CN111490112B - Novel silicon carbide Schottky junction extreme deep ultraviolet detector and preparation method thereof - Google Patents
Novel silicon carbide Schottky junction extreme deep ultraviolet detector and preparation method thereof Download PDFInfo
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Abstract
The invention discloses a novel silicon carbide Schottky junction extreme-deep ultraviolet detector and a preparation method thereof. The method effectively avoids the strong absorption of the generated ultra-deep ultraviolet photon in the surface highly-doped p-type layer when the conventional ultraviolet detector with the traditional p-i-n structure is applied to the ultra-deep ultraviolet band detection, and effectively improves the quantum efficiency of the ultra-deep ultraviolet band detector; furthermore, the Schottky electrode structure is optimized to be an incomplete filling structure, so that the reflection and absorption of the ultra-deep ultraviolet photon on the surface of the metal electrode are effectively reduced, and the quantum efficiency of the Schottky junction detector in the ultra-deep ultraviolet band, particularly the vacuum ultraviolet band, is further improved.
Description
Technical Field
The invention relates to a novel silicon carbide Schottky junction extreme-deep ultraviolet detector and a preparation method thereof, belonging to the technical field of photoelectric detection of semiconductor devices.
Background
The ultra-deep ultraviolet detection technology is a novel photoelectric detection technology which is newly emerged in recent years, and has very wide application prospects in the fields of scientific research and industrial production, such as plasma physics, satellite space environment monitoring, integrated circuit 7nm and below process procedure photoetching and the like. The extreme deep ultraviolet detector is mainly used for detecting short-wavelength and high-energy ultraviolet light with the wavelength range of 10-200nm, and because the ultraviolet light in the wave band has weak signals and relatively high photon energy in an application scene, the extreme deep ultraviolet detector is required to have good noise characteristics and radiation resistance, and the requirements are obviously difficult to achieve by a silicon (Si) based detector.
Compared with the traditional Si material, the silicon carbide (SiC) material which is a typical representative of the wide-bandgap semiconductor material has the characteristics of large forbidden band width, low intrinsic carrier concentration, high critical displacement energy and good chemical stability, and has significant material performance advantages in the aspect of preparing a photoelectric detector working in an ultraviolet band: the room-temperature forbidden band width of the 4H-SiC is 3.26eV, the corresponding cut-off wavelength is 380nm, the visible light blind characteristic is realized, a complex and expensive optical filter does not need to be additionally arranged, and the manufacturing cost and the process complexity of the ultraviolet detector are effectively reduced; the forbidden bandwidth which is three times that of the Si material greatly reduces the leakage current of the SiC-based ultraviolet detector, thereby effectively improving the detection capability of weak extreme-deep ultraviolet signals; the critical displacement energy of the SiC material is as high as 22eV, and for an extreme deep ultraviolet detector working in a strong radiation environment, the SiC-based device has better radiation resistance and longer device service life, so that the stability of the device can be effectively improved, and the maintenance cost of equipment can be greatly reduced.
At present, the SiC-based detector used for conventional ultraviolet band detection is mainly of a p-i-n structure, and because the transmission depth of extreme deep ultraviolet photons in semiconductor materials such as SiC and the like is extremely shallow, a large number of incident photons are absorbed by a p-type layer on the surface, so that the quantum efficiency of the traditional ultraviolet detector is extremely low when the traditional ultraviolet detector is used for detecting the extreme deep ultraviolet band. How to effectively reduce the loss of extreme deep ultraviolet photons and improve the detection efficiency of devices is one of the key scientific problems faced by the preparation of SiC base deep ultraviolet detectors.
Disclosure of Invention
The invention provides a novel silicon carbide Schottky junction extreme-deep ultraviolet detector and a preparation method thereof, and aims to solve the problems that the transmission efficiency of incident photons of the detector in an extreme-deep ultraviolet band, particularly a vacuum ultraviolet band (100-200nm), is low and the detection efficiency of a device is low.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows:
the utility model provides a novel carborundum schottky junction extreme depth ultraviolet detector, includes that from the bottom up meets in proper order n type ohmic contact electrode, substrate, n type low epitaxial layer of mixing and n type schottky contact electrode, n type schottky contact electrode is equipped with metal conductive electrode along the periphery, and metal conductive electrode is equipped with the passivation layer along the periphery.
