Design method and detection method of high-energy proton detection probe based on stacked cadmium zinc telluride

Abstract

This invention discloses a design method and detection method for a high-energy proton detection probe based on stacked cadmium zinc telluride (CZN), specifically involving the detection of protons with an energy of 100 MeV, belonging to the field of space particle measurement technology. The method steps are as follows: (1) screening the electrostatic shielding material of the stacked CZN probe; (2) calculating the number of layers and size of the stacked CZN semiconductor using the TRIM module in the SRIM software package of the Monte Carlo algorithm; (3) simulating the electrode structure and size of the stacked CZN detector using the AC / DC electrostatic module in the finite element software Comsol Multiphysics; (4) connecting each layer of the CZN detector to a preamplifier, then inputting the signal into an additive circuit for signal superposition, and then acquiring the energy spectrum through a main amplifier, multichannel, and computer. The method can detect high-energy protons with high energy resolution and accurate measurement results. The method is practical and feasible, and can serve space exploration activities.

Description

Technical Field

[0001] This invention belongs to the field of space particle measurement technology, and specifically relates to the design and detection methods of a high-energy proton detector based on stacked cadmium zinc telluride. Background Technology

[0002] Space particle detection is essential for human space activities and a prerequisite for understanding and studying space and venturing into outer space. In the radiation belts, high-energy protons have a lifetime of up to 8000 years. Currently, the analysis of the radiation belts is primarily qualitative and statistical, while the loss mechanisms and processes of high-energy particles in the inner radiation belts, especially the changes in high-energy particle flux during geomagnetic storms, require further investigation. Monitoring the flux, energy, and distribution of particles within the radiation belts can provide a clearer understanding of the generation and loss processes of high-energy particles, laying the foundation for quantitatively calculating the changes in high-energy particle flux under various conditions.

[0003] Cadmium zinc telluride (CZT) detectors have advantages such as small size, room temperature operation, and durability. However, current CZT detectors are mainly used for X-ray and gamma-ray detection, with limited application in charged particle measurement. Charged particle detection requires CZT detectors to have high energy resolution, high reliability, and broad applicability. Summary of the Invention

[0004] To address the limitations of traditional cadmium zinc telluride (CZN) detectors, which can only detect X-rays and gamma rays, this invention proposes a design and detection method for a high-energy proton detector based on stacked CZN, specifically a method for detecting protons with an energy of 100 MeV.

[0005] The technical solution of this invention is as follows: a design method for a high-energy proton detection probe based on stacked zinc cadmium telluride (CdZN). The high-energy proton detection probe includes several detection units, an electrostatic shielding layer 1, a metal shell 16, a base 9, several preamplifier circuits, and an additive circuit. The metal shell 16 is open at both ends, with the electrostatic shielding layer 1 connected to the top and the base 9 located inside the bottom. Several detection units are placed parallel to each other inside the metal shell 16, and several preamplifier circuits are placed vertically inside the metal shell 16. There is no contact between the detection units or between the preamplifier circuit units. The additive circuit is located inside the metal shell 16 and placed on the base 9. A Remer interface is located below the base 9, and the Remer interface is connected to the additive circuit via a cable. The preamplifier circuit is connected to the additive circuit.

[0006] The design method includes the following steps:

[0007] Step 1: Material selection for the electrostatic shielding layer: Select a material with a surface resistivity of less than 1×10⁻⁶. 4Ω / m 2 Or the volume resistivity does not exceed 1×10 3 Materials with Ω·cm;

[0008] Step 2: Design of the detection unit: The detection unit consists of several cadmium zinc telluride detectors, with a cadmium zinc telluride semiconductor as the substrate and electrodes on the outside. The cadmium zinc telluride semiconductor and electrodes are designed separately. The number of cadmium zinc telluride detectors must ensure that the incident protons can fall exactly into the last layer of cadmium zinc telluride detectors at the end.

[0009] A further technical solution of the present invention is as follows: In step 2, the design of the zinc cadmium telluride semiconductor is such that the semiconductor density is 5.8 g / cm³. 3 The Cd:Zn:Te ratio is 0.9:0.1:1; the thickness is 1-5mm.

