High-performance infrared photoelectric transistor detector with silver telluride quantum dot / ZnO semiconductor structure and preparation method thereof

Abstract

The invention provides a quantum dot phototransistor capable of realizing high-performance infrared detection and a preparation process of the quantum dot phototransistor, and belongs to the field of photoelectric components. Comprising a substrate, a metal electrode pair, a ZnO film and Ag2Te quantum dots which are arranged in sequence, and a high-speed center spin-coating method is adopted. The high-performance photoelectric detector based on the Ag2Te colloidal quantum dots is prepared by adopting a high-speed center spin-coating method technology, the detector has a simple transistor structure of Ag2Te / ZnO, carrier transport is accelerated through regulation and control of grid voltage and channel voltage, the performance of the device is further improved, the device has excellent performance from visible light to near infrared light, and the photoelectric detector has good application prospects. And under the incident light of 660 nm, the response rate (2050 A / W) and the detection rate (4.8 * 10 < 13 > Jones) are ultrahigh, and under the incident light of 940 nm, the response rate (2450 A / W) and the detection rate (6.8 * 10 < 13 > Jones) are ultrahigh.

Description

Technical Field

[0001] The invention relates to an infrared phototransistor detector, in particular to a high-performance infrared phototransistor with an Ag2Te quantum dot / ZnO structure and a preparation method thereof, belonging to the technical field of photoelectric components. Background Art

[0002] Infrared rays can be divided into near-infrared light band (760-3000nm), mid-infrared band (3-50μm) and far-infrared band (50-1000μm). Among them, near-infrared photodetection devices are widely used in military fields such as navigation, night vision, weapon detection, as well as civilian fields such as biomedical imaging, optical communications, and atmospheric monitoring, and have very broad prospects. Quantum dot materials can be prepared by solution method, and the absorption band can be regulated and cover the near-infrared band. The preparation is simple, so they are used in the field of near-infrared photodetection. Commonly used infrared photodetectors can be divided into photoconductors, photodiodes, phototransistors, etc. Among them, photodiodes have small dark current and fast response speed, but low external quantum efficiency, which cannot exceed 100%. Phototransistors and photoconductors have optical gain, so they can have high external quantum efficiency and obtain high-performance photodetectors. Summary of the invention

[0003] In view of this, an object of the present invention is to provide a quantum dot phototransistor and a preparation process thereof that can achieve high-performance infrared detection.

[0004] In order to achieve the above-mentioned invention object, the present invention provides the following technical solutions: a high-performance infrared phototransistor detector with an Ag2Te quantum dot / ZnO structure and a preparation method thereof, comprising a substrate, a metal electrode pair, a ZnO thin film precursor solution, Ag2Te quantum dots, a high-speed center spin coating method, and a gate electrode arranged in sequence.

[0005] Preferably, the substrate is a P-type heavily doped silicon wafer containing silicon dioxide.

[0006] Preferably, the quantum dot layer includes a layer of quantum dot film, the quantum dot film is an Ag2Te quantum dot film containing surface ligands, and the thickness of the infrared quantum dot layer is 100-200 nm.

[0007] The present invention also provides a high-performance infrared phototransistor of the Ag2Te quantum dot / ZnO structure described in the above technical solution and a preparation method thereof, comprising the following steps: Provide 100ml three-necked flask, tellurium powder, silver acetate, OTT, TBP, oleylamine, octadecene, and two 10ml separatory bottles.

[0008] 0.04 mmol of tellurium powder, 4 ml of oleylamine and 5 ml of TBP were added to the separatory bottle, and the mixture was shaken thoroughly to make the tellurium powder evenly suspended in the mixed solution to form a tellurium precursor.

[0009] 0.334 g of silver acetate, 1.4 ml of OTT, and 10 ml of octadecene were added to the three-necked flask, and then the interface was sealed with sealing glue.

[0010] The mixture in the three-necked flask was heated and stirred at 130°C in a N2 atmosphere to remove water and oxygen from the solution.

[0011] Add 2.5 ml of octadecene and 1.5 ml of tellurium precursor into the above separatory bottle and mix thoroughly. Then slowly inject the mixed solution into the three-necked flask and keep the temperature to react for 10 minutes.

