Absorption-enhanced ultraviolet detector and preparation method thereof

Abstract

The absorption-enhanced ultraviolet detector comprises a glass substrate, an anode layer, a hole transport layer, a ZnSe-coated ZnS quantum dot ultraviolet absorption layer dissolved in PMMA, an electron transport layer, a ZnO / Ag NW conductive anti-reflection layer which is dissolved in a PDMS solution and is of a hexagonal close-packed micro-column array structure, and a semitransparent cathode from bottom to top in sequence. According to the invention, the transmission optical path of incident light in the device is increased through the reflection increasing and antireflection effect of the anode layer, the antireflection effect of the ZnO / Ag NW conductive antireflection layer of the hexagonal close-packed micro-column array structure dissolved in the PDMS solution on incident light, and the reflection cavity formed by the anode and the ZnO / Ag NW conductive antireflection layer of the hexagonal close-packed micro-column array structure dissolved in the PDMS solution; the incident light utilization rate is increased; and a local plasmon resonance effect of the ZnSe-ZnS quantum dot ultraviolet absorption layer dissolved in the PMMA and a local plasmon resonance effect of the ZnSe-ZnS quantum dot ultraviolet absorption layer dissolved in the PMMA can jointly and effectively improve the incident light utilization efficiency of the detector.

Description

Technical Field

[0001] The invention belongs to the technical field of ultraviolet detection and relates to an absorption-enhanced ultraviolet detector and a preparation method thereof. Background Art

[0002] Ultraviolet rays appear in the tail flames of rocket and missile engines, corona discharge of high-voltage transmission lines, extreme thunderstorms, flame combustion and other processes, and ultraviolet rays can be used as signal sources for confidential communications, light sources for ultraviolet curing and ultraviolet sterilization, etc., which are closely related to national defense security and all aspects of social life. Therefore, detecting ultraviolet rays is conducive to helping people improve their research capabilities in astrophysical analysis, missile warning, high-voltage transmission line inspection, atmospheric ozone research, extreme weather warning, environmental pollution monitoring, fire warning, mineral exploration and mining, medical care and ultraviolet communication, etc., and is of great significance to national defense security and people's daily production and life. Therefore, ultraviolet detection technology has great research value in many research directions in the defense and civilian fields.

[0003] However, due to defects in the device structure, existing UV detectors have problems such as low efficiency in absorbing UV light incident on the device surface, which in turn affects the further improvement of the photoelectric properties of the UV detector, such as light response, detection rate and quantum efficiency, and ultimately limits the further development of the entire detector industry. Summary of the invention

[0004] (I) Purpose of the invention

[0005] The purpose of the present invention is to provide an absorption-enhanced ultraviolet detector and a preparation method thereof, aiming to solve the shortcomings of current ultraviolet detectors such as low energy conversion efficiency due to low absorption rate of incident light in the ultraviolet band.

[0006] (II) Technical solution

[0007] In order to solve the above technical problems, the present invention provides an absorption-enhanced ultraviolet detector, which comprises, from bottom to top, a glass substrate, an anode layer, a hole transport layer, a ZnSe@ZnS quantum dot ultraviolet absorption layer dissolved in PMMA, an electron transport layer, a ZnO / Ag NW conductive anti-reflection layer with a hexagonal close-packed micro-column array structure dissolved in PDMS solution, and a semi-transparent cathode.

[0008] The present invention also provides a method for preparing an absorption-enhanced ultraviolet detector, and the preparation process is as follows: first, depositing metal Ag / Au with a thickness of 20 to 40 nm as an anode layer on a clean glass substrate treated with ultraviolet radiation, then preparing a hole transport layer with a thickness of 40 to 70 nm, and then spin-coating a PMMA solution of ZnSe@ZnS with a thickness of 30 to 50 nm as an ultraviolet absorption layer, and then depositing an electron transport layer with a thickness of 10 to 30 nm by thermal evaporation, and then preparing a ZnO / Ag NW with a hexagonal close-packed micro-column array structure dissolved in a PDMS solution with a thickness of 35 to 45 nm by spin coating as a conductive anti-reflection layer, and finally thermally evaporating and depositing a semi-transparent cathode electrode Ca / Ag with a thickness of 10 to 30 nm.

