CN117673188A - Self-driven solar blind ultraviolet detector based on asymmetric Schottky barrier - Google Patents
Self-driven solar blind ultraviolet detector based on asymmetric Schottky barrier Download PDFInfo
- Publication number
- CN117673188A CN117673188A CN202311653005.XA CN202311653005A CN117673188A CN 117673188 A CN117673188 A CN 117673188A CN 202311653005 A CN202311653005 A CN 202311653005A CN 117673188 A CN117673188 A CN 117673188A
- Authority
- CN
- China
- Prior art keywords
- layer
- self
- ultraviolet detector
- solar blind
- blind ultraviolet
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 230000004888 barrier function Effects 0.000 title claims abstract description 44
- 229910052751 metal Inorganic materials 0.000 claims abstract description 36
- 239000002184 metal Substances 0.000 claims abstract description 36
- 239000000758 substrate Substances 0.000 claims abstract description 17
- 230000010287 polarization Effects 0.000 claims abstract description 14
- 229910052782 aluminium Inorganic materials 0.000 claims description 16
- 230000000694 effects Effects 0.000 claims description 9
- 238000000151 deposition Methods 0.000 claims description 8
- 239000000463 material Substances 0.000 claims description 8
- 229910052594 sapphire Inorganic materials 0.000 claims description 7
- 239000010980 sapphire Substances 0.000 claims description 7
- 230000008021 deposition Effects 0.000 claims description 6
- 238000005530 etching Methods 0.000 claims description 6
- 238000000034 method Methods 0.000 claims description 5
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 4
- 238000009616 inductively coupled plasma Methods 0.000 claims description 4
- 238000002955 isolation Methods 0.000 claims description 4
- 238000002360 preparation method Methods 0.000 claims description 4
- 239000004411 aluminium Substances 0.000 claims description 3
- 238000005229 chemical vapour deposition Methods 0.000 claims description 3
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims 1
- 238000002488 metal-organic chemical vapour deposition Methods 0.000 claims 1
- 239000004065 semiconductor Substances 0.000 abstract description 6
- 238000000926 separation method Methods 0.000 abstract description 5
- 230000035945 sensitivity Effects 0.000 abstract description 4
- 238000004519 manufacturing process Methods 0.000 abstract description 3
- 230000004043 responsiveness Effects 0.000 abstract description 3
- 239000000969 carrier Substances 0.000 abstract description 2
- 230000015572 biosynthetic process Effects 0.000 abstract 1
- 230000002708 enhancing effect Effects 0.000 abstract 1
- 229910002704 AlGaN Inorganic materials 0.000 description 10
- 230000004044 response Effects 0.000 description 10
- 238000001514 detection method Methods 0.000 description 7
- 230000005684 electric field Effects 0.000 description 6
- 238000010521 absorption reaction Methods 0.000 description 5
- 230000007547 defect Effects 0.000 description 4
- 238000005265 energy consumption Methods 0.000 description 4
- 230000009286 beneficial effect Effects 0.000 description 3
- 238000013461 design Methods 0.000 description 3
- 238000005286 illumination Methods 0.000 description 3
- 230000003595 spectral effect Effects 0.000 description 3
- 239000002131 composite material Substances 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 230000010354 integration Effects 0.000 description 2
- 230000004298 light response Effects 0.000 description 2
- 238000005452 bending Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000004134 energy conservation Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000005693 optoelectronics Effects 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 230000005533 two-dimensional electron gas Effects 0.000 description 1
- 238000000825 ultraviolet detection Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/08—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof in which radiation controls flow of current through the device, e.g. photoresistors
- H01L31/10—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof in which radiation controls flow of current through the device, e.g. photoresistors characterised by potential barriers, e.g. phototransistors
- H01L31/101—Devices sensitive to infrared, visible or ultraviolet radiation
- H01L31/102—Devices sensitive to infrared, visible or ultraviolet radiation characterised by only one potential barrier
- H01L31/108—Devices sensitive to infrared, visible or ultraviolet radiation characterised by only one potential barrier the potential barrier being of the Schottky type
- H01L31/1085—Devices sensitive to infrared, visible or ultraviolet radiation characterised by only one potential barrier the potential barrier being of the Schottky type the devices being of the Metal-Semiconductor-Metal [MSM] Schottky barrier type
