presetting the polarization angle corresponding to each information as follows:

[0021] According to the required preset laser position and polarization angle, the photoelectric current values generated at different positions are fitted, and each degree of the polarization angle from 0 degrees to 90 degrees is assigned an ASCII code.

[0022] The application further improves that the photoelectric current changes at different positions are obtained by adjusting the position of the laser, thereby adjusting the incident position of the incident light, and the incident light at different incident positions irradiates the Nb3Se 12 I nanowire photoelectric detector, the photoelectric current changes at different positions are obtained.

[0023] The application further improves that the photoelectric current changes at different polarization angles are obtained by adjusting the half-wave plate to control the polarization angle of the incident light, and the incident light at different polarization angles irradiates the Nb3Se 12 I nanowire photoelectric detector, the photoelectric current changes at different polarization angles are obtained.

[0024] The application further improves that the photoelectric current changes at different positions and the photoelectric current changes at different polarization angles are fitted as the key of the photoelectric detector, and the specific method is as follows:

[0025] While adjusting the laser position, the polarization angle of the laser is continuously adjusted through the half-wave plate, so that the photoelectric current values output by the linear light trajectory irradiation on the Nb3Se 12 I nanowire photoelectric detector remain consistent, thereby obtaining the fitted photoelectric current response curve, and the photoelectric current change relationship of the incident light at different polarization angles at different positions is taken as the key of the Nb3Se 12 I nanowire photoelectric detector.

[0026] Compared with the prior art, the application has the following beneficial effects:

[0027] The Nb3Se 12 I nanowire photoelectric detector prepared by the application is based on a quasi-one-dimensional nanowire structure material, which has a very small volume and is suitable for miniaturized applications. This material is easy to integrate into microelectronic devices, which helps to improve the integration of the device. This material shows significant advantages in the field of microelectronics, especially in reducing device size and improving integration. The photoelectric detector based on anisotropic photothermal electric material generally has high sensitivity, which is conducive to detecting weak light signals, and has excellent photoelectric conversion performance, and can realize efficient photoelectric detection.

[0028] The encryption method of the present application has high flexibility and scalability by diversifying the combination of preset polarization angles and positions, different information can correspond to different polarization angle and position combinations, so that the system has high flexibility and scalability, the generated key has high complexity and uniqueness, and it is difficult to be cracked, by selecting a specific polarization angle and position combination, the system can effectively distinguish and resist noise and interference in the environment, and improve the reliability of encryption, the encryption method of the present application is based on Nb3Se 12 I nanowire photodetector has high sensitivity and can accurately detect weak photocurrent changes to ensure data accuracy during encryption, and the photodetector using nanowire structure can realize miniaturization and high integration, which helps to deploy the encryption system in a compact space. The present application forms a key by laser irradiation of a photo-thermal-electric material, and adopts a double cooperative encryption principle to significantly improve the security of information. The information decrypter must simultaneously master the photo-thermal-electric characteristics of the material and the accurate matching relationship of the polarization angle, so as to correctly analyze the polarization angle information in the encrypted information. This encryption method makes it extremely difficult for unauthorized information reading, effectively preventing illegal access and leakage of information. The present application has important application prospect in the field of information security, especially in microelectronic devices requiring high security and high integration. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 The preparation flowchart of the photodetector based on anisotropic photo-thermal-electric material in the present application is shown in the figure.

[0030] Figure 2 The encryption method flowchart of the photodetector in the present application is shown in the figure.

[0031] Figure 3 The optical image of the photo-thermal-electric material Nb3Se 12 I crystal prepared in Example 1 of the present application is shown in the figure.

[0032] Figure 4 The device structure diagram of the double-end photodetector based on Nb3Se 12 I prepared in Example 1 of the present application is shown in the figure.

[0033] Figure 5 The relationship diagram of photocurrent and incident laser polarization angle of the photodetector prepared in Example 1 of the present application is shown in the figure.

[0034] Figure 6 The photocurrent response curve of the device irradiated by straight line light track in Example 1 of the present application is shown in the figure.

[0035] Figure 7 The photocurrent response curve of the device irradiated by straight line light track in Example 1 of the present application is shown in the figure.

[0036] Figure 8 The device schematic diagram for the encryption and decryption process of the heat and polarization cooperation in embodiment 1 of the application.

[0037] Figure 9 The encryption and decryption process of the hidden information in embodiment 1 of the application. DETAILED DESCRIPTION

[0038] In order to enable the person skilled in the art to better understand the application scheme, the technical scheme in the embodiment of the application will be described clearly and completely in the following with reference to the drawings in the embodiment of the application. Obviously, the described embodiment is only a part of the embodiment of the application, not all. Based on the embodiment in the application, all other embodiments obtained by the person skilled in the art without creative labor should belong to the protection scope of the application.

