Diamond detector and manufacturing method thereof

Abstract

The present invention discloses a diamond detector and a manufacturing method thereof, which belongs to the field of radiation detection technology and can solve the problems of low sensitivity, poor radiation resistance and short service life of existing radiation detectors. The detector comprises: a mounting circuit board, on which a first pad, a second pad, a third pad and a circuit structure are arranged; a detection element, which comprises a diamond sheet, and a first electrode and a second electrode arranged on opposite surfaces of the diamond sheet; the first electrode is welded on the first pad, and the second electrode is connected to the second pad; a fixed cover plate, which is arranged on a side of the mounting circuit board close to the detection element; a radiation window is opened on the fixed cover plate; an electrical connector, which is welded on the third pad and electrically connected to the detection element; the electrical connector is used to connect a source meter; the source meter is used to supply power to the detection element and the circuit structure through the electrical connector, and to measure the signal on the detection element. The present invention is used for radiation detectors.

Description

Technical Field

[0001] The invention relates to a diamond detector and a manufacturing method thereof, belonging to the technical field of radiation detection. Background Art

[0002] With the rapid development of high-energy physics and radiation detection in China, more and more fields require certain measurements of nuclear radiation, which puts higher requirements on the performance of radiation detection, such as high sensitivity, high radiation resistance, and long service life.

[0003] Traditional radiation detector materials are mainly first-generation and second-generation semiconductor materials such as silicon, germanium, and gallium arsenide, including silicon-based PIN detectors, silicon-based diode detectors, gallium arsenide detectors, and cadmium zinc telluride detectors. Silicon is the most typical material used for radiation detectors, but its radiation resistance is insufficient, its PIN / PN junction is prone to aging, and its dark current is large. It is still obviously insufficient in the detection of high-energy rays; gallium arsenide detectors have low sensitivity, and due to the limitations of manufacturing level, the interface ohmic contact needs to be improved; cadmium zinc telluride detectors have a large signal-to-noise ratio when testing some high-energy particle signals in a mixed environment, and the carrier mobility is relatively low, which makes it difficult to overcome the "background" problem of time response of cadmium zinc telluride detectors, and there are deficiencies such as large dark current and poor radiation resistance, so they cannot meet the requirements of long service life. Summary of the invention

[0004] The present invention provides a diamond detector and a manufacturing method thereof, which can solve the problems of low sensitivity, poor radiation resistance and short service life of existing radiation detectors.

[0005] On the one hand, the present invention provides a diamond detector, which includes: an installation circuit board, on which a first solder pad, a second solder pad, a third solder pad, and a circuit structure connected to the first solder pad, the second solder pad, and the third solder pad are provided; a detection element, which includes a diamond sheet, and a first electrode and a second electrode arranged on opposite surfaces of the diamond sheet; the first electrode is welded to the first solder pad, and the second electrode is connected to the second solder pad; a fixed cover plate, which is arranged on a side of the installation circuit board close to the detection element and is used to encapsulate components on the installation circuit board; a radiation window is opened on the fixed cover plate, and the radiation window corresponds to the position of the detection element and is adapted to the size; an electrical connector, which is welded on the third solder pad and is electrically connected to the detection element; the electrical connector is used to connect a source meter; the source meter is used to supply power to the detection element and the circuit structure through the electrical connector, and to measure the signal on the detection element.

[0006] Optionally, the detector also includes an intermediate limiting plate arranged between the mounting circuit board and the fixed cover plate; the intermediate limiting plate is provided with an avoidance opening and an avoidance channel; the avoidance opening is used to avoid the detection element; and the avoidance channel is used to avoid the electrical connector and the circuit structure.

[0007] Optionally, the second electrode is connected to the second pad by wire bonding.

[0008] Optionally, the mounting circuit board, the intermediate limiting plate and the fixed cover plate are all provided with fixing holes; the detector further comprises fasteners, and the fasteners pass through the fixing holes to fix the mounting circuit board, the intermediate limiting plate and the fixed cover plate.

[0009] Optionally, metal layers are provided on the front and back surfaces of the mounting circuit board, the middle limiting plate and the fixed cover plate.

[0010] Optionally, the mounting circuit board, the middle limiting plate and the fixed cover plate are all provided with plated through holes.