[0009] (III) Beneficial effects

[0010] The absorption-enhanced ultraviolet detector and preparation method provided by the above technical solution increase the transmission optical path of the incident light inside the device through the reflection-enhancing and transmission-reduction effect of the anode layer, the transmission-enhancing and transmission-reduction effect of the ZnO / Ag NW conductive transmission-reduction layer dissolved in the PDMS solution with a hexagonal close-packed micro-column array structure on the incident light, and the reflection cavity formed by the anode and the ZnO / Ag NW conductive transmission-reduction layer dissolved in the PDMS solution with a hexagonal close-packed micro-column array structure, thereby increasing the utilization rate of the incident light; and the localized plasmon resonance effect of the ZnSe@ZnS quantum dot ultraviolet absorption layer dissolved in PMMA; together, the incident light utilization efficiency of the detector is effectively improved, and the shortcomings of the current ultraviolet detector, such as low energy conversion efficiency due to low absorption rate of incident light in the ultraviolet band, are solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a schematic diagram of the structure of an ultraviolet detector with enhanced absorption according to an embodiment of the present invention.

[0012] Figure 2 Top view of the hexagonal close-packed micropillar array structure.

[0013] Figure 3 for Figure 2 Side view of. DETAILED DESCRIPTION

[0014] In order to make the purpose, content and advantages of the present invention more clear, the specific implementation methods of the present invention are further described in detail below in conjunction with the drawings and examples.

[0015] Reference Figures 1 to 3 As shown, the absorption-enhanced ultraviolet detector of this embodiment includes, from bottom to top, a glass substrate 1, an anode layer 2, a hole transport layer 3, a ZnSe@ZnS quantum dot ultraviolet absorption layer 4 dissolved in PMMA, an electron transport layer 5, a ZnO / AgNW conductive anti-reflection layer 6 with a hexagonal close-packed micro-column array structure dissolved in PDMS solution, and a semi-transparent cathode 7.

[0016] The ZnSe@ZnS quantum dot ultraviolet absorption layer 4 dissolved in PMMA is a thin layer having a local plasmon resonance effect formed by ZnSe@ZnS quantum dots with a core-shell structure dissolved in PMMA.

[0017] The ZnO / Ag NW conductive anti-reflection layer 6 with a hexagonal close-packed micro-column array structure dissolved in the PDMS solution is located between the semi-transparent cathode 7 and the electron transport layer 5. It is a conductive thin layer composed of a PDMS solution of ZnO / AgNW. The above conductive thin layer has a hexagonal close-packed micro-column array structure and has the function of increasing the transmittance of incident light and transmitting electrons.

[0018] The anode layer 2 is made of metal, alloy or other conductive materials that have the function of increasing reflection and reducing transmission of ultraviolet light.

[0019] The translucent cathode 7 is a translucent structure made of metal or alloy, which has the function of increasing the transmittance of incident light.

[0020] The anode layer 2 and the ZnO / Ag NW conductive anti-reflection layer 6 having a hexagonal close-packed micro-column array structure dissolved in the PDMS solution can form a reflection cavity, increase the transmission optical path of the incident light inside the device, and thus increase the utilization rate of the incident light.

[0021] The preparation process of the absorption-enhanced ultraviolet detector in this embodiment is as follows: first, a metal Ag / Au with a thickness of 20 to 40 nm is deposited on a clean glass substrate treated with ultraviolet radiation as an anode layer, then a hole transport layer with a thickness of 40 to 70 nm is prepared, and then a PMMA solution of ZnSe@ZnS with a thickness of 30 to 50 nm is spin-coated as an ultraviolet absorption layer, and then a 10 to 30 nm thick electron transport layer is deposited by thermal evaporation, and then a hexagonal close-packed microcolumn array structure of ZnO / AgNW dissolved in a PDMS solution with a thickness of 35 to 45 nm is prepared by spin coating as a conductive anti-reflection layer, and finally a 10 to 30 nm thick semi-transparent cathode electrode Ca / Ag is deposited by thermal evaporation.