[0012] The mixed solution after the above reaction was purified by precipitation using ethanol as a non-solvent and toluene as a solvent.

[0013] Preferably, in step (3), the gas needs to be evacuated and nitrogen needs to be injected into the three-necked flask multiple times to ensure the removal of water and oxygen in the flask.

[0014] Preferably, the step (4) needs to be completed in a nitrogen glove box to prevent oxidation of the tellurium powder.

[0015] Provide substrate, metal electrode pair, Ag2Te quantum dots and ZnO precursor solution, and gate electrode.

[0016] Plasma treatment is performed on the substrate to enhance its wettability.

[0017] The ZnO precursor solution is spin-coated on the substrate at a high speed, and annealed to form a semiconductor layer.

[0018] A pair of metal electrodes is covered on the substrate on which the ZnO film is spin-coated to form a source and a drain.

[0019] Ag2Te quantum dots are spin-coated at high speed on the substrate coated with electrodes to serve as a light absorbing layer of the channel.

[0020] Preferably, the plasma treatment in step (1) is performed for 10 min, and the spin coating in step (2) is performed in a nitrogen glove box, and obtaining the ZnO semiconductor layer further comprises: requiring a central spin coating speed of 3000 rpm, heating the ZnO semiconductor layer in a nitrogen glove box, the heating temperature being 300° C., and the heating time being 30 min.

[0021] Preferably, the evaporation speed in step (3) is 0.3 angstroms / second and the thickness is 60 nm.

[0022] Preferably, the spin coating in step (4) is carried out in a nitrogen glove box, and obtaining the Ag2Te quantum dot light absorbing layer also includes: requiring the central spin coating speed to be 2500r / min, heating the Ag2Te quantum dot light absorbing layer in the nitrogen glove box, the heating temperature is 120°C, and the heating time is 30min.

[0023] The present invention provides a quantum dot phototransistor capable of realizing high-performance infrared detection and a preparation process thereof, belonging to the field of optoelectronic components. The invention comprises a substrate, a metal electrode pair, a ZnO film, an Ag2Te quantum dot, and a high-speed center spin coating method which are arranged in sequence. The invention adopts a high-speed center spin coating method technology to prepare a high-performance photodetector based on Ag2Te colloidal quantum dots. The detector has a simple transistor structure of Ag2Te / ZnO / Si. By regulating the gate voltage and the channel voltage, the carrier transmission is accelerated, thereby improving the performance of the device, so that the device has excellent performance from visible light to near infrared, and has an ultra-high response rate (2050 A / W) and a detection rate (4.8×10 11 Jones). BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0025] Figure 1 This is a structural diagram of a high-performance infrared phototransistor detector with an Ag2Te quantum dot / ZnO structure in Example 1 of the present invention.

[0026] Figure 2 The transfer characteristic curves of the high-performance infrared phototransistor detector with Ag2Te quantum dot / ZnO structure in Example 1 of the present invention at different light powers tested under 660nm illumination.

[0027] Figure 3 This is the time-current curve of the high-performance infrared phototransistor detector with Ag2Te quantum dot / ZnO structure in Example 1 of the present invention tested under 660nm light.

[0028] Figure 4 The transfer characteristic curves of the high-performance infrared phototransistor detector with Ag2Te quantum dot / ZnO structure in Example 1 of the present invention at different light powers tested under 940nm illumination.

[0029] Figure 5 The time-current curve of the high-performance infrared phototransistor detector of Ag2Te quantum dot / ZnO structure in Example 1 of the present invention tested under 940nm light DETAILED DESCRIPTION

[0030] The present invention provides a high-performance infrared phototransistor detector with a Ag2Te quantum dot / ZnO structure and a preparation method thereof, comprising a substrate, a metal electrode pair, a ZnO film precursor solution, Ag2Te quantum dots, a high-speed center spin coating method, and a gate electrode which are arranged in sequence.

[0031] In the present invention, the high-performance infrared phototransistor detector of the Ag2Te quantum dot / ZnO structure is characterized in that the detector has a high responsivity (2050 A / W), and compared with PbS quantum dots, Ag2Te quantum dots have higher electron migration ability and lower toxicity.