[0011] Optionally, a gold layer is disposed on the first pad, the second pad and the third pad.

[0012] On the other hand, the present invention provides a method for manufacturing a diamond detector applied to any of the above-mentioned ones, the manufacturing method comprising: respectively plating a first electrode and a second electrode on two opposite surfaces of a diamond sheet to form a detection element; fixing the first electrode of the detection element to a first solder pad of an installation circuit board, connecting the second electrode to a second solder pad of the installation circuit board, and welding an electrical connector to a third solder pad of the installation circuit board; placing an intermediate limiting plate and a fixed cover plate in sequence on the installation circuit board; and fixing and connecting the installation circuit board, the intermediate limiting plate and the fixed cover plate by fasteners.

[0013] Optionally, before respectively plating the first electrode and the second electrode on two opposite surfaces of the diamond sheet, the manufacturing method further includes: soaking and cleaning the diamond sheet with a mixed solution of concentrated sulfuric acid and hydrogen peroxide; cleaning the diamond sheet again with acetone, alcohol and deionized water; and drying the diamond sheet with nitrogen.

[0014] Optionally, the connecting the second electrode to the second pad of the mounting circuit board specifically includes: connecting the second electrode to the second pad of the mounting circuit board by wire bonding.

[0015] The beneficial effects that the present invention can produce include:

[0016] The diamond detector and the manufacturing method thereof provided by the present invention adopt a diamond element as a radiation detection element, and install the detection element into a measuring structure to form a diamond detector, and the finished product has a simple structure and is easy to manufacture; at the same time, since the diamond element is used as the detection element to measure nuclear radiation, higher sensitivity, better radiation resistance and longer service life can be obtained. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic diagram of the structure of a detection element in a diamond detector provided by an embodiment of the present invention;

[0018] Figure 2 A schematic diagram of a peripheral measurement structure in a diamond detector provided by an embodiment of the present invention;

[0019] Figure 3 The process of manufacturing the diamond detector provided by the embodiment of the present invention Figure 1 ;

[0020] Figure 4 The process of manufacturing the diamond detector provided by the embodiment of the present invention Figure 2 .

[0021] List of parts and reference numerals:

[0022] 11. Diamond sheet; 12. First electrode; 13. Second electrode; 14. Mounting circuit board; 15. First solder pad; 16. Fixed cover plate; 17. Radiation window; 18. Electrical connector; 19. Intermediate limiting plate. DETAILED DESCRIPTION

[0023] The present invention is described in detail below in conjunction with embodiments, but the present invention is not limited to these embodiments.

[0024] Diamond is an ultra-wide bandgap semiconductor material with a series of performance advantages, making it an ideal material for making radiation detectors. In recent years, with the gradual improvement of the quality and single crystal size of diamond grown by CVD homoepitaxial growth, the research and application of diamond detectors have entered a new field, promoting the application and development of diamond detectors in space and plasma physics.

[0025] The embodiment of the present invention provides a diamond detector, such as Figure 1 and Figure 2As shown, the detector includes: a mounting circuit board 14, on which a first pad 15, a second pad, a third pad, and a circuit structure connected to the first pad 15, the second pad, and the third pad are arranged; a detection element, the detection element includes a diamond sheet 11, and a first electrode 12 and a second electrode 13 arranged on opposite surfaces of the diamond sheet 11; the first electrode 12 is welded on the first pad 15, and the second electrode 13 is connected to the second pad; a fixed cover plate 16, which is arranged on a side of the mounting circuit board 14 close to the detection element and is used to encapsulate the components on the mounting circuit board 14; a radiation window 17 is opened on the fixed cover plate 16, and the radiation window 17 corresponds to the position of the detection element and is adapted to the size; an electrical connector 18, which is welded on the third pad and electrically connected to the detection element; the electrical connector 18 is used to connect a source meter; the source meter is used to supply power to the detection element and the circuit structure through the electrical connector 18 and to measure the signal on the detection element.

