Diamond detector and detection system

Abstract

The invention belongs to the technical field of radiation detection, and particularly relates to a diamond detector and a detection system. The diamond detector is used for calibrating or monitoring the radiation dose of small-field radiotherapy, and comprises a diamond body, a first electrode and a second electrode, a protective layer for preventing the quality of the diamond body from declining is arranged on the outer surface of the diamond body; the first electrode and the second electrode are arranged on the opposite surfaces of the diamond body respectively. According to the diamond detector provided by the invention, the diamond body has anti-radiation and solar-blind characteristics, the service life of the diamond detector can be effectively prolonged, the monitoring precision of the diamond detector can be effectively improved, and the first electrode and the second electrode are respectively arranged on a group of opposite surfaces with the minimum spacing of the diamond body, so that the inter-electrode spacing is reduced; the sensitivity of the diamond detector is improved, so that the diamond detector can meet the calibration or monitoring of the radiation dose of small-field radiotherapy, and the use cost is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of radiation detection, and particularly relates to a diamond detector and a detection system. Background Art

[0002] In the radiation research and radiation applications of radiology and instruments, space radiation, reactor and accelerator radiation fields, etc., accurately measuring the radiation dose is a very important task. In recent years, due to the decommissioning of nuclear power plants and the increase in beam intensity and flux in high-energy experiments, the demand for electronic devices that can adapt to special environments has been increasing. Especially in future experiments, the radiation detectors will be in a radiation environment that is several orders of magnitude more severe than any current detector. Therefore, the requirements for the test detectors used are very strict. Both the sensor material and the electronic device need to have extremely high radiation resistance to provide the high-precision information required for physical analysis.

[0003] As a good detector, in addition to having a small measurement error and good repeatability, it should also meet the requirements of stable performance, good linearity, long life, radiation resistance, high spatial resolution and high sensitivity. Especially in radiotherapy, accurate radiation dose measurement is crucial for the radiotherapy effect and personal safety.

[0004] Currently, the commonly used detectors mainly include ionization chambers and silicon semiconductors. Among them, The ionization chamber has a large volume and cannot be used for calibrating or monitoring the radiation dose of small-field radiotherapy. Moreover, during use, temperature and air pressure corrections are required. The detection structure is easily affected by the environment and is also easily damaged. The silicon semiconductor detector has poor energy response, is not resistant to radiation damage, has a short service life, and increases the use cost. Therefore, inventing a detector with a long life and capable of calibrating or monitoring the radiation dose of small-field radiotherapy is a technical problem that needs to be solved urgently by those skilled in the art. Summary of the Invention

[0005] On the one hand, the present invention provides a diamond detector to solve the technical problems in the prior art that the detector is not resistant to radiation damage, has a low service life, and increases the use cost.

[0006] The present invention is realized through the following technical solutions: A diamond detector for calibrating or monitoring the radiation dose of small-field radiotherapy, comprising a diamond body, a first electrode and a second electrode; A protective layer for preventing the quality decline of the diamond body is provided on the outer surface of the diamond body; The first electrode and the second electrode are respectively arranged on a group of opposite surfaces with the smallest distance between the diamond bodies.

[0007] To better implement the present invention, further optimization is made to the above structure. The first electrode and the second electrode are both plated on the diamond body by electron beam evaporation.

[0008] To better implement the present invention, further optimization is made to the above structure. The first electrode and the second electrode are both Ti / Au electrodes or Ti / AL electrodes.

[0009] To better implement the present invention, further optimization is made to the above structure. The diamond detector further includes a detection fixture; The detection fixture is electrically connected to the detection main body, and the clamping end of the detection fixture is used to clamp the first electrode and the second electrode.