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/0248—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies
- H01L31/0256—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies characterised by the material
- H01L31/0264—Inorganic materials
- H01L31/0304—Inorganic materials including, apart from doping materials or other impurities, only AIIIBV compounds
- H01L31/03046—Inorganic materials including, apart from doping materials or other impurities, only AIIIBV compounds including ternary or quaternary compounds, e.g. GaAlAs, InGaAs, InGaAsP
- H01L31/03048—Inorganic materials including, apart from doping materials or other impurities, only AIIIBV compounds including ternary or quaternary compounds, e.g. GaAlAs, InGaAs, InGaAsP comprising a nitride compounds, e.g. InGaN
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/18—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof
- H01L31/184—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof the active layers comprising only AIIIBV compounds, e.g. GaAs, InP
- H01L31/1844—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof the active layers comprising only AIIIBV compounds, e.g. GaAs, InP comprising ternary or quaternary compounds, e.g. Ga Al As, In Ga As P
- H01L31/1848—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof the active layers comprising only AIIIBV compounds, e.g. GaAs, InP comprising ternary or quaternary compounds, e.g. Ga Al As, In Ga As P comprising nitride compounds, e.g. InGaN, InGaAlN
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/18—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof
- H01L31/184—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof the active layers comprising only AIIIBV compounds, e.g. GaAs, InP
- H01L31/1852—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof the active layers comprising only AIIIBV compounds, e.g. GaAs, InP comprising a growth substrate not being an AIIIBV compound
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/50—Manufacturing or production processes characterised by the final manufactured product
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- Electromagnetism (AREA)
- General Physics & Mathematics (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Chemical & Material Sciences (AREA)
- Inorganic Chemistry (AREA)
- Light Receiving Elements (AREA)
Abstract
The invention discloses a self-driven solar blind ultraviolet detector based on an asymmetric Schottky barrier, and belongs to the technical field of semiconductor device manufacturing. The ultraviolet detector comprises the following components in sequence from bottom to top: substrate layer, alN buffer layer, al 0.65 Ga 0.35 N layer, al 0.4 Ga 0.6 N active layer, al 0.55 Ga 0.45 An N barrier layer and a metal electrode layer. The invention uses the electrode and Al on one side only 0.4 Ga 0.6 Inserting Al between N active layers 0.55 Ga 0.45 The N barrier layer forms an asymmetric MSM structure, and different barrier heights are utilized to induce energy bands to bend, so that asymmetric energy bands are formed, separation and transportation of photogenerated carriers are obviously promoted, the problem of high power consumption of the detector with the symmetric MSM structure is solved, and the self-driving characteristic is realized. Formation ofIs an asymmetric heterostructure of (2) enhancing Al 0.4 Ga 0.6 The polarization field of the N layers is further increased, so that the generation of photocurrent is increased, and the responsiveness under 0V is greatly improved. In addition, the screw dislocation density of the epitaxial structure manufactured by the invention is lower, so that the device obtains ultra-low dark current, and the sensitivity of the device is improved.
Description
Technical Field
The invention relates to a self-driven solar blind ultraviolet detector based on an asymmetric Schottky barrier, and belongs to the technical field of semiconductor device manufacturing.
Background
To accommodate the rapid development of modern electronic information, optoelectronic devices are gradually evolving towards "miniaturization" and "integration". Therefore, developing a high-sensitivity, low-energy-consumption and high-response-speed ultraviolet detector is a core of future development in the field. Furthermore, the construction of a self-driven ultraviolet photoelectric detector which can work continuously and does not need an external power supply has become an important research point in the field of photoelectric detection. From the application point of view, the self-driven ultraviolet detector has the special advantages of low energy consumption, energy conservation, environmental protection, small device size, suitability for use under extreme conditions and the like, and is very popular in the fields of forest fire prevention, submarine petroleum leakage monitoring and the like.