[0010] A further technical solution of the present invention is as follows: In step 2, the semiconductor electrode structure design of the cadmium zinc telluride detector includes the following steps:

[0011] Step 2.1: Add a working surface at the electrode of the zinc cadmium telluride electrode, treat the working surface as the electrode, apply voltage to the anode and cathode respectively, and use automatic meshing with extra fine meshing; extract and output the electric field distribution and potential distribution data of the mid-section.

[0012] Step 2.2: Based on the electric field distribution and potential distribution data of the mid-section obtained in Step 2.1, determine the appropriate electrode structure.

[0013] A further technical solution of the present invention is as follows: In step 2.1, the cathode surface is connected to 0V and the anode surface is subjected to high voltage.

[0014] A further technical solution of the present invention is as follows: In step 2.2, from the perspective of potential distribution, since the change in potential corresponds to the change in weighted potential field, the more rapidly the weighted potential changes near the anode, the more the structure and size of the electrode meet the requirements; from the perspective of electric field distribution, the stronger the electric field near the anode, the more conducive it is to the rapid collection of electrons drifting to the vicinity of the anode, and at the same time to the drift of holes generated near the anode to the region where the weighted potential of the cathode is slow, then the structure and size of the electrode meet the requirements more.

[0015] A further technical solution of the present invention is as follows: the method for determining whether the overall zinc cadmium telluride detector meets the requirements is: the Bragg curve formed by the ionization energy loss; as the remaining range decreases, the specific ionization gradually increases, reaching a maximum value at the end of the remaining range - the Bragg peak; if the specific ionization increases in the front end position and forms an obvious Bragg peak in the last layer of zinc cadmium telluride semiconductor, it indicates that the stacked detector structure meets the requirements.

[0016] A further technical solution of the present invention is: a detection method for a high-energy proton detection probe of stacked tellurium zinc cadmium, comprising the following steps:

[0017] Step 1: The incident proton enters the i-th layer of the cadmium zinc telluride detector, where the energy deposited is ΔEi, which generates a pulse charge signal on the detector Di.

[0018] Step 2: The pulse charge signal generated by the detector Di is sent to the input terminal of the pre-processing circuit board Si through the signal cable and enters the i-th preamplifier;

[0019] Step 3: The i-th preamplifier amplifies the pulse charge signal from detector Di for the first time and outputs it to the summing circuit;

[0020] Step 4: The summing circuit superimposes the pulse charge signals from the i-th preamplifier and outputs them to the main amplifier;

[0021] Step 5: The main amplifier shapes and amplifies the pulse charge signal from the summing circuit, outputs it to the multichannel, and finally sends it to the computer to obtain the total spectrum.

[0022] Invention Effects

[0023] The technical advantages of this invention are as follows:

[0024] When 1,100 MeV protons are incident into the cadmium zinc telluride (CZT) detector, the high-energy protons ionize the CZT matrix particles (atoms or molecules), forming electron-hole pairs. At this point, a positive voltage is applied to the anode. Under the influence of the built-in electric field, electrons move towards the anode, and holes move towards the cathode, generating an output signal. However, this requires a very thick CZT semiconductor, increasing the probability of carriers being trapped by defects. Therefore, this invention employs a stacked CZT detector probe to shorten the carrier drift process, improve the detector's charge collection efficiency, and enhance energy resolution.

[0025] 2. This invention proposes a design and detection method for a high-energy proton detection probe based on stacked cadmium zinc telluride detectors. The probe, composed of stacked cadmium zinc telluride detectors, can detect protons in space at a speed of 91-100 MeV.

[0026] 3. The high-energy proton detection probe made using this method, which is composed of stacked zinc cadmium telluride, can not only detect X-rays and gamma rays, but also detect high-energy protons and electrons, and can achieve high count rate and energy resolution. Attached Figure Description

[0027] Figure 1 (a) is a map showing the horizontal track distribution of 100 MeV protons incident on the stacked structure.

[0028] Figure 1(b) is a vertical track distribution diagram of 100 MeV protons incident on the stacked structure.

