Preparation method and application of tellurene photoelectric detector array

Abstract

The invention provides a preparation method and application of a tellurene photoelectric detector array, and relates to the technical field of photoelectric detector preparation, and the method comprises the steps: sequentially placing an array mask plate and a substrate on a substrate bracket; depositing a tellurium ene layer at the through hole of the array mask plate by using a pulse laser deposition technology, and taking down the array mask plate after deposition to obtain an array consisting of a plurality of pixel units; and sequentially placing an electrode mask plate and a substrate plated with the array on a substrate bracket, depositing an electrode at the through hole by utilizing a physical vapor deposition technology, and connecting the electrode with a reading electrode. According to the method, the tellurene photoelectric detector array is prepared by adopting the pulse laser deposition technology in combination with the mask plate, organic matter such as photoresist or etching liquid does not need to be used, pollution caused by multiple times of spin coating and developing in a traditional photoetching process is avoided, and simple, efficient, low-cost and pollution-free preparation of the tellurene photoelectric detector array can be achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of optoelectronic detector preparation, and particularly relates to a preparation method and application of a tellurene optoelectronic detector array. Background Art

[0002] As a device that converts optical signals into electrical signals, optoelectronic detectors are widely used in fields such as optical communication, image sensing, medical imaging, and lidar. With the development of optoelectronic technology, optoelectronic detector arrays have become an important tool in optoelectronic technology. Array-type optoelectronic detectors can achieve parallel detection and imaging of optical signals by integrating multiple detection units on a single chip.

[0003] Two-dimensional tellurene is a typical narrow-bandgap p-type semiconductor material, and its bandgap can be adjusted with thickness, having strong absorption characteristics for light in the near-infrared and mid-infrared bands. In addition, tellurene also has excellent environmental stability and can stably exist for more than 2 months at room temperature and in an air environment. Therefore, it is an ideal infrared optoelectronic detection material.

[0004] However, the existing tellurene preparation methods mainly include solution synthesis method and mechanical exfoliation method, both of which are not suitable for large-scale and array growth of tellurene. On the other hand, traditional array growth methods mainly use molecular beam epitaxy or chemical vapor deposition methods, which generally require the combination of technologies such as photolithography or laser etching. Among them, photolithography technology has high costs, complex equipment, and inevitably requires multiple spin-coatings of organic substances such as photoresist. The process is cumbersome, easy to introduce pollutants, and the resolution is limited by the ultraviolet light wavelength, with strict requirements for materials. Although the laser etching method has the characteristics of non-contact processing, can flexibly process various shapes and materials, and has strong adaptability, the equipment is expensive, the processing efficiency is low, and it may cause thermal effects to affect the substrate material. Summary of the Invention

[0005] The purpose of the present invention is to provide a preparation method and application of a tellurene optoelectronic detector array, which can achieve simple, efficient, low-cost, and pollution-free preparation of tellurene optoelectronic detector arrays.

[0006] To achieve the above purpose, the present invention is realized through the following technical solutions:

[0007] A preparation method of a tellurene optoelectronic detector array includes the following steps:

[0008] S1: Place the array mask plate and the substrate on the substrate bracket in sequence;

[0009] S2: Deposit a tellurene layer at the through holes of the array mask plate by using pulsed laser deposition technology. After the deposition is completed, remove the array mask plate to obtain an array composed of several pixel units;

[0010] S3: Place the electrode mask plate and the substrate coated with the array on the substrate carrier in sequence, deposit electrodes at the through holes by using physical vapor deposition technology, and connect the electrodes to the readout electrodes.

[0011] Further: Before the step S1, it also includes: Place the mask plate and the substrate in acetone, deionized water, isopropyl alcohol, and absolute ethanol in sequence for ultrasonic cleaning for at least 5 minutes, and after cleaning, blow dry with dry inert gas.

[0012] Further: The substrate carrier has holes corresponding to the shape of the substrate for carrying the substrate and the mask plate; the substrate and the mask plate are stacked in the holes of the substrate carrier.

[0013] Further: The array mask plate includes hollow patterns arranged side by side in sequence at a set spacing, the shape of the hollow patterns is square, circular or rectangular, and the thickness of the mask plate is less than 50 μm.