Wide band gap semiconductor material Al x Ga 1-x N has adjustable band gap, intrinsic solar blind property, high temperature resistance and excellent chemical and physical stability. In addition, al x Ga 1-x The polarization characteristic of N helps to form a highly conductive two-dimensional electron gas (2 DEG) at the heterojunction interface, thereby improving device performance. In view of these significant advantages, alGaN has become an ideal material for developing high performance ultraviolet detectors. So far, most AlGaN-based ultraviolet detectors adopt an MSM structure due to the advantages of simple and controllable manufacturing process, strong plane integration capability, low noise, high detection rate and the like. Whereas conventional MSM structures use the same metal/semiconductor schottky contact to form symmetric electrodes, resulting in mirror symmetry of the schottky barrier formed across the metal/semiconductor contact. In this case, the photo-generated electrons/holes in the AlGaN semiconductor layer have no preferential drift direction. In other words, although these symmetrical AlGaN-based MSM structure uv detectors have achieved very high photodetection performance, they mostly require an external bias voltage to drive operation, facilitating the separation and transport of photogenerated electron-hole pairs. These external power sources not only add to the complexity of the circuit design and processing costs of the ultraviolet detection system, but also limit their use in particular environments and conditions.
In order to realize self-driving of the ultraviolet detector with the AlGaN-based MSM structure, namely, the ultraviolet detector can be driven to work under zero bias voltage, the common practice is to design an asymmetric structure and obtain an asymmetric Schottky barrier. While it is common practice to implement an asymmetric schottky barrier to deposit different metal contacts at both ends of the device, including using different metal materials and changing the contact area of the metal electrodes. However, the method is unfavorable for flexibility and wear resistance of the device, has the defects of high cost, limited work function difference of Schottky metal and the like, prevents further improvement of asymmetric Schottky barrier and further improvement of device performance, and mainly has low response and detection rate at zero bias because the photocurrent of the device at zero bias voltage is smaller.
Disclosure of Invention
In order to solve the problems of high energy consumption and low sensitivity of the existing AlGaN-based MSM structure ultraviolet detector, the invention provides a self-driven solar blind ultraviolet detector based on an asymmetric Schottky barrier, which is formed by a metal electrode at one sideWith Al 0.4 Ga 0.6 Inserting Al between N active layers 0.55 Ga 0.45 An N barrier layer for forming asymmetric Al with polarization effect 0.55 Ga 0.45 N/Al 0.4 Ga 0.6 N/Al 0.65 Ga 0.35 N heterostructure builds an asymmetric MSM structure, thereby realizing a self-driven AlGaN-based MSM solar blind ultraviolet detector, and because Al with polarization enhancement effect is designed 0.55 Ga 0.45 N/Al 0.4 Ga 0.6 N/Al 0.65 Ga 0.55 N epitaxial structure with enhanced absorption layer Al by controlling polarization 0.4 Ga 0.6 The built-in electric field in N causes interface charge due to polarization effect in the heterostructure, and a strong built-in electric field exists in the AlGaN absorption layer, so that separation of photo-generated electron-hole pairs is promoted, generation of photocurrent is further increased, and responsiveness and detection rate in zero bias are greatly improved.
A self-driven solar blind ultraviolet detector based on an asymmetric schottky barrier, comprising, in order from bottom to top: the substrate layer, the AlN buffer layer, the heterostructure layer and the metal electrode layer; wherein, heterostructure layer includes three high aluminium component layers: al (Al) 0.65 Ga 0.35 N buffer layer, al 0.4 Ga 0.6 N active layer and Al 0.55 Ga 0.45 An N barrier layer; and one side electrode of the self-driven solar blind ultraviolet detector is composed of three layers of Al in a high-aluminum component layer 0.55 Ga 0.45 The N barrier layer and the metal electrode layer, and the other electrode is composed of only the metal electrode layer.