The novel silicon carbide Schottky junction extreme ultraviolet detector is different from a p-i-n structure adopted by a conventional ultraviolet band detector, adopts a Schottky structure with a surface junction, effectively avoids the loss of extreme deep ultraviolet photons in a highly doped p-type layer, enables the extreme deep ultraviolet photons to enter an active absorption region on the surface of a device from a semitransparent Schottky metal electrode, and further improves the detection efficiency of the device in the extreme deep ultraviolet band, particularly the vacuum ultraviolet band.
The n-type ohmic contact electrode is connected with a negative voltage in the test; the n-type low-doped epitaxial layer is a structural layer for receiving incident photons, and the low doping concentration enables the device to obtain a wider depletion region under low bias voltage and obtain lower leakage current under high bias voltage; the n-type Schottky contact electrode is used for forming a Schottky contact; the metal conductive electrode can effectively improve the current transmission and charge collection capability of the device, and is used for packaging a routing and grounding electrode in testing; and the passivation layer is used for device isolation.
In order to further improve the quantum efficiency, the n-type Schottky contact electrode is of an incomplete filling structure, and the filling factor is 10-80%; preferably, the fill factor is 50%. Schottky contact is formed between the incompletely filled n-type Schottky contact electrode and the n-type low-doped epitaxial layer, electron-hole pairs excited by incident ultra-deep ultraviolet photons are separated under the combined action of an electric field and a drift electric field in a Schottky junction to form photoresponse current, so that the detection of the ultra-deep ultraviolet photons is realized, and the incomplete filling design of the Schottky contact electrode can effectively avoid the influence of a large amount of loss and photoelectric effect of the incident photons on the metal electrode. More preferably, the n-type schottky contact electrode is in the form of a bar, a mesh, or a ring. When the n-type Schottky contact electrode is in a grid shape, the width of the strip electrode in the grid-shaped electrode is less than 5 micrometers, and the interval between two adjacent strip electrodes is less than 5 micrometers.
The principle of the scheme is as follows: the deep ultraviolet photons of the emitter are absorbed by the active region of the device to generate electron-hole pairs, the photo-generated electron-hole pairs are separated under the combined action of an electric field built in the Schottky junction and a drift electric field, and the electrons and the holes are respectively collected by the cathode and the anode of the device to form photocurrent; for a bar-shaped and semi-transparent n-type Schottky contact electrode, under the action of reverse bias voltage, a depletion region below the bar-shaped and semi-transparent n-type Schottky contact electrode expands like electrodeless regions at two sides, and finally pinch-off occurs, and in fact, under the condition of zero bias voltage, the depletion region has already undergone a considerable degree of lateral expansion; the design of the incomplete filling electrode structure can effectively reduce the reflection and absorption of incident photons on the surface of the metal electrode, and greatly improve the detection efficiency of the device.
In order to reduce the leakage of the device and improve the stability of the device, an oxide film is deposited in the electrode-free region, for example, when the n-type Schottky contact electrode is in a grid shape, the adjacent two strip-shaped electrodes are separated by the ultrathin oxide film. Preferably, the material of the oxide film is SiO2And the thickness is less than 5 nm.
In order to further improve the performance of the device, the substrate is made of SiC; the material of the n-type low-doped epitaxial layer is SiC. Compared with an AlN cap layer and the like, the n-type SiC low-doped epitaxial layer has lower defect density and higher crystal quality, so that the corresponding SiC device has lower leakage current and higher quantum efficiency, the AlN cap layer structure device is specific to the wavelength of more than 200nm, and the device is mainly specific to the ultra-deep ultraviolet band with the wavelength of less than 200 nm. More preferably, the doping concentration of the substrate is 1 × 1018cm-3～1×1020cm-3More preferably 1X 1019cm-3(ii) a The doping concentration of the n-type low-doped epitaxial layer is 1 multiplied by 1014cm-3～1×1015cm-3More preferably 3X 1014cm-3. The thickness of the n-type low-doped epitaxial layer is 3-5 μm.