[0014] Further: The array mask plate includes N×N hollow patterns arranged side by side in sequence at a set spacing, where N is an integer from 5 to 2048; when the hollow pattern is circular, its diameter is 5 μm to 1000 μm; when the hollow pattern is square or rectangular, its side length is 5 μm to 1000 μm.

[0015] Further: The electrode mask plate includes hollow patterns arranged side by side in sequence at a set spacing, the hollow patterns include a device electrode region and a lead connection region, where the pattern shape of the device electrode region is square, circular, rectangular or interdigital, and the lead connection region is used to connect the device electrode region to the readout electrode, and the thickness of the mask plate is less than 50 μm.

[0016] Further: The pattern of the electrode mask plate is aligned with the position of the array on the substrate.

[0017] Further: The electrodes are gold, platinum and their alloys or ITO electrodes.

[0018] The present invention also provides an application of the above preparation method, which is applied to the preparation of a tellurene photodetector array. The tellurene photodetector array includes a number of pixel units arranged side by side in sequence at a set spacing. Each pixel unit is connected to source and drain electrodes, and the source and drain electrodes are connected to the readout electrodes.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. The present invention prepares a tellurene photodetector array by using a pulsed laser deposition technique combined with a mask plate method. Without using organic substances such as photoresist or etching solution, it avoids the contamination that may be introduced in steps such as multiple spin coatings and development in traditional photolithography processes, and significantly improves the device preparation quality.

[0021] 2. The present invention ensures a tight fit between the mask plate and the substrate by setting holes corresponding to the shape of the substrate on the substrate bracket and stacking the substrate and the mask plate therein, which is beneficial to improving the accuracy and uniformity of the tellurene array pattern.

[0022] 3. The mask plate used in the present invention has a thickness of less than 50 μm and contains a precisely designed hollow pattern, which can achieve a controllable pattern size from 5 μm to 1000 μm, meeting the pixel size requirements of different application scenarios; at the same time, the mask plate can be reused, significantly reducing the preparation cost.

[0023] 4. The electrode mask plate adopted by the present invention includes the design of the device electrode area and the lead connection area, which can form the connection circuit with the readout electrode while depositing the electrode, simplifies the device preparation process, and improves the preparation efficiency. Description of the Drawings

[0024] Figure 1 It is a schematic flow chart of a preparation method of a tellurene photodetector array in an embodiment of the present invention;

[0025] Figure 2 It is a design diagram of the array mask plate adopted in another embodiment;

[0026] Figure 3 It is a design diagram of the electrode mask plate adopted in another embodiment;

[0027] Figure 4 It is a schematic diagram of the process of preparing the array in another embodiment;

[0028] Figure 5 It is an optical micrograph of the tellurene array prepared before depositing the electrode in another embodiment; Detailed Embodiments

[0029] Next, the technical solutions of the present invention will be clearly and completely described in conjunction with the drawings. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative work shall fall within the protection scope of the present invention.

[0030] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0031] The present invention provides a method for preparing a tellurene photodetector array. By combining the pulsed laser deposition technique with the mask method, the large-scale preparation of the tellurene array is realized. The masks used in the present invention include two types: an array mask and an electrode mask. Among them, the array mask is used to form the tellurene array structure, and the electrode mask is used to deposit the electrodes and their connection lines. By providing special holes on the substrate carrier to carry the substrate and the mask, and using the method of pressing with a cover plate, it is ensured that the mask is closely attached to the substrate, thereby ensuring the accuracy of the deposited pattern. This method does not require the use of chemicals such as photoresist and developer in the traditional lithography process, avoids the introduction of pollutants, and the mask can be reused, having the advantages of simple process, low cost, and environmental friendliness.

[0032] The above is a simple introduction to the present invention. The following will describe the present invention in detail through specific embodiments.

[0033] A method for preparing a tellurene photodetector array, as Figure 1 shown, includes the following steps:

[0034] S1: Place the array mask and the substrate on the substrate carrier in sequence;

[0035] S2: Use the pulsed laser deposition technique to deposit a tellurene layer at the through holes of the array mask. After the deposition is completed, remove the array mask to obtain an array composed of a plurality of pixel units;

[0036] S3: Place the electrode mask and the substrate coated with the array on the substrate carrier in sequence. Use the physical vapor deposition technique to deposit electrodes at the through holes and connect the electrodes to the readout electrodes.