Optionally, the two side electrodes of the self-driven solar blind ultraviolet detector are interdigital electrodes, and the metal electrode layer on one side electrode and Al in the three high-aluminum component layers 0.4 Ga 0.6 The N active layer forms Schottky contact, the metal electrode layer on the other side electrode and Al in the three high-aluminum component layers 0.55 Ga 0.45 The N barrier layer forms a schottky contact.
Alternatively, the interdigital electrodes on two sides are symmetrically arranged, the interdigital width is 25+/-5 μm, the interdigital length is 500 μm, and the interval between adjacent interdigital is 10+/-5 μm.
Optionally, al in the three high-aluminum component layers 0.65 Ga 0.35 The thickness of the N layer is 1.5 mu m, al 0.4 Ga 0.6 The thickness of the N active layer is 300nm, al 0.55 Ga 0.45 The N barrier layer thickness was 50nm.
Optionally, the AlN buffer layer has a thickness of 2 μm.
Optionally, the material of the metal electrode layer is Ni/Au composite metal.
Optionally, the substrate layer material is sapphire.
The application provides a preparation method of a self-driven solar blind ultraviolet detector based on an asymmetric Schottky barrier, which comprises the following steps of:
step 1: growing an AlN buffer layer on the substrate layer;
step 2: to be undoped Al 0.65 Ga 0.35 N is deposited on the AlN buffer layer to form Al 0.65 Ga 0.35 An N buffer layer;
step 3: al (Al) 0.65 Ga 0.35 After the growth of the N layer, at the Al 0.65 Ga 0.35 Deposition of undoped Al on N buffer layer 0.4 Ga 0.6 N, form Al 0.4 Ga 0.6 An N active layer;
step 4: al (Al) 0.4 Ga 0.6 After the growth of the N layer, at the Al 0.4 Ga 0.6 Deposition of undoped Al on N active layer 0.55 Ga 0.45 N, form Al 0.55 Ga 0.45 N barrier layer simultaneously forming Al with polarization enhancement effect 0.55 Ga 0.45 N/Al 0.4 Ga 0.6 N/Al 0.65 Ga 0.35 An N heterostructure;
step 5: for the Al 0.55 Ga 0.45 Performing mesa isolation etching on the N barrier layer to form the asymmetric heterostructure;
step 6: and depositing a symmetrical interdigital metal electrode layer to form a Schottky electrode.
Optionally, the device epitaxial heterostructure grown on the substrate layer adopts a Metal Organic Chemical Vapor Deposition (MOCVD) method.
Optionally, the step 5 uses inductively coupled plasma and BCl 3 /Cl 2 And carrying out mesa etching by using gas.
The invention has the beneficial effects that:
(1) The AlGaN-based solar blind ultraviolet detector with the asymmetric heterostructure utilizes asymmetric polarization enhanced Al under one side electrode 0.55 Ga 0.45 N/Al 0.4 Ga 0.6 N/Al 0.65 Ga 0.35 The N heterostructure forms different barrier heights at two Schottky contact positions to induce energy band bending, so that an asymmetric energy band structure is formed, an internal potential difference exists between two electrodes, a built-in electric field is provided for photo-generated carriers, carrier separation and transportation are obviously promoted, photocurrent can be generated even if a device is not provided with bias voltage, self-driven detection is realized, and the defect of high energy consumption of the ultraviolet detector with the traditional MSM structure is overcome.
(2) The invention constructs three layers of high aluminum component layers and utilizes Al with polarization enhancement effect 0.55 Ga 0.45 N/Al 0.4 Ga 0.6 N/Al 0.65 Ga 0.55 The N epitaxial structure enhances the built-in electric field of the absorption layer by controlling polarization, and the interface charge is caused by the polarization effect in the heterostructure, so that a strong built-in electric field exists in the AlGaN absorption layer, thereby promoting the separation of photo-generated electron-hole pairs and further increasing the generation of photocurrent. Compared with the existing self-driven MSM ultraviolet photoelectric detector, the responsivity and the detection rate of the self-driven MSM ultraviolet photoelectric detector are greatly improved when the self-driven MSM ultraviolet photoelectric detector is in zero bias.