In order to ensure the comprehensive performance of the device, the material of the passivation layer is SiO2、Si3N4、Al2O3One or a mixture of more than two of materials such as AlN and the like in any proportion; the n-type ohmic contact electrode is made of one or a mixture of more than two of materials such as nickel, titanium, aluminum, gold and the like in any proportion, preferably a nickel layer, a titanium layer, an aluminum layer and a gold layer which are sequentially connected from bottom to top, wherein the thickness of the nickel layer is 30-40 nm, the thickness of the titanium layer is 40-60 nm, the thickness of the aluminum layer is 90-110 nm, and the thickness of the gold layer is 90-110 nm; the n-type Schottky contact electrode is made of nickel,One of high-work-function metal materials such as chromium, platinum and palladium is 3-10 nm thick; the metal conductive electrode comprises a Schottky metal material layer and a conductive metal material layer which are sequentially connected from bottom to top, the total thickness of the metal conductive electrode is at least 1 mu m, preferably, the Schottky metal material layer is composed of the Schottky metal material layer, a titanium layer and a gold layer, the thickness of the Schottky metal material layer is 150-250 nm, the thickness of the titanium layer is 250-350 nm, and the thickness of the gold layer is 450-550 nm; the metal conductive electrode comprises a Pad area used for lead bonding and a line area used for conducting, wherein the side length of the Pad area is 90-110 mu m, and the width of the line area is 25-35 mu m, so that the packaging of the device is facilitated, and the conductivity and the effective area can be better considered.
The preparation method of the novel silicon carbide Schottky junction extreme deep ultraviolet detector comprises the following steps of sequentially connecting:
1) epitaxially growing an n-type low-doped epitaxial layer on the upper surface of the substrate; preferably, an n-type low-doped epitaxial layer is epitaxially grown on the upper surface of the substrate by adopting a high-temperature Chemical Vapor Deposition (CVD) mode;
2) depositing a passivation layer on the n-type low-doped epitaxial layer, and then carrying out high-temperature densification to reduce a leakage path inside the passivation layer, further realizing device isolation and reducing device leakage current; preferably, a passivation layer is deposited on the N-type low-doped epitaxial layer by adopting a Plasma Enhanced Chemical Vapor Deposition (PECVD) method, and then the N-type low-doped epitaxial layer is placed in nitrogen (N)2) Performing high-temperature densification in the atmosphere;
3) spin-coating photoresist on the passivation layer, defining an optical window through exposure and development, etching off the passivation layer in the optical window area, and then carrying out dry-oxygen oxidation to form a compact ultrathin oxide film in the optical window area on the n-type low-doped epitaxial layer; preferably, the in-situ oxidation adopts dry oxygen oxidation or wet oxygen oxidation; further preferably dry oxygen oxidation; the growth rate is strictly controlled, and a compact oxide film is formed. By forming the ultrathin oxide film, the surface state/interface state density of the device can be effectively reduced, the surface of the exposed SiC epitaxial layer is protected, and the transmission efficiency of deep ultraviolet photons entering an emitter can be ensured;
4) removing the oxide film on the lower surface of the substrate by wet etching, depositing an n-type ohmic contact electrode on the lower surface of the substrate in a PVD (physical vapor deposition) mode, and then annealing at high temperature to form ohmic contact;
5) spin-coating photoresist on the surface of the epitaxial wafer, corroding the ultrathin oxide film in the optical window area by a wet method according to a photoetching pattern obtained by exposure and development, depositing an n-type Schottky contact electrode in the optical window area, and then carrying out low-temperature annealing to form Schottky contact; preferably, an n-type Schottky contact electrode is deposited in the optical window area by adopting a PVD mode; the temperature of the preferred low-temperature annealing process is lower than 400 ℃, so that the surface of the Schottky electrode is prevented from being roughened, the state density of a Schottky contact interface is reduced, and the height of a Schottky contact barrier is increased;
6) and depositing a metal conductive electrode at the edge of the n-type Schottky contact electrode, and then carrying out secondary low-temperature annealing to eliminate the damage in the device preparation process and finish the preparation of the novel silicon carbide Schottky junction extreme ultraviolet detector. Preferably, the metal conductive electrode is deposited by PVD.