[0039] It should be noted that the terms "first", "second" and the like in the specification and claims of the application and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the application described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not necessarily limit to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0040] The application will be described in further detail below with reference to the drawings:

[0041] Referring to Figure 1 The preparation method of the photoelectric detector based on the anisotropic photo-thermoelectric material comprises the following steps:

[0042] S1, obtaining Nb3Se 12 I crystal raw material, Nb3Se 12 I crystal raw material is vacuumized and sealed in a tube, and finally grown to obtain an anisotropic photo-thermoelectric material.

[0043] S2, stripping the anisotropic photo-thermoelectric material onto a silicon oxide sheet, coating photoresist on the surface of the anisotropic photo-thermoelectric material on the silicon oxide sheet, and photoetching a hollow pattern with double-end electrodes on the photoresist.

[0044] S3, depositing a Cr layer and an Au layer with a required thickness on the silicon oxide sheet, and after stripping, obtaining a Nb3Se 12Photoelectric detector of I nanowire.

[0045] Referring to Figure 2 , the encryption method of the photoelectric detector based on anisotropic photothermoelectric material comprises the following steps:

[0046] S1, preset the polarization angle corresponding to each information, and preset the position and polarization angle of the laser according to the required information.

[0047] S2, according to the preset position and polarization angle of the laser, the half-wave plate is used to irradiate the photoelectric detector based on Nb3Se 12 I nanowire, form the corresponding polarization state on the surface of the photoelectric detector, and obtain the photocurrent change under different positions and the photocurrent change under different polarization angles.

[0048] S3, fitting the photocurrent change under different positions and the photocurrent change under different polarization angles as the key of the photoelectric detector.

[0049] A photoelectric detector based on anisotropic photothermoelectric material is prepared by the preparation method of the photoelectric detector based on anisotropic photothermoelectric material.

[0050] Embodiment 1:

[0051] The preparation method of the photoelectric detector based on anisotropic photothermoelectric material comprises the following steps:

[0052] Step one, synthesis of anisotropic photothermoelectric material.

[0053] Weighing: weigh 1g, 3.6g, and 0.6g of Nb powder, Se powder, and I2 crystal with a purity of 99.999% as raw materials for synthesizing Nb3Se 12 I crystal.

[0054] Sealing tube: mix the powder of the weighed raw materials and place them in a single-end sealed quartz tube with an inner diameter of 2cm and a length of 20cm, then install the quartz tube on a vacuum sealing machine, and after the pressure reaches 5×10 -4 Pa, seal and fuse the quartz tube by high temperature sintering.

[0055] Growth: place the high-temperature fused vacuum quartz tube in a double-temperature zone tube furnace, where one end containing the raw materials is placed in the evaporation end and the other end is placed in the growth end, and the temperature of the evaporation end and the growth end is set to 600℃ and 480℃ respectively, the heating rate is 1.3℃ / min, the growth time is 14 days, and the synthesis of anisotropic photothermoelectric material is completed. The crystal material of the anisotropic photothermoelectric material obtained after growth is shown in Figure 3 .

[0056] Step two, based on anisotropic photo-thermal electric material lithography double electrode.

[0057] The anisotropic photo-thermal electric material obtained in step one is placed on a transparent tape, and is prepared on a 285 nm thick silicon oxide sheet by mechanical peeling method. Subsequently, the silicon oxide sheet is spin-coated with AZ5214 photoresist, and a hollow pattern with double electrodes is prepared by maskless lithography technology.

[0058] Step three, preparation of double-end photoelectric detector.

[0059] A 5 nm Cr layer and a 60 nm Au layer are deposited on the silicon oxide sheet by resistive thermal evaporation technology, with deposition rates of 0.1 A / s and 0.5 A / s, respectively. And Finally, the deposited silicon oxide sheet is soaked in a 50-degree acetone solution for 2 hours, and then a rubber head dropper is used to gently blow the silicon oxide sheet soaked in acetone, so that the photoresist and the silicon oxide sheet are separated. Then the silicon oxide sheet is taken out and soaked in isopropanol for 1 minute to remove acetone, and then the silicon oxide sheet is washed with deionized water to obtain a photoelectric detector based on Nb3Se 12 I nanowire, and the device structure diagram is shown in Figure 4 .

[0060] Example 2:

[0061] The encryption method of the photoelectric detector based on anisotropic photo-thermal electric material includes the following steps

[0062] Step one, preset the polarization angle corresponding to each information, and preset the position and polarization angle of the laser according to the required information.