[0026] Among them, the first electrode 12 and the second electrode 13 are both metal electrodes. In practical applications, the diamond sheet 11 can be first soaked and cleaned in a concentrated sulfuric acid / hydrogen peroxide mixed solution, then cleaned with acetone, alcohol and deionized water, and dried with a nitrogen gun; after the diamond sheet 11 is cleaned, it is placed in a plating cavity, and metal electrodes are plated on the front and back surfaces of the diamond sheet 11; to form the first electrode 12 and the second electrode 13. The embodiment of the present invention does not limit the specific plating method, and for example, it can be made by evaporation, sputtering, chemical deposition, etc.

[0027] The first electrode 12 is fixed on the first pad 15 of the mounting circuit board 14, and the second electrode 13 is connected to the second pad on the mounting circuit board 14 by wire bonding. Meanwhile, the electrical connector 18 is welded on the mounting circuit board 14. The wire in the wire bonding method can be a gold wire.

[0028] refer to Figure 2 As shown, a radiation window 17 is left on the fixed cover plate 16 just above the detection element, so that external radiation can irradiate the diamond detection element.

[0029] In the embodiment of the present invention, there are generally two electrical connectors 18, which are connected to the source meter to supply power to the diamond detection element and measure the signal; the radiation is incident on the diamond detection element from the radiation window 17 on the fixed cover plate 16, thereby generating an electrical signal inside the diamond sheet 11.

[0030] The diamond detector can be used to measure alpha particles, neutrons and gamma rays. Under an electric field strength of 1V / μm, the measured dark current of the detector can be as low as 10pA. The diamond detector shows good detection performance for alpha particles, neutrons and gamma rays.

[0031] The present invention adopts a diamond element as a radiation detection element and installs the detection element into a measuring structure to produce a diamond detector, and the finished product has a simple structure and is easy to produce. At the same time, since the diamond element is used as the detection element to measure nuclear radiation, higher sensitivity, better radiation resistance and longer service life can be obtained.

[0032] Furthermore, the detector further includes an intermediate limiting plate 19 disposed between the mounting circuit board 14 and the fixed cover plate 16; the intermediate limiting plate 19 is provided with an escape opening and an escape passage; the escape opening is used to escape the detection element; and the escape passage is used to escape the electrical connector 18 and the circuit structure. The escape opening and the escape passage can facilitate the arrangement of the electrical connector 18 and the components and circuits on the mounting circuit board 14.

[0033] The mounting circuit board 14, the intermediate limiting plate 19 and the fixed cover plate 16 are all provided with fixing holes; the detector further comprises a fastener, which passes through the fixing holes to fix the mounting circuit board 14, the intermediate limiting plate 19 and the fixed cover plate 16. The fastener may be a screw, and specifically, the intermediate limiting plate 19 and the fixed cover plate 16 may be placed on the mounting circuit board 14 in sequence, and then fixed together with screws.

[0034] Furthermore, metal layers are provided on the front and back surfaces of the mounting circuit board 14, the middle limiting plate 19 and the fixed cover plate 16. The metal layers can shield external electromagnetic interference.

[0035] The mounting circuit board 14 , the middle limiting plate 19 and the fixed cover plate 16 are all provided with electroplated through holes.

[0036] A gold layer is disposed on the first pad 15, the second pad and the third pad. Plating the gold layer on the first pad 15, the second pad and the third pad of the mounting circuit board 14 can enhance the conductivity.

[0037] Another embodiment of the present invention provides a method for manufacturing a diamond detector as described above. Figure 3 As shown, the manufacturing method comprises:

[0038] Step 31 : A first electrode 12 and a second electrode 13 are plated on two opposite surfaces of the diamond sheet 11 to form a detection element.

[0039] Step 32 , fix the first electrode 12 of the detection element on the first pad 15 of the mounting circuit board 14 , connect the second electrode 13 to the second pad of the mounting circuit board 14 , and weld the electrical connector 18 to the third pad of the mounting circuit board 14 .

[0040] The second electrode 13 is connected to the second pad of the mounting circuit board 14, which can be specifically:

[0041] The second electrode 13 is connected to the second pad of the mounting circuit board 14 by wire bonding.

[0042] Step 33: Place the middle limiting plate 19 and the fixed cover plate 16 on the mounting circuit board 14 in sequence.

[0043] Step 34: fix the mounting circuit board 14, the middle limiting plate 19 and the fixed cover plate 16 together by fasteners.