In order to prepare the incompletely filled electrode, step 5) is to etch off the ultrathin oxide film in the optical window area at intervals according to the photoetching pattern obtained by exposure and development, so that the ultrathin oxide film is reserved in part of the area on the optical window area, the rest area is made of exposed SiC material, the n-type Schottky contact electrode is deposited in the part where the ultrathin oxide film is etched off in the optical window area, and after stripping, low-temperature annealing is carried out, so that the incompletely filled n-type Schottky contact electrode is formed.
The prior art is referred to in the art for techniques not mentioned in the present invention.
The novel silicon carbide Schottky junction extreme-deep ultraviolet detector effectively avoids strong absorption of extreme-deep ultraviolet photons in a surface highly-doped p-type layer when a conventional ultraviolet detector with a conventional p-i-n structure is applied to detection of an extreme-deep ultraviolet band, and effectively improves the quantum efficiency of the extreme-deep ultraviolet band detector; furthermore, the Schottky electrode structure is optimized to be an incomplete filling structure, so that the reflection and absorption of the ultra-deep ultraviolet photon on the surface of the metal electrode are effectively reduced, and the quantum efficiency of the Schottky junction detector in the ultra-deep ultraviolet band, particularly the vacuum ultraviolet band, is further improved.
Drawings
FIG. 1 is a flow chart of a preparation method of the SiC-based Schottky junction extreme ultraviolet detector in the invention;
fig. 2 is a schematic structural view of a SiC-based schottky junction euv detector of a grid-like electrode in embodiment 1 of the present invention;
fig. 3(1) and (2) are schematic diagrams of unequal proportion electric field distribution of the SiC-based schottky junction euv detector of the grid strip electrode in embodiment 1 of the present invention under reverse bias voltages of 0V and-15V, respectively;
fig. 4 is a current-voltage characteristic curve of the novel SiC-based schottky junction euv detector of the grid electrode in embodiment 1 of the present invention.
Fig. 5 is a quantum efficiency curve of the novel SiC-based schottky junction euv detector of the gate strip electrode, the SiC-based schottky junction euv detector of the fully-filled electrode, and the conventional p-i-n structure euv detector in embodiment 1 of the present invention under a reverse bias voltage of-15V and in a wavelength range of 43.5-103.5 nm.
Fig. 6 is a quantum efficiency curve of the novel SiC-based schottky junction euv detector of the gate strip electrode and the SiC-based schottky junction euv detector of the fully-filled electrode in embodiment 1 of the present invention in the wavelength range of 10-140nm under reverse bias voltages of 0V and-15V, respectively.
In the figure, 1 is an n-type ohmic contact electrode; 2 is an n-type SiC substrate; 3 is an n-type SiC low-doped epitaxial layer; 4 is SiO2A passivation layer; 5 is a metal conductive electrode; 6 is ultrathin SiO2An oxide layer; and 7, a grid-shaped semitransparent metal electrode.
Detailed Description
In order to better understand the present invention, the following examples are further provided to illustrate the present invention, but the present invention is not limited to the following examples.
Example 1
As shown in figure 2, the grid-shaped electrode SiC-based Schottky junction extreme ultraviolet detector comprises an n-type ohmic contact electrode 1, an n-type SiC substrate 2, an n-type low-doped epitaxial layer 3 and a grid-shaped semi-permeable epitaxial layer which are sequentially connected from bottom to topA transparent metal electrode 7, a metal conductive electrode 5 arranged on the grid-shaped semitransparent metal electrode 7 along the periphery, and SiO arranged on the metal conductive electrode 5 along the periphery2A passivation layer 4; the grid-shaped semitransparent metal electrode 7 is in a grid shape consisting of strip-shaped electrodes, the width of each strip-shaped electrode is 5 micrometers, the interval between every two adjacent strip-shaped electrodes is 5 micrometers, and ultrathin SiO is used between every two adjacent strip-shaped electrodes2The oxide layers 6 are spaced apart.