(3) The self-driven solar blind ultraviolet detector of the invention enables the screw dislocation density of the epitaxial structure to be lower and to be about 2.45 multiplied by 10 through the AlN/sapphire substrate 8 cm -2 The leakage channel is reduced, the device has ultra-low dark current, and the sensitivity of the device is improved.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
Fig. 1 is a schematic layer structure diagram of a self-driven solar blind ultraviolet detector based on an asymmetric schottky barrier.
FIG. 2 is a graph showing the I-V curve characteristics of the device of the present invention under-10 to 10V bias at room temperature without illumination and with illumination at 280 nm.
Fig. 3 is a graph of photocurrent response and spectral response of an ultraviolet detector of the present invention without a bias voltage (0V).
Fig. 4 is a structural comparison diagram of an ultraviolet detector a with an asymmetric MSM structure and a comparison device B of the present invention.
FIG. 5 is a graph of the spectral response of an asymmetric MSM structured UV detector of the present invention at 0V versus a control device symmetric MSM structured UV detector.
Detailed Description
For the purpose of making the objects, technical solutions and advantages of the present invention more apparent, the embodiments of the present invention will be described in further detail with reference to the accompanying drawings.
Embodiment one:
the present embodiment provides a self-driven solar blind ultraviolet detector based on an asymmetric schottky barrier, referring to fig. 1, the ultraviolet detector sequentially includes, from top to bottom: the substrate layer, the AlN buffer layer, the heterostructure layer and the metal electrode layer; wherein, heterostructure layer includes three high aluminium composition layers: al (Al) 0.65 Ga 0.35 N buffer layer, al 0.4 Ga 0.6 N active layer and Al 0.55 Ga 0.45 An N barrier layer; and one side electrode of the self-driven solar blind ultraviolet detector is composed of three layers of Al in high-aluminum component layers 0.55 Ga 0.45 The N barrier layer and the metal electrode layer, and the other electrode is composed of only the metal electrode layer.
The two side electrodes are interdigital electrodes, and the metal electrode layer on one side electrode and Al in the three high-aluminum component layers 0.4 Ga 0.6 N-activeThe layers form Schottky contact, and the metal electrode layer on the other side electrode and Al in the three high-aluminum component layers 0.55 Ga 0.45 The N barrier layer forms a schottky contact.
The application considers screw dislocation which is one of main defects in AlGaN materials, adopts an AlN/sapphire substrate, greatly reduces the screw dislocation density of an epitaxial structure, and improves the sensitivity of the device. In the AlN/sapphire substrate, the substrate layer is a sapphire substrate, the thickness of the AlN buffer layer is 2 mu m, and Al 0.65 Ga 0.35 The N buffer layer was not doped to a thickness of 1.5 μm, followed by 300nm thick Al 0.4 Ga 0.6 N active layer and 50nm thick Al 0.55 Ga 0.45 The N barrier layer forms a heterostructure. The material of the metal electrode layer is Ni/Au composite metal.
Using a cell with BCl 3 /Cl 2 Mesa etching is carried out by gas inductively coupled plasma to remove the residual Al 0.55 Ga 0.45 An N barrier layer of Al 0.55 Ga 0.45 N mesa, al of mesa structure 0.55 Ga 0.45 The N width was 25. Mu.m. Thus, the constitution is based on Al 0.55 Ga 0.45 N/Al 0.4 Ga 0.6 N/Al 0.65 Ga 0.55 An asymmetric heterostructure of N.
The interdigital electrodes on two sides of the ultraviolet detector are symmetrically arranged, the interdigital width is 25+/-5 mu m, the interdigital length is 500 mu m, and the distance between adjacent interdigital is 10+/-5 mu m.