[0037] Among them, as Figure 2 shown, the substrate carrier is provided with holes corresponding to the shape of the substrate for carrying the substrate and the mask. The substrate and the mask are stacked in sequence in the holes of the substrate carrier, and are pressed tightly by a cover plate to ensure close fitting. Subsequently, use the pulsed laser deposition technique to deposit a tellurene layer through the through holes of the array mask to form an array structure.

[0038] In some embodiments, before the step S1, the following steps are further included: sequentially placing the mask plate and the substrate in acetone, deionized water, isopropyl alcohol, and absolute ethanol for ultrasonic cleaning for at least 5 minutes, and after cleaning, drying with dry inert gas.

[0039] In other embodiments, the substrate carrier has holes corresponding to the shape of the substrate for carrying the substrate and the mask plate; the substrate and the mask plate are stacked in the holes of the substrate carrier.

[0040] In other embodiments, the array mask plate includes hollow patterns arranged in parallel in sequence at a set spacing, the shape of the hollow pattern is square, circular or rectangular, and the thickness of the mask plate is less than 50 μm.

[0041] Among them, the array mask plate includes N×N hollow patterns arranged in parallel in sequence at a set spacing, where N is an integer from 5 to 2048; when the hollow pattern is circular, its diameter is 5 μm to 1000 μm; when the hollow pattern is square or rectangular, its side length is 5 μm to 1000 μm. In this embodiment, it is preferably, as Figure 1 shown, the mask plate size is 10×10 mm, the array is 5×5, the pixel size is 1×1 mm, and the pixel pitch is 1 mm.

[0042] As Figure 3 shown, in other embodiments, the electrode mask plate includes hollow patterns arranged in parallel in sequence at a set spacing, the hollow pattern includes a device electrode region and a lead connection region, wherein, the pattern shape of the device electrode region can be square, circular, rectangular or interdigital, and the lead connection region is used to connect the device electrode region to the readout electrode. In this embodiment, the device electrode region adopts an interdigital pattern. The thicknesses of both mask plates are less than 50 μm to ensure that the material to be deposited can smoothly pass through the hollow pattern and be deposited on the substrate or the array surface during the deposition process. The pattern of the electrode mask plate is aligned with the position of the array on the substrate; the electrode is a gold, platinum and their alloys or ITO electrode.

[0043] In another embodiment, the present invention also provides an application of the above preparation method, which is applied to the preparation of a tellurene photodetector array, the tellurene photodetector array includes a plurality of pixel units arranged in parallel in sequence at a set spacing, each pixel unit is connected to source and drain electrodes, and the source and drain electrodes are connected to the readout electrode.

[0044] The preparation method of the present invention will be described in detail below with a specific implementation step:

[0045] As Figure 4 shown, first, Si / SiO 2The substrate and two kinds of mask plates are sequentially placed in propanol, deionized water, isopropanol, and absolute ethanol for ultrasonic cleaning. The cleaning times are 10 minutes, 15 minutes, 15 minutes, and 15 minutes respectively. After cleaning, the surface is dried with high-purity nitrogen.

[0046] Then, place the array mask plate and the substrate on the substrate carrier, and press them tightly with the cover plate to ensure close fitting. Place the substrate carrier in the coating chamber of the pulsed laser deposition equipment, and evacuate the chamber until the air pressure in the chamber is less than 10 -5 Pa. Heat the substrate to 150 °C and then start deposition. Use a high-purity Te target, with a laser frequency of 1 Hz, a laser energy of 100 mJ, and 60 laser pulses. After deposition, cool it naturally to room temperature to obtain a tellurene array. See Figure 5 the optical micrograph shown, which shows the tellurene array prepared before depositing the electrodes.