[0063] According to the preset position and polarization angle of the laser, the photocurrent values generated at different positions are fitted, and each degree from 0 degrees to 90 degrees of the polarization angle is assigned an ASCII code.

[0064] Step two, according to the preset position and polarization angle of the laser, irradiate the photoelectric detector based on Nb3Se 12 I nanowire through a half-wave plate, form the corresponding polarization state on the surface of the photoelectric detector, and obtain the photocurrent change at different positions and the photocurrent change at different polarization angles.

[0065] The laser system uses a 532 nm wavelength laser by placing a half-wave plate in the incident light path.

[0066] 1. Control the laser incident position to obtain the photocurrent change curve caused by different polarization angles

[0067] By rotating the half-wave plate, the polarization direction of the laser is dynamically adjusted, and the relationship between the incident laser polarization angle and the photocurrent is precisely controlled. The relevant data and diagrams are shown in Figure 5 .

[0068] 2. Remove the half-wave plate and adjust the laser incident position to obtain the photocurrent change at different positions.

[0069] By moving the laser source, the laser is irradiated on the Nb3Se 12 I nanowire photodetector along a straight path, and the photocurrent response curve is recorded, as shown in Figure 6 .

[0070] 3. While moving the laser, adjust the position of the half-wave plate to compensate for the change in photocurrent due to laser movement, so that the photocurrent generated remains constant, thereby obtaining the fitted photocurrent response curve, which shows the same photocurrent value, as shown in Figure 7 .

[0071] Step three, fit the photocurrent change at different positions and the photocurrent change at different polarization angles as the key of the photodetector.

[0072] Take the same photocurrent value, the compensation polarization angle corresponding to different incident positions. Different polarization angles are respectively corresponding to different ASCII codes, and information is hidden in the optical image in this way, as shown in Table 1.

[0073] Table 1: Numerical table of ASCII code corresponding to polarization angle

[0074]

[0075] As shown in Figure 8 , in the present application, the "XDU" image encapsulates 30 different polarization states through polarization compensation technology, so that complex information is hidden in the image.

[0076] Example 3:

[0077] The plaintext is encrypted using a symmetric encryption strategy, and the specific process is as follows:

[0078] Determine the plaintext: the information "WILEY" that needs to be encrypted.

[0079] Encryption: input the plaintext and key into the encryption algorithm to generate ciphertext. The ciphertext is the encrypted data and cannot be directly read.

[0080] For the "WILEY" information that needs to be encrypted and transmitted, the five ASCII letters "W", "I", "L", "E", and "Y" correspond to the polarization angles of 52°, 38°, 41°, 34°, and 54°, respectively. The specific polarization angle polarization state encoding obtained by the polarization compensation technology from the "XDU" image is associated with the five angles of 52°, 38°, 41°, 34°, and 54°, respectively.

[0081] According to the five angles of 52°, 38°, 41°, 34°, and 54°, the light emitted by the photodetector based on the Nb3Se 12 I nanowire is irradiated, the corresponding polarization state is formed on the surface of the electrical detector, and the photocurrent change at different positions and the photocurrent change at different polarization angles are obtained;

[0082] The photocurrent change at different positions and the photocurrent change at different polarization angles are fitted as the key of the photodetector.

[0083] In the decryption process, the key lies in the coupling between the thermoelectric properties and the polarization properties of the photo-thermoelectric material. For example, in the scenario where Sophia knows the location of the specific encrypted information, she can use the relationship between the photo-thermoelectric properties and the polarization fitting as the key to decrypt and reveal the "WILEY" information hidden in the ordinary "XDU" image. From Bob's perspective, the image may only appear as a regular image obtained by a computer or other detector.

[0084] In addition, as Figure 9 shown, the method of the present application can also be extended to general imaging techniques. First, the thermoelectric properties are used to process the conventional single-point imaging results, and then the polarization state is adjusted for compensation, thereby hiding information in the ordinary imaging results on the surface. This method allows a large amount of information to be encoded in a single image, combined with the ultra-wide band detection capability of the Nb3Se 12 I material that is not limited by the band gap, significantly enhancing the capacity and security of data transmission. The present application is expected to promote the wide application of anisotropic photo-thermoelectric devices in the field of information encryption and anti-counterfeiting technology.

[0085] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application and not to limit it, although the present application has been described in detail with reference to the above examples, those skilled in the art should understand that the specific embodiments of the present application can be modified or replaced, without departing from the spirit and scope of the present application. Any modification or equivalent replacement, which should be covered within the protection scope of the claims of the present application.