As shown in fig. 1, the device preparation process is as follows:
step 101, doping concentration is 1 × 1019cm-3On a SiC substrate 2 with a thickness of 350 μm, an n-type low-doped epitaxial layer 3 with a thickness of 4 μm is epitaxially grown by high-temperature CVD, the material is SiC, and the doping concentration is 3 × 1014cm-3Therefore, the device can obtain a wider depletion region under a low bias voltage and obtain lower leakage current under a high bias voltage.
102, depositing SiO with the thickness of 500nm on the surface of the n-type low-doped epitaxial layer 3 by adopting a PECVD method2Passivation layer 4, which is then placed on N2And performing high-temperature densification in the atmosphere to reduce a leakage path inside the passivation layer, further realize device isolation and reduce device leakage current.
Step 103, in SiO2Photoresist is spin-coated on the passivation layer 4, an optical window is defined through exposure and development, the epitaxial wafer is immersed in buffer oxide etching liquid (BOE) for wet etching, and under the protection action of the photoresist, SiO (silicon dioxide) at the position of the optical window2The passivation layer is corroded to expose the surface of the exposed SiC low-doped epitaxial layer; then placing the SiC epitaxial wafer in O2Dry oxygen oxidation is carried out in the atmosphere, and a compact ultrathin oxide film (ultrathin SiO) with the thickness of about 3nm is formed in the optical window area on the n-type low-doped epitaxial layer 32Oxide layer 6), the material used is SiO2；
104, spin-coating photoresist on the front surface of the epitaxial wafer, further immersing the epitaxial wafer into BOE, and protecting the SiO on the front surface2Passivation layer 4 and SiO2The oxide layer 6 is preceded by the removal of the dry oxide layer unintentionally grown on the backside of the substrate 2 in step 103; further cleaning by PVDAnd sequentially depositing metal Ni/Ti/Al/Au with the thickness of about 35/50/100/100nm on the back of the substrate 2, and putting the epitaxial wafer subjected to metal deposition into an annealing furnace for high-temperature annealing so as to form the n-type ohmic contact electrode 1 on the back of the substrate 2.
And 105, spin-coating photoresist on the front surface of the epitaxial wafer, forming a grid bar pattern in an optical window region after photoetching development, immersing the epitaxial wafer into BOE, corroding to remove the ultrathin oxide film without covering part of the photoresist, depositing a semitransparent Ni metal film with the thickness of 5nm in the window region through PVD (physical vapor deposition), stripping to obtain a grid bar-shaped electrode, putting the epitaxial wafer into an annealing furnace, annealing at low temperature (lower than 400 ℃) to form Schottky contact, and thus obtaining the grid bar-shaped semitransparent metal electrode 7.
And 106, spin-coating photoresist on the front surface of the epitaxial wafer, forming a photoetching pattern of a metal conductive electrode in the edge area of the grid-strip-shaped semitransparent metal electrode 7 after photoetching development, further depositing metal Ni// Ti/Au in sequence through PVD, wherein the thickness of the metal Ni// Ti/Au is about 200/300/500nm in sequence, forming the metal conductive electrode 5 after stripping, wherein the width of the metal conductive electrode is 30 mu m, the side length of the Pad of the metal conductive electrode is 100 mu m, and further performing secondary low-temperature annealing (lower than 250 ℃) so as to repair a damaged Schottky interface in the electrode preparation process, further improve the stability of the device and reduce the leakage current of the device.
And 107, splitting the wafer, dividing the epitaxial wafer into single devices, routing and packaging the finished devices on a TO tube seat, carrying out further electro-optical test, connecting the n-type ohmic contact electrode 1 with a negative voltage in the test, and connecting the metal conductive electrode with a grounding electrode.
Compared with the conventional ultraviolet detector with the conventional p-i-n structure, the grid-strip-shaped electrode SiC-based Schottky junction extreme-deep ultraviolet detector provided by the embodiment 1 can effectively reduce the loss of emitter-in deep ultraviolet photons on the surface layer of the device, greatly improves the detection performance of the device, can effectively avoid the reflection and absorption of incident photons on the surface of the metal electrode, and further improves the quantum efficiency of the Schottky junction detector in the extreme-deep ultraviolet band, especially the vacuum ultraviolet band.