[0010] To better implement the present invention, further optimization is made to the above structure. The detection fixture includes a conductive elastic piece A, a conductive elastic piece B, an insulating body, and a connecting wire; The conductive elastic piece A and the conductive elastic piece B are arranged in parallel on the insulating body. The connecting ends of the conductive elastic piece A and the conductive elastic piece B both extend from the tail of the insulating body to be electrically connected to the connecting wire; The clamping ends of the conductive elastic piece A and the conductive elastic piece B are respectively provided with a contact point A and a contact point B. The conductive elastic piece A and the conductive elastic piece B are respectively clamped on the first electrode and the second electrode, and are electrically connected to the first electrode and the second electrode through the contact point A and the contact point B.

[0011] To better implement the present invention, further optimization is made to the above structure. The first electrode and the second electrode both lead out and connect a cable through bonding, and the connecting cable is a TNC cable.

[0012] To better implement the present invention, further optimization is made to the above structure. A filter layer for filtering invalid spectra is arranged outside the diamond body, and the connecting end of the connecting cable is located outside the filter layer.

[0013] To better implement the present invention, further optimization is made to the above structure. The filter layer includes an epoxy resin layer and a plexiglass layer; The epoxy resin layer is coated outside the diamond body, and the plexiglass layer is coated outside the epoxy resin layer.

[0014] To better implement the present invention, further optimization is made to the above structure. The diamond body is a rectangular block structure or a cylindrical structure. The thickness of the diamond body is 0.4 mm to 1 mm, and the side length or diameter of the diamond body is 1 mm to 4 mm.

[0015] On the other hand, the present invention also provides a detection system, including a detection main body and the above-mentioned diamond detector; The diamond detector is installed on the detection main body, and the first electrode and the second electrode in the diamond detector are electrically connected to the detection main body.

[0016] The present invention has the following beneficial effects compared with the prior art: In the diamond detector provided by the present invention, the diamond body has anti-radiation and solar-blind characteristics, which can effectively improve the service life and monitoring accuracy of the diamond detector. Moreover, the first electrode and the second electrode are respectively arranged on a group of opposite surfaces with the smallest distance between the diamond bodies to reduce the pole pitch and improve the sensitivity of the diamond detector, so that it can meet the calibration or monitoring of the radiation dose in small-field radiotherapy and reduce the use cost.

[0017] In addition, the diamond body in the diamond detector has a wide forbidden band, which can meet the requirements of working at high temperatures, and has high electron and hole mobility and saturation drift velocity. Therefore, it has a fast response, and a low atomic number, which is close to the atomic number of human soft tissue, has tissue equivalence, and can simulate the response of biological tissue in the radiation field to better achieve the calibration or monitoring of the radiation dose. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0019] Figure 1 is a schematic structural diagram of a diamond detector of the present invention.

[0020] Figure 2 is Figure 1 a partial enlarged view of part A in

[0021] Figure 3 is a schematic structural diagram of a detection fixture in a diamond detector of the present invention.

[0022] Figure 4 is a schematic diagram of one usage mode of a diamond detector of the present invention (a filter layer is arranged on the surface of the diamond body).

[0023] Figure 5 is a schematic diagram of another usage mode of a diamond detector of the present invention (a filter layer is not arranged on the surface of the diamond body).

[0024] In the figure: 1. Diamond body; 21. First electrode; 22. Second electrode; 3. Protective layer; 4. Connecting cable; 51. Epoxy resin layer; 52. Plexiglass layer 6. Detection fixture; 61. Conductive elastic sheet A; 62. Conductive elastic sheet B; 63. Insulating body; 64. Connecting wire. Specific embodiments

[0025] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be described in detail below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without any creative effort fall within the scope of protection of the present invention.