[0044] For further reference, Figure 4 As shown, before the first electrode 12 and the second electrode 13 are respectively plated on two opposite surfaces of the diamond sheet 11, the manufacturing method further includes:

[0045] Step 35: Use a mixed solution of concentrated sulfuric acid and hydrogen peroxide to soak and clean the diamond sheet 11.

[0046] Step 36: Clean the diamond sheet 11 again using acetone, alcohol and deionized water.

[0047] Step 37: Dry the diamond sheet 11 using nitrogen.

[0048] The present invention adopts a diamond element as a radiation detection element and installs the detection element into a measuring structure to produce a diamond detector, and the finished product has a simple structure and is easy to produce. At the same time, since the diamond element is used as the detection element to measure nuclear radiation, higher sensitivity, better radiation resistance and longer service life can be obtained.

[0049] The above are only a few embodiments of the present application and do not constitute any form of limitation to the present application. Although the present application is disclosed as above with preferred embodiments, it is not intended to limit the present application. Any technician familiar with the profession, without departing from the scope of the technical solution of the present application, using the technical content disclosed above to make slight changes or modifications are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A diamond detector, characterized in that: The detector comprises: A mounting circuit board, wherein the mounting circuit board is provided with a first solder pad, a second solder pad, a third solder pad, and a circuit structure connected to the first solder pad, the second solder pad, and the third solder pad; A detection element, the detection element comprising a diamond sheet, and a first electrode and a second electrode disposed on opposite surfaces of the diamond sheet; the first electrode is welded to the first pad, and the second electrode is connected to the second pad; A fixed cover plate is arranged on a side of the mounting circuit board close to the detection element, and is used to encapsulate the components on the mounting circuit board; a radiation window is provided on the fixed cover plate, and the radiation window corresponds to the position of the detection element and is adapted to the size; an electrical connector, welded on the third pad and electrically connected to the detection element; the electrical connector is used to connect a source meter; the source meter is used to supply power to the detection element and the circuit structure through the electrical connector and measure the signal on the detection element; The detector further comprises an intermediate limiting plate arranged between the mounting circuit board and the fixed cover plate; an avoidance opening and an avoidance channel are provided on the intermediate limiting plate; The avoidance opening is used to avoid the detection element; the avoidance channel is used to avoid the electrical connector and the circuit structure; The front and back surfaces of the mounting circuit board, the middle limiting plate and the fixed cover plate are all provided with metal layers.

2. The diamond detector according to claim 1, characterized in that: The second electrode is connected to the second pad by wire bonding.

3. The diamond detector according to claim 1, characterized in that: The mounting circuit board, the intermediate limiting plate and the fixing cover plate are all provided with fixing holes; The detector further includes a fastener, which passes through the fixing hole to fix the mounting circuit board, the intermediate limiting plate and the fixing cover plate.

4. The diamond detector according to claim 1, characterized in that: The mounting circuit board, the middle limiting plate and the fixed cover plate are all provided with electroplated through holes.

5. The diamond detector according to claim 1, characterized in that: A gold layer is disposed on the first pad, the second pad and the third pad.

6. A method for manufacturing a diamond detector according to any one of claims 1 to 5, characterized in that: The production method comprises: A first electrode and a second electrode are respectively plated on two opposite surfaces of the diamond sheet to form a detection element; Fixing the first electrode of the detection element on the first pad of the mounting circuit board, connecting the second electrode to the second pad of the mounting circuit board, and welding the electrical connector to the third pad of the mounting circuit board; Placing the middle limiting plate and the fixed cover plate on the mounting circuit board in sequence; The mounting circuit board, the middle limiting plate and the fixed cover plate are fixedly connected by fasteners.

7. The manufacturing method according to claim 6, characterized in that: Before respectively plating the first electrode and the second electrode on two opposite surfaces of the diamond sheet, the manufacturing method further comprises: Using a mixed solution of concentrated sulfuric acid and hydrogen peroxide to soak and clean the diamond sheet; The diamond sheet was cleaned again with acetone, alcohol and deionized water; The diamond sheet was dried using nitrogen gas.

8. The manufacturing method according to claim 6, characterized in that: The second electrode is connected to the second pad of the mounting circuit board, specifically: The second electrode is connected to the second pad of the mounting circuit board by wire bonding.

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