Fig. 3(1) and (2) are schematic diagrams illustrating unequal proportion electric field distribution of the SiC-based schottky junction euv detector of the grid strip electrode in embodiment 1 of the present invention under reverse bias voltages of 0V and-15V, respectively. As can be seen from fig. 3, in the incompletely filled electrode device represented by the gate-stripe electrode device provided in embodiment 1, the depletion region of the electrode region expands laterally under the combined action of the schottky contact potential and the reverse bias voltage, so as to increase the active region area of the device. As shown in fig. 3, the electron-hole pairs excited by the incident photons are separated under the action of the electric field built in the schottky junction and the drift electric field, and the photo-generated electrons and holes are respectively collected by the cathode and the anode of the device and form photocurrent, thereby realizing the calibration of the incident light intensity.
As can be seen from fig. 4, the grid-like electrode device provided in example 1 has excellent noise characteristics, and the leakage current of the device provided in example 1 is in the order of pA at room temperature and a reverse bias voltage of-20V.
Fig. 5 is a quantum efficiency curve of the novel SiC-based schottky junction euv detector of the gate strip electrode, the SiC-based schottky junction euv detector of the fully-filled electrode, and the conventional p-i-n structure euv detector in embodiment 1 of the present invention under a reverse bias voltage of-15V and in a wavelength range of 43.5-103.5 nm. As can be seen from fig. 5, in the above wavelength band where the photon transmission depth is about 10 to 33nm, the quantum efficiency of the device provided by embodiment 1 of the present invention is much higher than that of the conventional p-i-n structure ultraviolet detector, which verifies that the application of the incompletely filled schottky structure can effectively reduce the loss of the emitter deep ultraviolet photons in the non-active absorption region of the surface layer of the device.
Fig. 6 shows quantum efficiency curves of the device provided in example 1 and the fully-filled schottky junction device in the wavelength ranges of 10-140nm at reverse bias voltages of 0V and-15V, respectively, and it can be seen from fig. 6 that the quantum efficiency of the device in example 1 is significantly higher than that of the fully-filled schottky junction device, which indicates that the optimization of the schottky electrode structure into incomplete filling electrode structures such as a gate strip, a grid, and a ring can reduce the reflection and absorption of incident ultraviolet photons on the surface of the metal electrode, and effectively improve the quantum efficiency of the device in the ultra-deep ultraviolet band, especially in the vacuum ultraviolet band.
Claims (8)
1. A novel silicon carbide Schottky junction extreme ultraviolet detector is characterized in that: the n-type Schottky contact electrode is provided with a metal conductive electrode along the periphery, and the metal conductive electrode is provided with a passivation layer along the periphery;
the n-type Schottky contact electrode is of an incomplete filling structure and is in a grid bar shape, a grid shape or a ring shape; the thickness of the n-type Schottky contact electrode is 3-10 nm;
the preparation method of the novel silicon carbide Schottky junction extreme deep ultraviolet detector comprises the following steps of sequentially connecting:
1) epitaxially growing an n-type low-doped epitaxial layer on the upper surface of the substrate;
2) depositing a passivation layer on the n-type low-doped epitaxial layer, and then carrying out high-temperature densification;
3) etching off the passivation layer of the optical window area by a wet method, and then carrying out in-situ oxidation to form a compact oxidation film in the optical window area on the n-type low-doped epitaxial layer;
4) removing the oxide film on the lower surface of the substrate by wet etching, depositing an n-type ohmic contact electrode on the lower surface of the substrate, and then performing high-temperature annealing to form ohmic contact;
5) corroding the ultrathin oxide film in the optical window area by a wet method, depositing an n-type Schottky contact electrode in the optical window area, and then annealing at a low temperature to form Schottky contact, wherein the temperature of the low-temperature annealing is lower than 400 ℃;
6) and depositing a metal conductive electrode at the edge of the n-type Schottky contact electrode, then carrying out secondary low-temperature annealing, repairing the damage of the device, and completing the preparation of the novel silicon carbide Schottky junction extreme ultraviolet detector.