[0026] In the description of the present invention, it should be noted that unless otherwise specified, the meaning of "a plurality" is two or more; the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation of the present invention. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0027] In the description of the present invention, it should also be noted that unless otherwise clearly specified and limited, the terms "installation", "connection", and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0028] In the embodiments of the present application, as Figures 1 to 4 shown, the diamond detector includes a diamond body 1, a first electrode 21, and a second electrode 22; wherein, A protective layer 3 is provided on the outer surface of the diamond body 1, and the protective layer 3 can prevent the diamond body 1 from experiencing mass decline, resulting in an increase in the interfacial thermal resistance of the diamond body 1, and further affecting the performance of the diamond body 1. The first electrode 21 and the second electrode 22 are respectively arranged on a group of opposite surfaces of the diamond body 1 with the smallest distance therebetween. Refer to Figure 2 , in this embodiment, the above-mentioned diamond body 1 is in a rectangular block structure or a cylindrical structure. The thickness of the diamond body 1 is 0.4 mm to 1 mm. When the diamond body 1 is in a cylindrical structure, its diameter is 1 mm to 4 mm; when the diamond body 1 is in a rectangular block structure, the side length of the diamond body 1 is 1 mm to 4 mm to determine the volume of the diamond body 1. A group of opposite surfaces of the above-mentioned diamond body 1 with the smallest distance therebetween are namely two end faces in the height direction of the diamond body 1; The first electrode 21 and the second electrode 22 are respectively arranged at two ends in the thickness direction of the diamond body 1 to reduce the pole pitch of the diamond body 1 and improve the sensitivity of its reaction; and the first electrode 21 and the second electrode 22 are arranged close to one side thereof to avoid the first electrode 21 or the second electrode 22 affecting the incidence of radiation rays. The diamond detector with the above structure can be applicable to the calibration or monitoring of the radiation dose in small-field (such as gamma knife) radiotherapy.

[0029] And according to the size of the above-mentioned diamond body 1, the measurement field range of this diamond detector is (1×1) cm 2 ~(40×40) cm 2 .

[0030] This diamond detector is connected to the detection main body through the first electrode 21 and the second electrode 22. When a radiation beam irradiates on the diamond body 1, the detection value displayed on the detection main body will change to realize the monitoring of the intensity and spatial position of the radiation beam.

[0031] It should be noted that the quality degradation of the above-mentioned diamond body 1 refers to the purity attenuation of the diamond body 1. After the purity of the diamond body 1 attenuates, it will cause excessive leakage and measurement value drift, affecting the monitoring accuracy. The protective layer 3 can be a silicon dioxide or Parylene coating (Parylene, a new conformal coating material).

[0032] The diamond body 1 can also be set to other shapes. In this embodiment, setting the diamond body 1 as a rectangular block or a cylindrical structure is only for facilitating the processing of the first electrode 21 and the second electrode 22; The diamond body 1 is a high-quality single-crystal diamond homogeneously grown by using the MPCVD method (microwave plasma chemical vapor deposition method) with a diamond seed to reduce the preparation cost of this diamond detector; of course, the diamond body 1 can also be polycrystalline diamond.

[0033] In addition, this diamond detector is at 140 kV to 280 kV and 100 kV to 60In the monitoring of the radiation energy range of Co, its error range ≤ ±4%, with high accuracy, and the long-term stability and repeatability of this diamond detector are both less than 0.5%, and the indication non-linearity is ±0.5%. Among them, the above-mentioned 60 Co refers to a gamma-ray source, and its average emitted energy is 1.25 MeV. That is, in the monitoring of the radiation energy range from 100 kV to 1.25 MeV, its error range ≤ ±4%.

[0034] In some embodiments, the above-mentioned first electrode 21 and second electrode 22 are both plated on the diamond body 1 by electron beam evaporation, and the thicknesses of the first electrode 21 and the second electrode 22 are both 0.05 μm to 1 μm.

[0035] In some embodiments, the above-mentioned first electrode 21 and second electrode 22 are both Ti / Au electrodes or Ti / Al electrodes. Among them, Ti in the Ti / Au electrode or Ti / Al electrode can form a good ohmic contact with the diamond body 1, so that no obvious additional impedance is generated between them, and the equilibrium carrier concentration inside the diamond body 1 will not be significantly changed, so as to ensure the monitoring accuracy of this diamond detector.