Example two
The embodiment provides a preparation method of a self-driven solar blind ultraviolet detector based on an asymmetric schottky barrier, which is used for preparing the self-driven solar blind ultraviolet detector with the asymmetric heterostructure provided in the first embodiment, and the preparation method grows a device epitaxial heterostructure on a sapphire substrate through Metal Organic Chemical Vapor Deposition (MOCVD), and comprises the following steps:
step 1: growing an AlN buffer layer on the substrate layer;
step 2: to be undoped Al 0.65 Ga 0.35 The N layer is deposited on the AlN buffer layer;
step 3: al (Al) 0.65 Ga 0.35 After the growth of the N layer, at the Al 0.65 Ga 0.35 Deposition of undoped Al on the N layer 0.4 Ga 0.6 N, form Al 0.4 Ga 0.6 An N active layer;
step 4: al (Al) 0.4 Ga 0.6 After the growth of the N layer, at the Al 0.4 Ga 0.6 Deposition of undoped Al on the N layer 0.55 Ga 0.45 N, form Al 0.55 Ga 0.45 An N barrier layer forming Al 0.55 Ga 0.45 N/Al 0.4 Ga 0.6 N/Al 0.65 Ga 0.55 An N heterostructure;
step 5: using inductively coupled plasma with BCl 3 /Cl 2 Gas to Al 0.55 Ga 0.45 Performing mesa isolation etching on the N barrier layer to form asymmetric Al 0.55 Ga 0.45 N/Al 0.4 Ga 0.6 N/Al 0.65 Ga 0.55 An N heterostructure;
step 6: after mesa isolation etch, a standard Ni/Au (50/150 nm) schottky metal stack is deposited.
In order to further illustrate the beneficial effects that the self-driven solar blind ultraviolet detector with the asymmetric Schottky barrier can achieve, a series of experiments are carried out, and the experimental results are shown in figures 2-5.
FIG. 2 shows the I-V curves of the UV detector of the present invention under dark conditions and under illumination with 280nm monochromatic light, respectively. Dark current measured at room temperature is less than 1.0X10 at bias voltage ranging from-10V to 10V -11 A, at a bias voltage of 5V, can be as low as 1.8X10 -13 A. Photocurrent at bias voltage of 5V was 2.8x10 -9 A. Therefore, the test result shows that the self-driven solar blind ultraviolet detector device provided by the application has ideal light-dark current ratio of about 1.6X10 4 。
FIG. 3 shows the photocurrent response curve and the calibrated spectral response curve of the self-driven solar blind ultraviolet detector in the unbiased state. It can be seen that the device takes a photocurrent maximum at 280nm, is significantly cut off at 285nm at wavelength, and is compatible with Al 0.4 Ga 0.6 The forbidden bandwidth of the N absorption layer is consistent. In addition, at 0V, the responsivity of the self-driven solar blind ultraviolet detector device is 0.04A/W, and the detection rate is 3.1X10 12 Jones, achieves the self-driven function. This is due to the asymmetric heterostructure with polarization enhancement effect forming an asymmetric MSM device, whereby the different barrier heights provide an asymmetric energy band and enhance Al due to its polarization effect 0.4 Ga 0.6 Built-in electric field of the N active layer.
To highlight the application of the self-driven solar blind ultraviolet detector, the metal electrode layer on one side electrode and the Al in three high-aluminum component layers are provided 0.4 Ga 0.6 The N active layer forms Schottky contact, the metal electrode layer on the other side electrode and Al in the three high-aluminum component layers 0.55 Ga 0.45 The N barrier layer forms the beneficial effect brought by schottky contact, and the embodiment also prepares a symmetrical structure device B, and compares the self-driven solar blind ultraviolet detector provided by the application, and the symmetrical structure device B is different from the device of the application in that electrodes on two sides of the symmetrical structure device B are both identical to Al 0.55 Ga 0.45 The N barrier layer forms a schottky contact, see fig. 4.
Fig. 5 shows the comparison result of the light response curve of the self-driven solar blind ultraviolet detector device a and the symmetrical structure device B provided by the application at 0V, and the comparison result can obviously show that the response spectrum of the self-driven solar blind ultraviolet detector device a provided by the application has obvious response broad peaks at 250-280 nm, namely obvious response broad peaks to solar blind ultraviolet rays, but the light response curve of the device B at 0V has no obvious response peak.