Claims

1. A method for fabricating a photodetector based on anisotropic photothermoelectric materials, characterized in that, Includes the following steps: Obtain Nb3Se 12 I crystal raw material, Nb3Se 12 I. The crystal raw material is vacuum-sealed and then grown to obtain anisotropic photothermal and electric materials. Anisotropic photothermal materials are peeled off onto a silicon oxide wafer, photoresist is coated on the surface of the anisotropic photothermal materials on the silicon oxide wafer, and a hollow pattern with double-ended electrodes is photolithographically formed on the photoresist. A Cr and Au layer of the required thickness is deposited on a silicon oxide wafer. After peeling, a Nb3Se-based product is obtained. 12 I-nanowire photodetectors.

2. The method for fabricating a photodetector based on anisotropic photothermal materials according to claim 1, characterized in that, Nb3Se 12 The raw materials for I crystals are Nb powder, Se powder, and I₂ crystals with a stoichiometric purity of 99.999% and a concentration of 2 mg / cm³. 3 I2 is used as a transport medium; Nb3Se 12 I. The crystal raw material is placed into a quartz tube and fused under vacuum at a vacuum level of 5 × 10⁻⁶. -4 Pa; During growth, it contains Nb3Se 12 The crystalline raw material has one end as the evaporation end and the other end as the growth end. The temperatures of the evaporation end and the growth end are set to 600℃ and 480℃, respectively. The heating rate is 1.3℃ / min starting from room temperature, and the growth time is 14 days to complete the preparation of the anisotropic photothermal material.

3. The method for fabricating a photodetector based on anisotropic photothermoelectric materials according to claim 1, characterized in that, A 5nm Cr layer and a 60nm Au layer were deposited on a silicon oxide wafer using resistive thermal evaporation technology.

4. The method for fabricating a photodetector based on anisotropic photothermoelectric materials according to claim 1, characterized in that, During the stripping process, the deposited silicon oxide wafer is immersed in an acetone solution to separate the photoresist from the silicon oxide. The wafer is then removed and immersed in isopropanol to remove the acetone. After rinsing the wafer clean, the Nb3Se-based product is obtained. 12 I-nanowire photodetectors.

5. A photodetector based on anisotropic photothermoelectric materials, characterized in that, The photodetector based on anisotropic photothermal materials was prepared by any one of the methods described in claims 1-4.

6. A method for encryption of photodetectors based on anisotropic photothermal materials, characterized in that, Includes the following steps: The polarization angle corresponding to each piece of information is preset, and the position and polarization angle of the laser are preset according to the required information; Based on the preset laser position and polarization angle, a half-wave plate is used to focus the Nb3Se-based laser. 12 I-nanowire photodetectors are irradiated to form corresponding polarization states on the surface of the photodetectors, and the changes in photocurrent at different positions and at different polarization angles are obtained. The changes in photocurrent at different locations and at different polarization angles are fitted together to serve as the key for the photodetector.

7. The encryption method for a photodetector based on anisotropic photothermal materials according to claim 6, characterized in that, The specific method for presetting the polarization angle corresponding to each piece of information is as follows: Based on the desired preset laser position and polarization angle, the photocurrent values ​​generated at different positions are fitted, and each degree of polarization angle from 0 degrees to 90 degrees is assigned an ASCII code.

8. The encryption method for a photodetector based on anisotropic photothermal materials according to claim 6, characterized in that, The change in photocurrent at different positions is achieved by adjusting the position of the laser, thereby adjusting the incident position of the incident light, and irradiating Nb3Se with incident light at different incident positions. 12 A photodetector using I-nanowires was used to obtain changes in photocurrent at different locations.

9. The encryption method for a photodetector based on anisotropic photothermal materials according to claim 6, characterized in that, The change in photocurrent at different polarization angles is controlled by adjusting the half-wave plate to regulate the polarization angle of the incident light. Different polarization angles of incident light irradiate Nb3Se. 12 A photodetector using I-nanowires was used to obtain changes in photocurrent at different polarization angles.

10. The encryption method for a photodetector based on anisotropic photothermal materials according to claim 6, characterized in that, The steps involve fitting the photocurrent changes at different locations and at different polarization angles to the key of the photodetector. The specific method is as follows: While adjusting the laser position, the polarization angle of the laser is continuously adjusted using a half-wave plate, so that the Nb3Se... 12 On the photodetector of the I-nanowire, the output photocurrent value remains consistent when illuminated along a straight light trajectory, thus obtaining a fitted photocurrent response curve. The photocurrent variation at different locations under incident light with different polarization angles is used as the Nb3Se... 12 The key to photodetectors using I-nanowires.

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