[0032] In the present invention, the high-speed center spin coating is for ZnO semiconductor layer thin film, and the spin coating speed is preferably 3000 r / min. The high-speed center spin coating is for Ag2Te light absorbing layer thin film, and the spin coating speed is preferably 2500 r / min.

[0033] The present invention provides a quantum dot phototransistor capable of realizing high-performance infrared detection and a preparation process thereof, belonging to the field of optoelectronic components. The invention comprises a substrate, a metal electrode pair, a ZnO film, an Ag2Te quantum dot, and a high-speed center spin coating method which are arranged in sequence. The invention adopts a high-speed center spin coating method technology to prepare a high-performance photodetector based on Ag2Te colloidal quantum dots. The detector has a simple transistor structure of Ag2Te / ZnO / Si. By regulating the gate voltage and the channel voltage, the carrier transmission is accelerated, thereby improving the performance of the device, so that the device has excellent performance from visible light to near infrared, and has an ultra-high response rate (2050 A / W) and a detection rate (4.8×10 11 Jones).

[0034] The present invention also provides a high-performance infrared photoelectric transistor of the Ag2Te quantum dot / ZnO structure described in the above technical solution and a preparation method thereof, comprising the following steps: providing a substrate, a metal electrode pair, Ag2Te quantum dots and ZnO precursor solution, and a gate electrode.

[0035] Plasma treatment is performed on the substrate to enhance its wettability.

[0036] The ZnO precursor solution is spin-coated on the substrate at a high speed, and annealed to form a semiconductor layer.

[0037] A pair of metal electrodes is covered on the substrate on which the ZnO film is spin-coated to form a source and a drain.

[0038] Ag2Te quantum dots are spin-coated at high speed on the substrate coated with electrodes to serve as a light absorbing layer of the channel.

[0039] The present invention provides a ZnO precursor solution. In the present invention, the ZnO precursor solution preferably includes ZnO powder and ammonia water. In the present invention, the amount ratio of the ZnO powder to the ammonia water is 10 mol: 1 mol, and simple mixing and dissolving can be sufficient. In the present invention, the ZnO powder and ammonia water can be commercially available products well known to those skilled in the art. In the present invention, the ZnO purity is preferably 99.99%, and the ammonia water is purchased from Sigma-Aldrich.

[0040] In the present invention, a ZnO semiconductor layer is prepared on a P-type heavily doped silicon wafer of silicon dioxide by spin coating.

[0041] In the present invention, the spin coating is preferably performed on a coater. In the present invention, the rotation speed of the coater is preferably 3000 r / min, and the rotation time is preferably 30 s.

[0042] In the present invention, the spin coating is preferably performed in a nitrogen glove box, and after the semiconductor layer is obtained, it is heated at 300° C. for 30 minutes.

[0043] The present invention covers metal source and drain electrodes at fixed positions on the surface of the semiconductor layer. The present invention has no special limitation on the operation of covering the metal electrode pair, and the technical solution for preparing electrodes well known to those skilled in the art can be used. In the present invention, the method of covering the metal electrode pair is preferably evaporation, and more preferably vacuum evaporation. In the present invention, the temperature of the vacuum evaporation is preferably 1000~1200℃, more preferably 1050~1150℃; the time of the vacuum evaporation is preferably 20~30min, more preferably 24-26 min; the vacuum degree of the vacuum evaporation is preferably 4~5×10 -4 Pa. In the present invention, the target material during the evaporation is preferably aluminum.

[0044] After the metal source and drain are prepared, the present invention uses a spin coating method to prepare an Ag2Te quantum dot light absorption layer in the channel between the source and drain of the transistor.

[0045] In the present invention, the spin coating is preferably performed on a coating machine. In the present invention, the rotation speed of the coating machine is preferably 2000-2500 r / min, more preferably 2500 r / min, and the rotation time is preferably 60 s.

[0046] In the present invention, the spin coating is preferably performed in a nitrogen glove box, and after the light absorbing layer is obtained, it is heated at 120° C. for 30 minutes.