2. The novel silicon carbide schottky junction euv detector of claim 1, wherein: the filling factor of the metal electrode in the grid-shaped, grid-shaped or annular electrode is 10-80%.
3. A novel silicon carbide schottky junction euv detector as claimed in claim 1 or 2, wherein: the electrodeless filling area is deposited with an ultrathin oxide film.
4. The novel silicon carbide schottky junction euv detector of claim 3, wherein: the material of the oxide film is SiO2And the thickness is less than 5 nm.
5. A novel silicon carbide schottky junction euv detector as claimed in claim 1 or 2, wherein: the substrate is made of SiC and has a doping concentration of 1 × 1018cm-3～1×1020cm-3(ii) a The n-type low-doped epitaxial layer is made of SiC, and the doping concentration of the n-type low-doped epitaxial layer is less than 1 x 1015cm-3(ii) a The thickness of the n-type low-doped epitaxial layer is more than 1 mu m.
6. A novel silicon carbide schottky junction euv detector as claimed in claim 1 or 2, wherein: the passivation layer is made of SiO2、Si3N4、Al2O3Or AlN; the material of the n-type ohmic contact electrode is at least one of nickel, titanium, aluminum or gold; the n-type Schottky contact electrode is made of one of nickel, chromium, platinum or palladium; the metal conductive electrode comprises a Schottky metal material layer and a conductive metal material layer which are sequentially connected from bottom to top, and the total thickness of the metal conductive electrode is at least 1 mu m; the metal conductive electrode includes Pad regions for wire bonding and line regions for conduction.
7. The novel silicon carbide schottky junction euv detector of claim 6, wherein: the n-type ohmic contact electrode comprises a nickel layer, a titanium layer, an aluminum layer and a gold layer which are sequentially connected from bottom to top, wherein the thickness of the nickel layer is 30-40 nm, the thickness of the titanium layer is 40-60 nm, the thickness of the aluminum layer is 90-110 nm, and the thickness of the gold layer is 90-110 nm; in the metal conductive electrode, the thickness of the Schottky metal material layer is 150-250 nm, the thickness of the titanium layer is 250-350 nm, the thickness of the gold layer is 450-550 nm, the side length of the Pad area is 90-110 microns, and the width of the line area is 25-35 microns.
8. A novel silicon carbide schottky junction euv detector as claimed in claim 1 or 2, wherein: and step 5) etching the ultrathin oxide film in the optical window area at intervals according to the photoetching pattern obtained by exposure and development, keeping the ultrathin oxide film in part of the area on the optical window area, enabling the rest area to be a naked SiC material, depositing the n-type Schottky contact electrode in the part where the ultrathin oxide film is etched in the optical window area, stripping, and annealing at low temperature to form the incompletely filled n-type Schottky contact electrode.
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| CN113921589A (en) * | 2021-09-02 | 2022-01-11 | 西安电子科技大学 | Gallium oxide-based sunlight blind area detector based on zero-grid bias |
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| JPS57126179A (en) * | 1981-01-29 | 1982-08-05 | Mitsubishi Electric Corp | Schottky type photo detector |
| CN102361046A (en) * | 2011-09-30 | 2012-02-22 | 天津大学 | Solar blind ultraviolet detector with AlGaN-based MSM (Metal-Semiconductor-Metal) structure and manufacturing method thereof |
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| CN104701408A (en) * | 2013-12-09 | 2015-06-10 | 青岛平度市旧店金矿 | MSM structure 4H-SiC ultraviolet photodetector manufacture process |
| CN105047749B (en) * | 2015-08-25 | 2017-05-24 | 镇江镓芯光电科技有限公司 | SiC Schottky ultraviolet detector with passivation layer having filtering function |
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| CN102361046A (en) * | 2011-09-30 | 2012-02-22 | 天津大学 | Solar blind ultraviolet detector with AlGaN-based MSM (Metal-Semiconductor-Metal) structure and manufacturing method thereof |
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