[0022] Example

[0023] The preparation process of the absorption-enhanced UV detector is as follows: first, a 30 nm thick metal Ag / Au is deposited on a clean glass substrate treated with UV radiation as an anode layer, then a 60 nm thick hole transport layer is prepared, and then a 40 nm thick ZnSe@ZnS PMMA solution is spin-coated as a UV absorption layer, followed by a 20 nm thick electron transport layer deposited by thermal evaporation, and then a 40 nm thick hexagonal close-packed micro-column array structure of ZnO / Ag NW dissolved in PDMS solution is prepared by spin coating as a conductive anti-reflection layer, and finally a 20 nm thick semi-transparent cathode electrode Ca / Ag is deposited by thermal evaporation.

[0024] 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 technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. An absorption-enhanced ultraviolet detector, characterized in that: From bottom to top, it includes: glass substrate, anode layer, hole transport layer, ZnSe@ZnS quantum dot ultraviolet absorption layer dissolved in PMMA, electron transport layer, ZnO / Ag NW conductive anti-reflection layer with hexagonal close-packed micro-column array structure dissolved in PDMS solution, and semi-transparent cathode.

2. The absorption enhanced ultraviolet detector according to claim 1, characterized in that: The ZnSe@ZnS quantum dot ultraviolet absorption layer dissolved in PMMA is a thin layer with a local plasmon resonance effect formed by dissolving ZnSe@ZnS quantum dots with a core-shell structure in PMMA.

3. The absorption enhanced ultraviolet detector according to claim 2, characterized in that: The ZnO / AgNW conductive anti-reflection layer of the hexagonal close-packed micro-column array structure dissolved in the PDMS solution is a conductive thin layer composed of the PDMS solution of ZnO / AgNW.

4. The absorption enhanced ultraviolet detector according to claim 3, characterized in that: The conductive thin layer has a hexagonal close-packed micro-column array structure.

5. The absorption enhanced ultraviolet detector according to claim 4, characterized in that: The anode layer is made of metal or alloy which has the function of increasing reflection and reducing transmission of ultraviolet light.

6. The absorption enhanced ultraviolet detector according to claim 5, characterized in that: The translucent cathode is a translucent structure made of metal or alloy, which increases the transmittance of incident light.

7. The absorption enhanced ultraviolet detector according to claim 6, characterized in that: The anode layer and the ZnO / Ag NW conductive anti-reflection layer of the hexagonal close-packed micro-column array structure dissolved in the PDMS solution form a reflection cavity, which increases the transmission optical path of the incident light inside the device and increases the utilization rate of the incident light.

8. A method for preparing the absorption-enhanced ultraviolet detector according to claim 7, characterized in that: The preparation process is as follows: first, a metal Ag / Au layer with a thickness of 20 to 40 nm is deposited on a clean glass substrate treated with ultraviolet radiation as an anode layer, then a hole transport layer with a thickness of 40 to 70 nm is prepared, and then a PMMA solution of ZnSe@ZnS with a thickness of 30 to 50 nm is spin-coated as an ultraviolet absorption layer, and then a 10 to 30 nm thick electron transport layer is deposited by thermal evaporation, and then a 35 to 45 nm thick ZnO / Ag NW with a hexagonal close-packed microcolumn array structure dissolved in a PDMS solution is prepared by spin coating as a conductive anti-reflection layer, and finally a 10 to 30 nm thick semi-transparent cathode electrode Ca / Ag is deposited by thermal evaporation.

9. The method for preparing the absorption enhanced ultraviolet detector according to claim 8, characterized in that: The preparation process is as follows: first, a 30nm thick metal Ag / Au is deposited on a clean glass substrate treated with ultraviolet radiation as an anode layer, then a 60nm thick hole transport layer is prepared, and then a 40nm thick ZnSe@ZnS PMMA solution is spin-coated as an ultraviolet absorption layer, followed by a 20nm thick electron transport layer deposited by thermal evaporation, and then a 40nm thick hexagonal close-packed microcolumn array structure of ZnO / Ag NW dissolved in PDMS solution is prepared by spin coating as a conductive anti-reflection layer, and finally a 20nm thick semi-transparent cathode electrode Ca / Ag is deposited by thermal evaporation.

10. Application of the method for preparing the absorption-enhanced ultraviolet detector according to claim 8 or 9 in ultraviolet detection technology.

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