[0036] In some embodiments, the above-mentioned first electrode 21 and second electrode 22 are both led out through bonding to connect the cable 4 to ensure the stability of the connection between the first electrode 21 and the second electrode 22 and the cable 4. Preferably, the cable 4 is a TNC cable (radio frequency coaxial cable).

[0037] In some embodiments, a filter layer for filtering invalid spectra is provided outside the above-mentioned diamond body 1 to further improve the monitoring accuracy of this diamond detector, and the connection end of the above-mentioned cable 4 is located outside the filter layer.

[0038] Specifically, the above-mentioned filter layer includes an epoxy resin layer 51 and a plexiglass layer 52, see Figure 1 and Figure 2 ; among them, The epoxy resin layer 51 is coated outside the diamond body 1, and the plexiglass layer 52 is coated outside the epoxy resin layer 51; The epoxy resin layer 51 and the plexiglass layer 52 can effectively filter the invalid spectra in the radiation beam to improve the monitoring accuracy of this diamond detector.

[0039] In some embodiments, this diamond detector further includes a detection fixture 6, see Figure 4 ; among them, The detection fixture 6 is electrically connected to the detection body. The clamping end of the detection fixture 6 is used to clamp the first electrode 21 and the second electrode 22. By clamping and fixing the diamond body 1 with the detection fixture 6, the rapid installation and disassembly of the diamond body 1 can be realized, so as to facilitate the replacement of diamond bodies 1 with different thicknesses according to the usage situation, thereby making the use of this diamond detector more convenient.

[0040] It should be noted that, in order to avoid recombination losses of the radiation beam due to excessive pole pitch during the calibration or monitoring of the radiation dose in small-field radiotherapy, after determining the radiation intensity, diamond bodies 1 with different thicknesses can be selected according to the radiation intensity. As the intensity of the radiation beam increases, the thickness of the diamond body 1 must be reduced, that is, the pole pitch of the diamond body 1 is reduced, so as to ensure the monitoring accuracy of this diamond detector.

[0041] In some embodiments, the above-mentioned detection fixture 6 includes a conductive spring piece A61, a conductive spring piece B62, an insulating body 63 and a connecting wire 64. Refer to Figure 3 ; wherein, The conductive spring piece A61 and the conductive spring piece B62 are arranged in parallel on the insulating body 63 to avoid short-circuiting between the conductive spring piece A61 and the conductive spring piece B62. The connecting ends of the conductive spring piece A61 and the conductive spring piece B62 both extend from the tail of the insulating body 63 and are electrically connected to the connecting wire 64; The clamping ends of the conductive spring piece A61 and the conductive spring piece B62 are respectively provided with a contact point A and a contact point B. The conductive spring piece A61 and the conductive spring piece B62 are respectively clamped on the first electrode 21 and the second electrode 22, and are electrically connected to the first electrode 21 and the second electrode 22 through the contact point A and the contact point B, so as to make the installation and disassembly of the diamond body 1 more convenient.

[0042] Of course, in the case where no filter layer is provided on the surface of the diamond body 1, it can also be used in cooperation with the above-mentioned detection fixture 6. Refer to Figure 5 .

[0043] Through the above embodiments, the vertical detector provided by the present invention has the following technical effects: (1) The diamond body 1 in this diamond detector has anti-radiation and solar-blind characteristics, which can effectively improve the service life and monitoring accuracy of this diamond detector. Moreover, the first electrode 21 and the second electrode 22 are respectively arranged on a group of opposite surfaces of the diamond body 1 with the smallest distance, so as to reduce the pole pitch and improve the sensitivity of this diamond detector, enabling it to meet the calibration or monitoring of the radiation dose in small-field radiotherapy, thereby reducing the use cost.

[0044] (2) In this diamond detector, the diamond body 1 has a wide bandgap, which can meet the requirements of high-temperature operation, and has high electron and hole mobility and saturation drift velocity. Therefore, it has a fast response, and a relatively low atomic number, which is close to that of human soft tissue, and has tissue equivalence, and can simulate the response of biological tissue in the radiation field to better achieve the calibration or monitoring of radiation dose.