In summary, the ultraviolet detector of the invention can realize self-driving characteristics, low dark current and higher zero bias responsivity. Therefore, the structural design makes up the defect of high power consumption of the horizontal symmetrical MSM structural device, and the responsiveness is greatly improved.
Some steps in the embodiments of the present invention may be implemented by using software, and the corresponding software program may be stored in a readable storage medium, such as an optical disc or a hard disk.
The foregoing description of the preferred embodiments of the invention is not intended to limit the invention to the precise form disclosed, and any such modifications, equivalents, and alternatives falling within the spirit and scope of the invention are intended to be included within the scope of the invention.
Claims (10)
1. The utility model provides a self-driven solar blind ultraviolet detector based on asymmetric schottky barrier which characterized in that, self-driven solar blind ultraviolet detector from down includes in proper order: the substrate layer, the AlN buffer layer, the heterostructure layer and the metal electrode layer; wherein, heterostructure layer includes three high aluminium component layers: al (Al) 0.65 Ga 0.35 N buffer layer, al 0.4 Ga 0.6 N active layer and Al 0.55 Ga 0.45 An N barrier layer; and one side electrode of the self-driven solar blind ultraviolet detector is composed of three layers of Al in a high-aluminum component layer 0.55 Ga 0.45 The N barrier layer and the metal electrode layer, and the other electrode is composed of only the metal electrode layer.
2. The self-driven solar blind ultraviolet detector according to claim 1, wherein the two side electrodes of the self-driven solar blind ultraviolet detector are interdigital electrodes, and the metal electrode layer on one side electrode and the Al in the three high-aluminum component layers 0.4 Ga 0.6 The N active layer forms Schottky contact, the metal electrode layer on the other side electrode and Al in the three high-aluminum component layers 0.55 Ga 0.45 The N barrier layer forms a schottky contact.
3. The self-driven solar blind ultraviolet detector according to claim 2, wherein the interdigital electrodes on both sides are symmetrically arranged, the interdigital width is 25±5 μm, the interdigital length is 500 μm, and the interval between adjacent interdigital is 10±5 μm.
4. The self-driven solar blind ultraviolet detector according to claim 1, wherein Al in the three high-alumina component layers 0.65 Ga 0.35 The thickness of the N layer is 1.5 mu m, al 0.4 Ga 0.6 The N active layer thickness is 300nm,Al 0.55 Ga 0.45 the N barrier layer thickness was 50nm.
5. The self-driven solar blind ultraviolet detector according to claim 1, wherein the AlN buffer layer has a thickness of 2 μm.
6. The self-driven solar blind ultraviolet detector according to claim 1, wherein the material of the metal electrode layer is Ni/Au complex metal.
7. The self-driven solar blind ultraviolet detector of claim 1 wherein the substrate layer material is sapphire.
8. The preparation method of the self-driven solar blind ultraviolet detector based on the asymmetric Schottky barrier is characterized by comprising the following steps of:
step 1: growing an AlN buffer layer on the substrate layer;
step 2: to be undoped Al 0.65 Ga 0.35 N is deposited on the AlN buffer layer to form Al 0.65 Ga 0.35 An N buffer layer;
step 3: al (Al) 0.65 Ga 0.35 After the growth of the N layer, at the Al 0.65 Ga 0.35 Deposition of undoped Al on N buffer layer 0.4 Ga 0.6 N, form Al 0.4 Ga 0.6 An N active layer;
step 4: al (Al) 0.4 Ga 0.6 After the growth of the N layer, at the Al 0.4 Ga 0.6 Deposition of undoped Al on N active layer 0.55 Ga 0.45 N, form Al 0.55 Ga 0.45 N barrier layer simultaneously forming Al with polarization enhancement effect 0.55 Ga 0.45 N/Al 0.4 Ga 0.6 N/Al 0.65 Ga 0.35 An N heterostructure;
step 5: for the Al 0.55 Ga 0.45 The N barrier layer is subjected to mesa isolation etching to formForming the asymmetric heterostructure;
step 6: and depositing a symmetrical interdigital metal electrode layer to form a Schottky electrode.