[0047] Finally, replace the mask plate with an interdigital electrode mask plate, place it together with the tellurene array in the substrate holder, and press it tightly with the cover plate to ensure that each interdigital electrode coincides with the pixel. Place the substrate holder in the vacuum chamber, and evacuate the chamber until the air pressure in the chamber is less than 10 -5 Pa. After heating the substrate to 150 °C, first deposit a Cr contact layer. Use a high-purity Cr target, with a laser frequency of 1 Hz, a laser energy of 200 mJ, and 1000 laser pulses. Then replace the target with a gold target, set the laser frequency to 1 Hz, the laser energy to 200 mJ, and the number of laser pulses to 3000. Finally, obtain a tellurene array device plated with Au / Cr electrodes.

[0048] It should be noted that the preparation method of the present invention can also adopt other modified design schemes. For example: first deposit the bottom electrode using the electrode mask plate, then deposit tellurene using the array mask plate, and finally deposit the top electrode using the electrode mask plate to obtain a tellurene photodetector array with a bottom electrode and a top electrode structure.

[0049] The tellurene photodetector array obtained by the above preparation method includes a plurality of pixel units arranged in parallel at a set spacing in sequence. Each pixel unit is connected to source and drain electrodes, and the source and drain electrodes are connected to a readout electrode, which can be used for infrared photodetection.

[0050] The above embodiments are only for explaining the technical concept and features of the present invention, and their purpose is to enable those familiar with this technology to understand the content of the present invention and implement it accordingly. It cannot be used to limit the protection scope of the present invention. Any equivalent transformation or modification made according to the spirit of the present invention should be covered within the protection scope of the present invention.

Claims

1. A method for preparing a tellurene photodetector array, characterized in that: The following steps are involved: S1: placing the array mask plate and the substrate on the substrate bracket in sequence; S2: Depositing a tellurene layer at the through holes of the array mask plate by using a pulsed laser deposition technique, and removing the array mask plate after the deposition is completed to obtain an array consisting of a plurality of pixel units; S3: placing the electrode mask plate and the substrate coated with the array on a substrate bracket in sequence, depositing electrodes at the through holes using a physical vapor deposition technique, and connecting the electrodes to the readout electrodes.

2. The method for preparing a tellurene photodetector array according to claim 1, characterized in that: Before step S1, the method further includes: placing the mask plate and the substrate in acetone, deionized water, isopropanol and anhydrous ethanol in sequence for ultrasonic cleaning for at least 5 minutes, and drying them with dry inert gas after cleaning.

3. The method for preparing a tellurene photodetector array according to claim 1, characterized in that: The substrate bracket has holes corresponding to the shape of the substrate, which are used to carry the substrate and the mask plate; The substrate and the mask plate are stacked in the hole of the substrate bracket.

4. The method for preparing a tellurene photodetector array according to claim 1, characterized in that: The array mask plate includes hollow patterns arranged in parallel in sequence according to a set interval, the hollow patterns are in the shape of a square, a circle or a rectangle, and the mask plate has a thickness of less than 50 μm.

5. The method for preparing a tellurene photodetector array according to claim 4, characterized in that: The array mask plate includes N×N hollow patterns arranged in parallel in sequence according to a set spacing, where N is an integer from 5 to 2048; when the hollow pattern is circular, its diameter is 5μm to 1000μm; when the hollow pattern is square or rectangular, its side length is 5μm to 1000μm.

6. The method for preparing a tellurene photodetector array according to claim 1, characterized in that: The electrode mask plate includes hollow patterns arranged in parallel in sequence according to a set spacing, and the hollow pattern includes a device electrode area and a lead connection area, wherein the pattern shape of the device electrode area is square, circular, rectangular or interdigitated, and the lead connection area is used to connect the device electrode area with the readout electrode, and the mask plate thickness is less than 50μm.

7. The method for preparing a tellurene photodetector array according to claim 1, characterized in that: The pattern of the electrode mask is aligned with the position of the array on the substrate.

8. The method for preparing a tellurene photodetector array according to claim 1, characterized in that: The electrode is gold, platinum or its alloy or ITO electrode.

9. An application of the preparation method according to any one of claims 1 to 7, characterized in that: The invention is applied to prepare a tellurene photodetector array, wherein the tellurene photodetector array comprises a plurality of pixel units which are sequentially arranged in parallel at a set interval, wherein the pixel units are all connected to source-drain electrodes, and the source-drain electrodes are connected to a readout electrode.

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