[0047] In the present invention, the quantum dot phototransistor is preferably used under an inert condition without water or oxygen. The present invention has no special limitation on the connection method of the quantum dot phototransistor, and any method of connecting the quantum dot phototransistor to a power source known to those skilled in the art can be used.

[0048] The following is a detailed description of a high-performance infrared phototransistor having a Ag2Te quantum dot / ZnO structure and a preparation method thereof provided by the present invention in conjunction with the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0049] Embodiment 1:

[0050] 24 mg of ZnO powder and 3 ml of ammonia water were placed in a 5 ml sample bottle and stirred to obtain a ZnO precursor solution. 4 ml of Ag2Te quantum dot crude solution and 15 ml of acetone were placed in a 30 ml centrifuge tube and centrifuged at 9000 r / min for five minutes, the supernatant was discarded, and 2 ml of toluene was used to disperse the quantum dot precipitate. In the present invention, the sample bottle needs to be cleaned with acetone, isopropanol and deionized water before use. The present invention uses acetone, isopropanol and deionized water once each in sequence.

[0051] The obtained ZnO precursor solution is spin-coated on a P-type heavily doped silicon wafer of silicon dioxide in a nitrogen glove box by a coating machine to obtain a ZnO semiconductor layer. The rotation speed of the coating machine is preferably 3000 rpm, and the rotation time is preferably 30 seconds. The semiconductor layer is heated in a nitrogen glove box, and the heating temperature is preferably 300° C., and the heating time is preferably 30 minutes.

[0052] The silicon wafer with the ZnO semiconductor layer is attached to a mask of a specific shape, and a 60nm thick aluminum electrode is vacuum-deposited as the source and drain electrodes.

[0053] The obtained Ag2Te quantum dot solution is spin-coated in the transistor channel by a coater in a nitrogen glove box. The rotation speed of the coater is preferably 2500 r / min, and the rotation time is preferably 60 s. The Ag2Te is heated in a nitrogen glove box, and the heating temperature is preferably 120° C., and the heating time is preferably 30 min.

[0054] The structure diagram of the high-performance infrared phototransistor with Ag2Te quantum dots / ZnO structure in this embodiment is shown in FIG. Figure 1 shown.

[0055] In this embodiment Figure 2 The transfer characteristic curves of the high-performance infrared phototransistor detector of Ag2Te quantum dot / ZnO structure in Example 1 of the present invention at different optical powers tested under 660nm illumination are shown in FIG. Figure 2 The Ag2Te quantum dot / ZnO high-performance infrared phototransistor has an ultra-high response rate (2050A / W) and detection rate (4.8×10 13 Jones).

[0056] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

[0057] Embodiment 2:

[0058] 24 mg of SnO powder and 3 ml of ammonia water were placed in a 5 ml sample bottle and stirred to obtain a SnO precursor solution. 4 ml of the crude Ag2Te quantum dot solution and 15 ml of acetone were placed in a 30 ml centrifuge tube and centrifuged at 9000 r / min for five minutes, the supernatant was discarded, and the quantum dot precipitate was dispersed with 2 ml of toluene. In the present invention, the sample bottle needs to be cleaned with acetone, isopropanol and deionized water before use. The present invention uses acetone, isopropanol and deionized water once each in sequence.

[0059] The obtained SnO precursor solution is spin-coated on a P-type heavily doped silicon wafer of silicon dioxide in a nitrogen glove box by a spin coater to obtain a SnO semiconductor layer. The rotation speed of the spin coater is preferably 3000 rpm, and the rotation time is preferably 30 seconds. The semiconductor layer is heated in a nitrogen glove box, and the heating temperature is preferably 300° C., and the heating time is preferably 30 minutes.

[0060] The silicon wafer with the SnO semiconductor layer is attached to a mask of a specific shape, and a 60nm thick aluminum electrode is vacuum-deposited as the source and drain electrodes.

[0061] The obtained Ag2Te quantum dot solution is spin-coated in the transistor channel by a coater in a nitrogen glove box. The rotation speed of the coater is preferably 2500 r / min, and the rotation time is preferably 60 s. The Ag2Te is heated in a nitrogen glove box, and the heating temperature is preferably 120° C., and the heating time is preferably 30 min.