[0045] Based on the above diamond detector, the present invention further provides a detection system, which includes a detection main body and the above diamond detector; The diamond detector is installed on the detection main body, and the first electrode 21 and the second electrode 22 in the diamond detector are electrically connected to the detection main body.

[0046] The diamond detector in this detection system has anti-radiation and solar-blind characteristics, which can effectively improve the service life and monitoring accuracy of the diamond detector, meet the calibration or monitoring of radiation dose in small-field radiotherapy, and reduce the use cost.

[0047] The above detection main body can be a medical accelerator, an X-ray deep therapy machine, and 60 a CO therapy machine to be applicable to different environments.

[0048] The above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of changes or substitutions, which should all be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claimed rights.

Claims

1. A diamond detector for calibrating or monitoring radiation dose in small field radiotherapy, characterized in that: It comprises a diamond body (1), a first electrode (21) and a second electrode (22); The outer surface of the diamond body (1) is provided with a protective layer (3) for preventing the quality of the diamond body (1) from deteriorating; The first electrode (21) and the second electrode (22) are respectively arranged on a group of opposite surfaces of the diamond body (1) with the smallest spacing therebetween.

2. The diamond detector according to claim 1, characterized in that: The first electrode (21) and the second electrode (22) are both plated on the diamond body (1) by electron beam evaporation.

3. The diamond detector according to claim 2, characterized in that: The first electrode (21) and the second electrode (22) are both Ti / Au electrodes or Ti / Al electrodes.

4. The diamond detector according to any one of claims 1 to 3, characterized in that: The diamond detector further comprises a detection fixture (6); The detection fixture (6) is electrically connected to the detection body, and the clamping end of the detection fixture (6) is used to clamp the first electrode (21) and the second electrode (22).

5. The diamond detector according to claim 4, characterized in that: The detection fixture (6) comprises a conductive spring piece A (61), a conductive spring piece B (62), an insulating body (63) and a connecting wire (64); The conductive spring piece A (61) and the conductive spring piece B (62) are arranged in parallel on the insulating body (63), and the connecting end of the conductive spring piece A (61) and the connecting end of the conductive spring piece B (62) are both extended from the tail of the insulating body (63) to be electrically connected to the connecting wire (64); A clamping end of the conductive spring sheet A (61) and a clamping end of the conductive spring sheet B (62) are provided with a contact point A and a contact point B, respectively; the conductive spring sheet A (61) and the conductive spring sheet B (62) are clamped on the first electrode (21) and the second electrode (22), respectively, and are electrically connected to the first electrode (21) and the second electrode (22) via the contact point A and the contact point B.

6. The diamond detector according to claim 1, characterized in that: The first electrode (21) and the second electrode (22) are both connected to a connecting cable (4) through bonding, and the connecting cable (4) is a TNC cable.

7. The diamond detector according to claim 6, characterized in that: A filter layer for filtering invalid light spectra is arranged outside the diamond body (1), and a connection end of the connection cable (4) is located outside the filter layer.

8. The diamond detector according to claim 7, characterized in that: The filter layer comprises an epoxy resin layer (51) and an organic glass layer (52); The epoxy resin layer (51) is coated on the outside of the diamond body (1), and the organic glass layer (52) is coated on the outside of the epoxy resin layer (51).

9. The diamond detector according to claim 1, characterized in that: The diamond body (1) is a rectangular block structure or a cylindrical structure, the thickness of the diamond body (1) is 0.4 mm to 1 mm, and the side length or diameter of the diamond body (1) is 1 mm to 4 mm.

10. A detection system, characterized in that: It comprises a detection body and the diamond detector according to claim 1; The diamond detector is mounted on the detection body, and the first electrode (21) and the second electrode (22) in the diamond detector are electrically connected to the detection body.

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