[0029] Figure 1 (c) is the range distribution diagram of 100 MeV protons incident on the stacked structure.

[0030] Figure 1 (d) is the energy deposition distribution diagram of 100 MeV protons incident on the stacked structure.

[0031] Figure 2 (a) is a potential distribution diagram inside a planar cadmium zinc telluride detector.

[0032] Figure 2 (b) is a diagram showing the electric field distribution inside a planar cadmium zinc telluride detector.

[0033] Figure 2 (c) is a potential distribution diagram inside a quasi-hemispherical cadmium zinc telluride detector.

[0034] Figure 2 (d) is the electric field distribution inside the quasi-hemispherical cadmium zinc telluride detector.

[0035] Figure 3 This is a schematic diagram of a 100 MeV proton detector.

[0036] Figure 4 This is a two-dimensional schematic diagram of a high-energy proton detection probe based on stacked cadmium zinc telluride.

[0037] Figure 5 This is a schematic diagram of the electrode structure of a cadmium zinc telluride detector.

[0038] Figure 6 This is a three-dimensional schematic diagram of a stacked cadmium zinc telluride detector.

[0039] Explanation of reference numerals in the attached diagram: 1-Electrostatic shielding layer; 2-D1 detection unit; 3-D2 detection unit; 4-D3 detection unit; 5-D4 detection unit; 6-D5 detection unit; 7-S1 preamplifier circuit; 8-S2 preamplifier circuit; 9-Base; 10-Remer connector; 11-Adding circuit; 12-S3 preamplifier circuit; 13-S4 preamplifier circuit; 14-S5 preamplifier circuit; 15-Detector unit support frame; 16-Copper outer casing Detailed Implementation

[0040] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0041] See Figures 1-6 The present invention provides a design and detection method for a high-energy proton detection probe based on stacked zinc cadmium telluride, wherein the probe structure includes several detection units, an electrostatic shielding layer 1, a metal shell 16, a base 9, several preamplifier circuits and summing circuits;

[0042] The metal casing 16 is open at both ends, with an electrostatic shielding layer 1 connected to the top and a base 9 inside the bottom. Several detection units are placed horizontally inside the metal casing 16, and several preamplifier circuits are placed vertically. There is no contact between the detection units and between the preamplifier circuit units.

[0043] The summing circuit is located inside the metal casing 16 and placed on the base 9. The base 9 has a Remer interface below it, and the Remer interface is connected to the summing circuit via a cable. The preamplifier circuit is connected to the summing circuit.

[0044] The detection unit is a cadmium zinc telluride detector, with a cadmium zinc telluride semiconductor substrate and a hemispherical gold electrode plated on the outside. The side with the circular electrode plated is the anode, and the other side and the surrounding area are the cathodes.

[0045] The electrostatic shielding layer 1 is made of beryllium metal.

[0046] The outer wall of the base 9 has a circumferential groove for holding the plastic shell 17 containing the detector, and the outer side has threads for threaded connection with the copper shell 16.

[0047] The detection units are fixedly supported by detection unit support frames. Each layer of the cadmium zinc telluride detector is supported by a detection unit support frame on the top and bottom of the left and right ends. The detection unit support frames are fixed on the plastic shell, and the plastic shell is fitted into the groove of the base for positioning.

[0048] The support frame for the detection unit is made of plastic.

[0049] The number of detection units is 1, 2, ..., n, and 5 ≤ n ≤ 10; the number of preamplifier circuits is 1, 2, ..., m, and 5 ≤ m ≤ 10; the number of m and n are the same, and the detection units and preamplifier circuits are connected in a one-to-one correspondence.

[0050] The design method steps are as follows:

[0051] (1) Selection of electrostatic shielding materials

[0052] According to the principle of electrostatic shielding, the surface resistivity of the material is less than 1×10⁻⁶. 4 Ω / m 2 Or the volume resistivity does not exceed 1×10 3 With a strength of Ω·cm, Faraday shields made from this material can prevent electrostatic discharge (ESD) from affecting ESD-sensitive devices. Furthermore, due to its application in aerospace structural components, it must possess superior nuclear and physical properties. Beryllium's low density, high tensile strength, and excellent conductivity make it an ideal EMI shielding material for use across a wide frequency range. Therefore, beryllium was selected as the ESD shielding material, with a thickness of 200 μm and a density of 1.85 g / cm³. 3 .

[0053] (2) Multilayer Cadmium Zinc Telluride Detector Substrate - Multilayer Cadmium Zinc Telluride Semiconductor Size Design

[0054] Since excessively thick cadmium zinc telluride semiconductors increase the probability of carriers being trapped by defects, thereby reducing carrier collection efficiency, the thickness of each layer of the cadmium zinc telluride detector designed in this invention is 1-5 mm.

[0055] The calculation was performed using the TRIM module in the SRIM software package based on the Monte Carlo algorithm. The input consisted of an electrostatic shielding material with a thickness of 200 μm and several layers of cadmium zinc telluride (CZN) semiconductor material, where the CZN semiconductor density was 5.8 g / cm³. 3 With the Cd:Zn:Te ratio being 0.9:0.1:1, a preliminary simulation was performed to calculate the track of 100 MeV protons in the stacked zinc cadmium telluride semiconductor, as well as the incident depth and ionization energy loss of 100 MeV protons in the stacked zinc cadmium telluride semiconductor.

[0056] Using the TRIM module in the SRIM software package based on the Monte Carlo algorithm, the first layer is named Be, with a thickness of 200 μm and a density of 1.85 g / cm³. 3 The second layer, named CZT1, uses a 5mm thick cadmium zinc telluride semiconductor with a density of 5.8 g / cm³. 3 The Cd:Zn:Te ratio is 0.9:0.1:1; the third layer is named CZT2, and it is an input cadmium zinc telluride semiconductor with a thickness of 5 mm and a density of 5.8 g / cm³. 3The Cd:Zn:Te ratio is 0.9:0.1:1; the fourth layer is named CZT3, and it is an input cadmium zinc telluride semiconductor with a thickness of 5 mm and a density of 5.8 g / cm³. 3 The Cd:Zn:Te ratio is 0.9:0.1:1; the fifth layer is named CZT4, and it contains a 5mm thick cadmium zinc telluride semiconductor with a density of 5.8 g / cm³. 3 The Cd:Zn:Te ratio is 0.9:0.1:1; the sixth layer is named CZT5, and it contains a 5mm thick cadmium zinc telluride semiconductor with a density of 5.8 g / cm³. 3 The Cd:Zn:Te ratio is 0.9:0.1:1. The sample size used in the calculation is 500, and the calculation accuracy is less than 10%. The calculations determine the track of 100 MeV protons in the stacked cadmium zinc telluride semiconductor, as well as the incident depth and ionization energy loss of 100 MeV protons in the stacked cadmium zinc telluride semiconductor.

[0057] like Figure 1 Figures (a) and (b) show the track distribution of 100 MeV protons along the horizontal and vertical incident directions in various probe structures. Due to the relatively light mass of protons, their tracks are more linear than those of heavy ions, exhibiting a funnel-shaped distribution. Significant scattering occurs during incidence, likely due to the large mass of the target atoms in the cadmium zinc telluride crystal, resulting in a larger scattering angle during elastic collisions. TRIM calculations show a longitudinal dispersion of 1.07 mm and a lateral dispersion of 1.60 mm for the 100 MeV protons in the stacked cadmium zinc telluride structure.

[0058] like Figure 1 (c) represents the incident depth of a 100 MeV proton in the stacked cadmium zinc telluride structure, which is 23.5 mm. The thickness of each cadmium zinc telluride detector layer in this invention is 5 mm, requiring 5 layers of cadmium zinc telluride semiconductor to ensure that the 100 MeV proton ultimately lands precisely in the last layer of semiconductor cadmium zinc telluride detector material.

[0059] like Figure 1 (d) shows the Bragg curve formed by 100 MeV protons in the stacked cadmium zinc telluride semiconductor. It can be seen that the loss mechanism of 100 MeV protons in the stacked cadmium zinc telluride structure is mainly ionization energy loss. In the first, second, third and fourth layers, the specific ionization increases with the increase of thickness. A significant Bragg peak is formed in the last layer (fifth layer) of the cadmium zinc telluride semiconductor, which indicates that the stacked detector structure meets the requirements.

[0060] (3) Electrode structure and size design of the stacked cadmium zinc telluride detector

[0061] Since the thickness of each layer of the cadmium zinc telluride detector designed in this invention is 1-5 mm, the number of layers of the cadmium zinc telluride semiconductor is determined by the incident depth of 100 MeV protons in the stacked cadmium zinc telluride semiconductor, and by ensuring that the 100 MeV protons ultimately fall exactly in the last layer of semiconductor cadmium zinc telluride detector material.

[0062] The Bragg curve, or specific ionization curve, formed by the loss of ionization energy, shows that as the remaining range decreases, the specific ionization gradually increases, reaching its maximum value—the Bragg peak—at the end of the remaining range. This is used to determine whether the stacked cadmium zinc telluride structure meets the requirements. If the specific ionization increases at the front end and forms a significant Bragg peak in the last layer of cadmium zinc telluride semiconductor, then the stacked detector structure meets the requirements.

[0063] The AC / DC electrostatic module in the finite element software Comsol Multiphysics was used to simulate planar electrode structures and quasi-hemispherical electrode structures. The detector size was 10×10×5mm. 3 Since cadmium zinc telluride (CZN) was not available in the material library, cadmium telluride (CdTe) was selected, and its dielectric constant was set to 10.6. During the calculation, it was assumed that the electrode and CZN were in ohmic contact. Because the electrode thickness was only 100 nm, it was ignored during modeling and mesh generation to avoid overly dense or incorrect meshing due to its small thickness. The electrode was treated as follows: a working surface was added at the CZN electrode, and the working surface was considered the electrode. A voltage was applied to the working surface: 800 V was applied to the anode, and 0 V to the cathode. The mesh generation method used in the calculation was automatic meshing with extra fineness. The electric field and potential distribution data of the mid-section were extracted and output in full-precision format.

[0064] The appropriate electrode structure is determined based on the electric field and potential distribution of the mid-section. From the perspective of potential distribution, since changes in potential correspond to changes in the weighted potential field, the more rapidly the weighted potential changes near the anode, the more induced charge is generated by electron drift, and the more suitable the electrode structure and size become. From the perspective of electric field distribution, a stronger electric field near the anode is more conducive to the rapid collection of electrons drifting to the anode, while simultaneously causing holes generated near the anode to drift to the region of slower weighted potential at the cathode, further ensuring the electrode structure and size meet the requirements.

[0065] (4) Detection of high-energy protons

[0066] The signal processing system includes i preamplifiers, summing circuits, main amplifier circuits, multichannel, and a computer.

[0067] An incident proton enters the i-th layer of the cadmium zinc telluride detector, where it deposits an energy of ΔEi, generating a pulse charge signal on detector Di. This pulse charge signal is sent to the input terminal of the pre-processing circuit board Si via a signal cable and then to the i-th preamplifier. The i-th preamplifier amplifies the pulse charge signal from detector Di for the first time and outputs it to the summing circuit. The summing circuit superimposes the pulse charge signals from the i-th preamplifier and outputs them to the main amplifier. The main amplifier shapes and amplifies the pulse charge signal from the summing circuit a second time and outputs it to the multichannel amplifier. Finally, the signal is sent to the computer to obtain the total energy spectrum.

[0068] Example 1:

[0069] The electrode structure was simulated using the AC / DC electrostatic module in the finite element software Comsol Multiphysics. A planar electrode structure was adopted, and the detector size was 10×10×5mm. 3 Since cadmium zinc telluride (CZN) was not available in the material library, cadmium telluride (CdTe) was selected, and its dielectric constant was set to 10.6. During the calculation, it was assumed that the electrode and CZN were in ohmic contact. Because the electrode thickness was only 100 nm, it was ignored during modeling and mesh generation to avoid overly dense or incorrect meshing due to its small thickness. The electrode was treated as follows: working surfaces were added to the upper and lower surfaces of the CZN, and these working surfaces were considered electrodes. A voltage was applied to the working surfaces. Since the top surface was the anode and the bottom surface was the cathode, a voltage of 800 V was applied to the top surface, and a voltage of 0 V was applied to the bottom surface. The mesh generation method used in the calculation was automatic meshing with extra fineness. The two-dimensional data of the midsection was extracted and output in full-precision format.

[0070] like Figure 2 Figures (a) and (b) show the potential and electric field distributions of the internal cross-section of the planar cadmium zinc telluride detector. As can be seen from the figure, the potential and electric field between the anode and cathode are uniformly distributed. The change in potential corresponds to the change in the weighted potential field. It can be seen that under the action of the built-in electric field, electrons move towards the anode and holes move towards the cathode. Since the weighted potential is also uniformly distributed, i.e. linear, the weights of electrons and holes on the induced charge are equal. Since the mobility lifetime product of holes in CZT crystal is one to two orders of magnitude lower than that of electrons, the inability to completely collect holes leads to a large broadening of the full-energy peak.

[0071] Example 2:

[0072] The electrode structure was simulated using the AC / DC electrostatic module in the finite element software Comsol Multiphysics. A quasi-hemispherical electrode structure was adopted, and the detector size was 10×10×5mm. 3Since cadmium zinc telluride (CZN) was not available in the material library, cadmium telluride (CdTe) was selected, and its dielectric constant was set to 10.6. During the calculation, it was assumed that the electrode and CZN were in ohmic contact. Because the electrode thickness was only 100 nm, it was ignored during modeling and meshing to avoid overly dense or incorrect meshing due to its small thickness. The electrode was treated as follows: working surfaces were added to the entire sides and bottom of the CZN, and a working surface with a diameter of 1.6 mm was added to the top surface. These working surfaces were considered electrodes, and voltages were applied to them. Since the top surface was the anode (1.6 mm diameter) and the sides and bottom were the cathodes, a voltage of 800 V was applied to the top surface, while 0 V was applied to the sides and bottom. The meshing method used in the calculation was automatic meshing with a very fine setting. The mid-section 2D data was extracted and output in full-precision format.

[0073] like Figure 2 (c) and (d) show the potential and electric field distributions of the internal mid-section of the quasi-hemispherical cadmium zinc telluride detector. Figure 2 (c) The change in electric potential corresponds to the change in the weighted potential field. It can be seen that this structure has a significant optimization effect on the weighted potential field. The weighted potential changes slowly near the cathode, and the amount of induced charge generated by the drift of holes to the cathode is relatively small. However, the weighted potential changes rapidly at the anode, so the amount of induced charge generated by the drift of electrons to the anode is relatively large. Figure 2(d) shows the distribution of the electric field in the cadmium zinc telluride crystal at 800V. The electric field strength is weak near the cathode and increases sharply near the anode. At the contact point between the cadmium zinc telluride crystal and the electrode, the electric field strength is very large due to the abrupt change in potential. The strong electric field near the anode is conducive to the rapid collection of electrons drifting to the anode, while simultaneously causing holes generated near the anode to drift to the region of slow weighted potential at the cathode. Therefore, this electrode structure and size are very effective for achieving single-electron collection.

[0074] Comparison of Examples 1 and 2:

[0075] By comparing Examples 1 and 2, it can be found that the quasi-hemispherical electrode, with the top surface as the anode (1.6 mm in diameter) and the sides and bottom surface as the cathode, can achieve high-efficiency charge collection, improve operational reliability, and enhance the energy resolution of the detection.

[0076] (4) Detection of high-energy protons

[0077] like Figure 3 This is a schematic diagram of proton detection, which includes a detection system and a signal processing system. The detection system is a five-layer cadmium zinc telluride detector, and the signal processing system includes five preamplifiers, an summing circuit, a main amplifier circuit, a multichannel amplifier, and a computer.

[0078] When the incident proton enters the first layer of the zinc cadmium telluride detector, the energy deposited there is ΔE1, which generates a pulse charge signal on the detector D1. The pulse charge signal generated by the detector D1 is sent to the input terminal of the pre-processing circuit board S1 through the signal cable and enters the first preamplifier. The first preamplifier amplifies the pulse charge signal from the detector D1 for the first time and outputs it to the summing circuit.

[0079] When the incident proton enters the second layer of the zinc cadmium telluride detector, the energy deposited there is ΔE2, which generates a pulse charge signal on detector D2. The pulse charge signal generated by detector D2 is sent to the input terminal of the pre-processing circuit board S2 through the signal cable and enters the second preamplifier. The second preamplifier amplifies the pulse charge signal from detector D2 for the first time and outputs it to the summing circuit.

[0080] When the incident proton enters the third layer of the zinc cadmium telluride detector, the energy deposited there is ΔE3, which generates a pulse charge signal on detector D3. The pulse charge signal generated by detector D3 is sent to the input terminal of the pre-processing circuit board S3 through the signal cable and enters the third preamplifier. The third preamplifier amplifies the pulse charge signal from detector D3 for the first time and outputs it to the summing circuit.

[0081] When the incident proton enters the fourth layer of the zinc cadmium telluride detector, the energy deposited there is ΔE4, which generates a pulse charge signal on detector D4. The pulse charge signal generated by detector D4 is sent to the input terminal of the pre-processing circuit board S4 through the signal cable and enters the fourth preamplifier. The fourth preamplifier amplifies the pulse charge signal from detector D4 for the first time and outputs it to the summing circuit.

[0082] When the incident proton enters the fifth layer of the zinc cadmium telluride detector, the energy deposited there is ΔE5, which generates a pulse charge signal on detector D5. The pulse charge signal generated by detector D5 is sent to the input terminal of the pre-processing circuit board S5 through the signal cable and enters the fifth preamplifier. The fifth preamplifier amplifies the pulse charge signal from detector D5 for the first time and outputs it to the summing circuit.

[0083] The summing circuit superimposes the pulse charge signals from the first, second, third, fourth, and fifth preamplifiers and outputs them to the main amplifier. The main amplifier shapes and amplifies the pulse charge signals from the summing circuit and outputs them to the multichannel amplifier. Finally, the signals are sent to the computer to obtain the total energy spectrum.

[0084] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A design method for a high-energy proton detection probe based on stacked cadmium zinc telluride, characterized in that, The high-energy proton detection probe includes several detection units, an electrostatic shielding layer (1), a metal shell (16), a base (9), several preamplifier circuits, and an additive circuit. The metal shell 16 is open at both ends, with the electrostatic shielding layer (1) connected to the top and the base (9) located inside the bottom. Several detection units are placed horizontally inside the metal shell (16), and several preamplifier circuits are placed vertically. There is no contact between the detection units or between the preamplifier circuit units. The additive circuit is located inside the metal shell (16) and placed on the base (9). A Remer interface is located below the base (9), and the Remer interface is connected to the additive circuit via a cable. The preamplifier circuit is connected to the additive circuit. The detection unit is a zinc cadmium telluride detector, with a zinc cadmium telluride semiconductor substrate and a hemispherical gold electrode plated on the outside. One side of the plated circular electrode is the anode, and the other side and the surrounding area are the cathodes; the outer wall of the base (9) has a groove on the circumferential direction for holding the plastic shell (17) containing the probe, and the outer side has threads for threaded connection with the metal shell (16); the several detection units are fixed and supported by detection unit support frames, and the left and right ends of each layer of the cadmium zinc telluride detector are supported by a detection unit support frame on the top and bottom of each layer, and the several detection unit support frames are fixed on the plastic shell, and the plastic shell is fitted inside the groove of the base (9) for positioning and limitation; the number of detection units is 1, 2, ... n, and 5 ≤ n ≤ 10; the number of preamplifier circuits is 1, 2, ... m, and 5 ≤ m ≤ 10; the number of m and n is the same, and the detection units and preamplifier circuits are connected one-to-one; The design method includes the following steps: (1) Selection of electrostatic shielding layer material: Beryllium metal was selected as the electrostatic shielding material, with a surface resistivity of less than 1×10⁻⁶. 4 Ω / m 2 Or the volume resistivity does not exceed 1×10 3 Ω.cm, thickness selected as 200μm, density of 1.85g / cm³ 3 ; (2) Design of the substrate and size of the stacked cadmium zinc telluride detector: The thickness of each layer of cadmium zinc telluride detector is set to 1-5 mm; The calculation was performed using the TRIM module in the SRIM software package based on the Monte Carlo algorithm. The input consisted of an electrostatic shielding material with a thickness of 200 μm and several layers of cadmium zinc telluride (CZN) semiconductor material, where the CZN semiconductor density was 5.8 g / cm³. 3 With the Cd:Zn:Te ratio of 0.9:0.1:1, a preliminary simulation was performed to calculate the track of a 100 MeV proton in the stacked cadmium zinc telluride semiconductor, as well as the incident depth and ionization energy loss of the 100 MeV proton in the stacked cadmium zinc telluride semiconductor, so that the 100 MeV proton finally lands exactly in the last layer of cadmium zinc telluride detector material, thereby determining the number of layers of the stacked cadmium zinc telluride semiconductor; (3) Design of the electrode structure and dimensions of the stacked cadmium zinc telluride detector: The planar electrode structure and the quasi-hemispherical electrode structure were simulated using the AC / DC electrostatic module in the finite element software Comsol Multiphysics. The detector size was 10×10×5mm. 3 During the calculation, it is assumed that the electrode and cadmium zinc telluride are in ohmic contact. The electrode thickness is ignored when modeling and meshing. The electrode is treated as follows: a working surface is added at the electrode of cadmium zinc telluride. The working surface is regarded as the electrode. A voltage is applied to the working surface. The voltage applied to the anode is 800V and the voltage applied to the cathode is 0V. The meshing method used in the calculation is automatic meshing with special refinement. The electric field distribution and potential distribution data of the mid-section are extracted and output in full-precision format.

2. The design method of the high-energy proton detection probe based on stacked cadmium zinc telluride as described in claim 1, characterized in that, In step 3, a suitable electrode structure is determined based on the data of electric field distribution and electric potential distribution of the mid-section.

3. The design method of the high-energy proton detection probe based on stacked tellurium zinc cadmium as described in claim 1, characterized in that, In step 3, from the perspective of potential distribution, since the change in potential corresponds to the change in the weighted potential field, the more rapidly the weighted potential changes near the anode, the more the structure and size of the electrode meet the requirements. From the perspective of electric field distribution, the stronger the electric field near the anode, the more conducive it is to the rapid collection of electrons drifting to the vicinity of the anode, and at the same time, to the drift of holes generated near the anode to the region where the cathode has a slow potential. In this case, the structure and size of the electrode will better meet the requirements.

4. The design method of the high-energy proton detection probe based on stacked tellurium zinc cadmium as described in claim 1, characterized in that, The method to determine whether the overall cadmium zinc telluride detector meets the requirements is as follows: the Bragg curve is formed by the ionization energy loss; as the remaining range decreases, the specific ionization gradually increases, reaching a maximum value at the end of the remaining range - the Bragg peak; if the specific ionization increases at the front end and forms an obvious Bragg peak in the last layer of cadmium zinc telluride semiconductor, it indicates that the stacked detector structure meets the requirements.

5. A detection method for a high-energy proton detector probe of stacked tellurium zinc cadmium designed using the design method described in claim 1, characterized in that, Includes the following steps: Step 1: The incident proton enters the i-th layer of the cadmium zinc telluride detector, where the energy deposited is ∆Ei, which generates a pulse charge signal on the detector Di; Step 2: The pulse charge signal generated by the detector Di is sent to the input terminal of the pre-processing circuit board Si through the signal cable and enters the i-th preamplifier; Step 3: The i-th preamplifier amplifies the pulse charge signal from detector Di for the first time and outputs it to the summing circuit; Step 4: The summing circuit superimposes the pulse charge signals from the i-th preamplifier and outputs them to the main amplifier; Step 5: The main amplifier shapes and amplifies the pulse charge signal from the summing circuit, outputs it to the multichannel, and finally sends it to the computer to obtain the total spectrum.

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