[0062] Embodiment 3:

[0063] 24 mg of IGO powder and 3 ml of ammonia water were placed in a 5 ml sample bottle and stirred to obtain an IGO precursor solution. 4 ml of Ag2Te quantum dot crude solution and 15 ml of acetone were placed in a 30 ml centrifuge tube and centrifuged at 9000 r / min for five minutes, the supernatant was discarded, and 2 ml of toluene was used to disperse the quantum dot precipitate. In the present invention, the sample bottle needs to be cleaned with acetone, isopropanol and deionized water before use. The present invention uses acetone, isopropanol and deionized water once each in sequence.

[0064] The obtained IGO precursor solution is spin-coated on a P-type heavily doped silicon wafer of silicon dioxide in a nitrogen glove box by a spin coater to obtain an IGO semiconductor layer. The rotation speed of the spin coater is preferably 3000 rpm, and the rotation time is preferably 30 seconds. The semiconductor layer is heated in a nitrogen glove box, and the heating temperature is preferably 300° C., and the heating time is preferably 30 minutes.

[0065] The silicon wafer with the IGO semiconductor layer is attached to a mask of a specific shape, and a 60nm thick aluminum electrode is vacuum-deposited as the source and drain electrodes.

[0066] The obtained Ag2Te quantum dot solution is spin-coated in the transistor channel by a coater in a nitrogen glove box. The rotation speed of the coater is preferably 2500 r / min, and the rotation time is preferably 60 s. The Ag2Te is heated in a nitrogen glove box, and the heating temperature is preferably 120° C., and the heating time is preferably 30 min.

[0067] Embodiment 4:

[0068] 24 mg of IGZO powder and 3 ml of ammonia water were placed in a 5 ml sample bottle and stirred to obtain an IGZO precursor solution. 4 ml of the crude Ag2Te quantum dot solution and 15 ml of acetone were placed in a 30 ml centrifuge tube and centrifuged at 9000 r / min for five minutes, the supernatant was discarded, and the quantum dot precipitate was dispersed with 2 ml of toluene. In the present invention, the sample bottle needs to be cleaned with acetone, isopropanol and deionized water before use. The present invention uses acetone, isopropanol and deionized water once each in sequence.

[0069] The obtained IGZO precursor solution is spin-coated on a P-type heavily doped silicon wafer of silicon dioxide in a nitrogen glove box by a coating machine to obtain an IGZO semiconductor layer. The rotation speed of the coating machine is preferably 3000 rpm, and the rotation time is preferably 30 seconds. The semiconductor layer is heated in a nitrogen glove box, and the heating temperature is preferably 300° C., and the heating time is preferably 30 minutes.

[0070] The silicon wafer with the IGZO semiconductor layer is attached to a mask of a specific shape, and a 60nm thick aluminum electrode is vacuum-deposited as the source and drain electrodes.

[0071] The obtained Ag2Te quantum dot solution is spin-coated in the transistor channel by a coater in a nitrogen glove box. The rotation speed of the coater is preferably 2500 r / min, and the rotation time is preferably 60 s. The Ag2Te is heated in a nitrogen glove box, and the heating temperature is preferably 120° C., and the heating time is preferably 30 min.

Claims

1. A high-performance infrared phototransistor detector with a silver telluride quantum dot / ZnO semiconductor structure and a preparation method thereof, comprising a substrate, a metal source and drain, a ZnO metal oxide semiconductor film and a silver telluride quantum dot film, and a gate electrode arranged in sequence. The ZnO metal oxide semiconductor film is characterized in that a ZnO precursor solution is prepared by a solution method, spin-coated onto a substrate, annealed at 250-300°C to crystallize it, and the film thickness is 25-35nm. The silver telluride quantum dot is characterized in that the quantum dot size is between 3.0nm and 5.0nm.

2. The high-performance infrared phototransistor detector with silver telluride quantum dots / ZnO semiconductor structure according to claim 1 is characterized by its excellent photoelectric capability. It is widely used in infrared photoelectric detection, optical synapses, visual imaging, human health characteristics monitoring (blood oxygen, pulse) and other applications.

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