9. The method of claim 8, wherein growing the device epitaxial heterostructure on the substrate layer employs a metal organic chemical vapor deposition MOCVD process.
10. The method of claim 8, wherein said step 5 employs inductively coupled plasma with BCl 3 /Cl 2 And carrying out mesa etching by using gas.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311653005.XA CN117673188A (en) | 2023-12-05 | 2023-12-05 | Self-driven solar blind ultraviolet detector based on asymmetric Schottky barrier |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311653005.XA CN117673188A (en) | 2023-12-05 | 2023-12-05 | Self-driven solar blind ultraviolet detector based on asymmetric Schottky barrier |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117673188A true CN117673188A (en) | 2024-03-08 |
Family
ID=90072781
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311653005.XA Pending CN117673188A (en) | 2023-12-05 | 2023-12-05 | Self-driven solar blind ultraviolet detector based on asymmetric Schottky barrier |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117673188A (en) |
-
2023
- 2023-12-05 CN CN202311653005.XA patent/CN117673188A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US9082920B2 (en) | Back contact solar cell and manufacturing method thereof | |
| CN107863413B (en) | A kind of AlGaN base day blind ultraviolet snowslide heterojunction phototransistor detector and preparation method thereof | |
| CN108305911B (en) | It absorbs, III group-III nitride semiconductor avalanche photodetector of dynode layer separated structure | |
| CN102214705B (en) | AlGan polarized ultraviolet photoelectric detector and manufacturing method thereof | |
| CN109494275B (en) | AlGaN-based solar blind ultraviolet phototransistor detector and manufacturing method thereof | |
| CN110660882B (en) | Grid-controlled PIN structure GaN ultraviolet detector and preparation method thereof | |
| US11522091B2 (en) | Solar cell | |
| CN109935655B (en) | AlGaN/SiC bicolor ultraviolet detector | |
| CN111081792B (en) | Back-illuminated ultraviolet-infrared double-color photoelectric detector and preparation method thereof | |
| CN109980040A (en) | A kind of gallium oxide MIS structure ultraviolet detector | |
| US8455756B2 (en) | High efficiency solar cell using IIIB material transition layers | |
| CN111403505A (en) | Bipolar visible light detector and preparation method thereof | |
| CN114267747B (en) | Ga with metal gate structure 2 O 3 AlGaN/GaN solar blind ultraviolet detector and preparation method thereof | |
| CN107393983B (en) | Nitride quantum well infrared detector containing polarization regulating layer and preparation method thereof | |
| CN106684203A (en) | GaN (Gallium Nitrogen) avalanche photodiode assembly and manufacturing method thereof | |
| Mosca et al. | Multilayer (Al, Ga) N structures for solar-blind detection | |
| CN116799092A (en) | Solar blind ultraviolet detector based on gallium oxide base and preparation method thereof | |
| CN116705876A (en) | Mixed-dimension heterojunction type photoelectric detector and preparation method thereof | |
| CN114678439B (en) | 2DEG ultraviolet detector with symmetrical interdigital structure and preparation method thereof | |
| CN117673188A (en) | Self-driven solar blind ultraviolet detector based on asymmetric Schottky barrier | |
| CN112018210B (en) | Polarization-enhanced narrow-band AlGaNp-i-n type ultraviolet detector and preparation method thereof | |
| CN209675319U (en) | A kind of gallium oxide MIS structure ultraviolet detector | |
| Mosca et al. | Effects of the buffer layers on the performance of (Al, Ga) N ultraviolet photodetectors | |
| CN117293199A (en) | Self-driven GaN-based ultraviolet detector with asymmetric interdigital structure and preparation method thereof | |
| CN115101603B (en) | Photodetector |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |