Radiation dose measurement apparatus and radiation dose measurement method

Abstract

A radiation dose measurement apparatus (200) and a radiation dose measurement method. The radiation dose measurement apparatus (200) comprises: an ionization chamber (210), which defines an accommodating space (211), wherein the accommodating space (211) is filled with a gas, and the gas is configured to react with rays entering the accommodating space (211), so as to generate electrons; and N VDMOS devices (100), which are arranged in the accommodating space (211), wherein N is an integer greater than or equal to 1, a change occurs in a source-drain reverse current-voltage curve of at least one of the N VDMOS devices (100) in response to the electrons, and the radiation dose of the rays is obtained by means of the source-drain reverse current-voltage curves before and after the change.

Description

Radiation dose detection device and radiation dose detection method

[0001] This application claims priority to Chinese patent application No. 202311811466.5 filed on December 26, 2023, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present disclosure relates to the field of radiation measurement, and more particularly, to a radiation dose detection device and a radiation dose detection method. Background Art

[0003] Radiation dosimeters, as radiation dose detection devices, are widely used in fields such as nuclear physics, medicine, environmental monitoring, radiation protection, and aerospace. For example, in nuclear physics experiments, they can be used to measure the energy and trajectory of particles, thereby studying nuclear reactions and particle physics. In medicine, radiation dosimeters can be used to measure the activity and dose of radioactive isotopes, thereby conducting radiotherapy and diagnosis. In environmental monitoring, radiation dosimeters can be used to measure radioactive substances in the air, thereby assessing environmental radiation levels. In radiation protection, radiation dosimeters can be used to monitor radiation dose levels in the workplace and surrounding environment to protect workers and the public. In the aerospace field, radiation dosimeters can be used to detect radiation dose levels in the spacecraft environment.

[0004] In related technologies, TLD dosimeters are commonly used for personal and environmental dose measurement. TLDs are passive dosimeters based on thermoluminescence, measuring the dose absorbed by a person or object when exposed to ionizing radiation (such as X-rays and gamma rays). MOSFET-based radiation dosimeters can also be used, primarily using the change in the gate-source threshold voltage of the MOSFET after exposure to radiation to calibrate the exposure dose.

[0005] To elaborate, a TLD dosimeter consists of three main components: thermoluminescent material, an optical readout system, and a temperature control device. Thermoluminescent materials are typically crystals or glass containing dopants, such as LiF:Mg, Ti, etc. After being irradiated, the thermoluminescent material releases a light signal at a specific temperature. This material requires regular recycling, and consumables must be replaced quarterly. The testing and reading environment must be waterproof and moisture-proof, consuming a significant amount of manpower and material resources, and requiring the use of specialized equipment for reading. This makes operation complex and hinders management and system integration. MOSFET-based radiation dosimeters are often only used for high-dose situations, such as irradiation doses exceeding several Gy, and are essentially disposable. Even if they can be restored through annealing, their performance and dose linearity deteriorate, making them difficult to use for human radiation dose detection.

[0006] Therefore, in the process of realizing the inventive concept of the present disclosure, the inventors found that the relevant radiation dose measurement devices have defects such as high consumables cost, high operating skill requirements, harsh measurement environment, and poor measurement repeatability. Summary of the Invention

[0007] The present disclosure provides a radiation dose detection device and a radiation dose detection method.

[0008] One aspect of an embodiment of the present disclosure provides a radiation dose detection device, comprising: an ionization chamber defining a containment space, the containment space being filled with gas, the gas being configured to react with radiation entering the containment space to produce electrons; N VDMOS devices disposed in the containment space, where N is an integer greater than or equal to 1; wherein a source-drain reverse current-voltage curve of at least one of the N VDMOS devices changes in response to the electrons, and the radiation dose of the radiation is obtained by measuring the source-drain reverse current-voltage curve before and after the change.

[0009] According to an embodiment of the present disclosure, when the value of N is greater than or equal to 2, the gates of the N VDMOS devices are connected in a cascade manner.

[0010] According to an embodiment of the present disclosure, the device further includes: a conductive metal wire placed in the accommodation space, wherein the gates of N VDMOS devices are cascaded through the metal wire.

[0011] According to an embodiment of the present disclosure, the N VDMOS devices are configured to receive the electrons through the metal wire and the gate of each device, thereby causing a change in the source-drain reverse current-voltage curve of each VDMOS device.

[0012] According to an embodiment of the present disclosure, the N VDMOS devices include a main VDMOS device and N-1 auxiliary VDMOS devices; wherein the radiation dose of the ray is obtained through the source-drain reverse current-voltage curve before and after the change of the main VDMOS device.

[0013] According to an embodiment of the present disclosure, the drain and source of each auxiliary VDMOS device are short-circuited.

[0014] According to an embodiment of the present disclosure, when the value of N is 1, the electrons are received by the gate of a single VDMOS device, causing a change in the source-drain reverse current-voltage curve of the single VDMOS device.

[0015] According to an embodiment of the present disclosure, the gas includes a first working gas, which is configured to react with rays entering the accommodation space to produce electrons, and the rays include at least one of X-rays, α-rays, γ-rays, and β-rays; or, the gas includes a second working gas, which is configured to react with a neutron beam entering the accommodation space to produce electrons.

[0016] According to an embodiment of the present disclosure, the ionization chamber is configured to: coat at least one sidewall of the accommodation space with a neutron sensitive material layer, wherein the neutron sensitive material layer is configured to react with a neutron beam entering the accommodation space to generate electrons.

[0017] According to an embodiment of the present disclosure, the radiation dose of the ray is obtained by the source-drain reverse current-voltage curve before and after the change, including: determining at least one of the current change value, voltage change value, and breakdown voltage change value before and after irradiation through the source-drain reverse current-voltage curve before and after the change to obtain the radiation dose of the ray.

[0018] Another aspect of an embodiment of the present disclosure provides a radiation dose detection method, comprising: causing an ionization chamber to receive radiation to be detected, wherein the ionization chamber defines a receiving space, the receiving space is filled with gas, and the gas is configured to react with the radiation entering the receiving space to produce electrons; causing a source-drain reverse current-voltage curve of at least one device among N VDMOS devices to change in response to the electrons, wherein N of the VDMOS devices are placed in the receiving space, and N is an integer greater than or equal to 1; and obtaining the radiation dose of the radiation by using the source-drain reverse current-voltage curve before and after the change. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above contents and other objects, features and advantages of the present disclosure will become more apparent through the following description of the embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0020] FIG1 schematically shows a structural diagram of a VDMOS device according to an embodiment of the present disclosure;

[0021] FIG2 schematically shows a structural diagram of a radiation dose detection device according to an embodiment of the present disclosure;

[0022] FIG3 schematically shows a structural diagram of a radiation dose detection device according to another embodiment of the present disclosure;

[0023] FIG4 schematically shows a structural diagram of a radiation dose detection device according to another embodiment of the present disclosure;

[0024] FIG5 schematically shows a flow chart of a radiation dose detection method according to an embodiment of the present disclosure;

[0025] The reference numerals associated with the above drawings are as follows:

[0026] 100. VDMOS device; 200. Radiation detection device; 210. Ionization chamber; 211. Accommodation space.

[0027] It should be noted that, for the sake of clarity, in the drawings used to describe the embodiments of the present disclosure, the sizes of the overall / local structures or overall / local areas may be enlarged or reduced, that is, these drawings are not drawn according to the actual scale. DETAILED DESCRIPTION

[0028] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and are not intended to limit the scope of the present disclosure. In the detailed description below, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments of the present disclosure. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present disclosure.

[0029] First, some of the terms involved in this disclosure are defined as follows:

[0030] TLD: Thermo Luminescence Dosimeter, thermoluminescence dosimeter;

[0031] MOSFET: Metal-Oxide-Semiconductor Field Effect Transistor, metal oxide semiconductor field effect transistor;

[0032] VDMOS: Vertical Double Diffusion Metal Oxide Semiconductor, vertical double diffused metal oxide semiconductor transistor;

[0033] Source-drain reverse current-voltage curve: Affected by the source-drain reverse IV characteristics, the curve represents the trend of the current between the source and the drain as the voltage between the source and the drain changes;

[0034] Breakdown Voltage: The voltage at which the body diode between the drain and source undergoes avalanche breakdown. When the gate voltage is 0, the drain-source channel is pinched off. When the current provided between the drain and source can continuously increase the reverse bias electric field of the body diode, avalanche breakdown occurs.

[0035] IDS: Usually after turning off the power semiconductor device, a voltage is provided to the drain, and then the current value between the drain and the source is measured.

[0036] The disclosed embodiments provide a radiation dose detection device and method that combine ionization chamber and VDMOS technology. Leveraging the low-dose sensitivity of the ionization chamber and VDMOS devices, they facilitate low-dose (e.g., uSv) dose detection, eliminating the need for frequent VDMOS device replacement and providing high adaptability to various measurement environments. Furthermore, the ionization chamber and VDMOS technology can directly output electrical signals, making them easily integrated with electronic hardware to generate source-drain reverse current-voltage curves for direct reading of radiation dose. This reduces operational skill requirements and improves measurement repeatability.

[0037] The following describes the technical solutions of the radiation dose detection device and the radiation dose detection method in the embodiments of the present disclosure with reference to FIG1 to FIG4 .

[0038] FIG1 schematically shows a structural diagram of a VDMOS device according to an embodiment of the present disclosure.

[0039] Figure 1 shows a VDMOS device 100 with a vertically conductive double-diffused structure. VDMOS device 100 utilizes a double diffusion structure, with P-type and N-type regions diffused sequentially in an N- epitaxial layer on an N+ substrate. The source S and gate G are then extended from the top surface, along with a SiO2 oxide layer. The drain D extends from the back of the N+ substrate. The P region between the N+ and N- regions forms a channel, connecting the channels and preventing punch-through between the drain and source.

[0040] Continuing with Figure 1 , the operating principle of the VDMOS device 100 is as follows: When a power supply voltage UDS is applied between the source S and drain D, and the gate G potential is zero or negative, the PN junction is reverse biased, resulting in no current flowing between the source S and drain D, i.e., IDS = 0. When a positive voltage is applied to the gate G, electrons are induced in the P- region and accumulate, forming an N-channel. The N-channel connects the upper N+ region with the lower N- region, generating a current IDS between the source S and drain D. The magnitude of this current depends on the magnitude of the positive voltage applied to the gate G.

[0041] It should be noted that FIG1 shows an exemplary VDMOS device 100 structure, but the present disclosure is not limited thereto. Planar VDMOS devices, vertical VDMOS devices or VDMOS devices of other structures may also be applicable to the radiation dose detection device proposed in the present disclosure.

[0042] The radiation dose detection device 200 provided in an embodiment of the present disclosure is described below.

[0043] FIG2 schematically shows a structural diagram of a radiation dose detection device 200 according to an embodiment of the present disclosure.

[0044] In some embodiments, as shown in FIG2 , a radiation dose detection device 200 may include an ionization chamber 210 and N VDMOS devices 100. The ionization chamber 210 defines a receiving space 211 filled with a gas configured to react with radiation entering the receiving space 211 to generate electrons. The N VDMOS devices 100 are placed in the receiving space 211, where N is an integer greater than or equal to 1. The source-drain reverse current-voltage curve of at least one of the N VDMOS devices 100 changes in response to the electrons, and the radiation dose of the radiation is determined by the source-drain reverse current-voltage curve before and after the change.

[0045] Radiation dose refers to the amount of radiation energy received by a person or object. Radiation dose can come from natural radiation, artificial radiation sources, nuclear facility accidents, or nuclear war, and in any case, it will have varying degrees of impact on the human body.

[0046] Illustratively, the ionization chamber 210 is an instrument for measuring radiation. It uses the charged particles produced when radiation interacts with matter to measure the energy and intensity of the radiation. The ionization chamber 210 typically includes a metal housing and an ionization chamber 210 gas chamber (i.e., a containing space 211) within the housing. The ionization chamber 210 gas chamber is filled with gas. When radiation impinges on the gas, the atoms or molecules in the gas are ionized, generating free electrons and positive ions.

[0047] For example, when radiation particles pass through the gas in the ionization chamber 210, they interact with gas atoms or molecules, thereby generating ionization, which produces free electrons and positive ion pairs. Since the electron drift velocity is 2-3 orders of magnitude faster than that of ionized ions, the electrons will quickly move to the gate G of the VDMOS device 100, thereby changing the charge of the gate G, affecting the reverse characteristics between the drain and source electrodes, and causing the source-drain reverse IV characteristics of the VDMOS device 100 to change significantly. The radiation dose can be calibrated by the source-drain reverse current-voltage curve before and after the change, thereby realizing radiation dose detection. Furthermore, it can be effective for low doses and can realize uSv-level radiation dose detection.

[0048] In some embodiments, the gas includes a first working gas configured to react with radiation entering the containment space 211 to generate electrons. The radiation includes at least one of X-rays, alpha rays, gamma rays, and beta rays. For example, the first working gas includes air, an inert gas, or one or more gases such as He, Ne, Ar, Kr, Xe, or air. The containment space 211 can be a confined space. For example, the gas within the confined space can react with one or more radiations (such as at least one of X-rays, alpha rays, gamma rays, and beta rays) to generate ionization effects and generate electrons.

[0049] In other embodiments, the gas includes a second working gas, which is configured to react with the neutron beam entering the containment space 211 to generate electrons. And / or the ionization chamber 210 is configured to coat at least one sidewall of the containment space 211 with a neutron-sensitive material layer, wherein the neutron-sensitive material layer is configured to react with the neutron beam entering the containment space 211 to generate electrons.

[0050] For example, gases such as helium (He3) and boron trifluoride (BF3) can be used as the second working gas, which react with the neutron beam to produce charged particles. Boron (B), lithium (Li), gadolinium (Gd), and uranium 235 (U235) can be applied as a neutron-sensitive material layer. These react with the neutron beam to produce charged particles, achieving the same ionization effect, thereby detecting the neutron beam and expanding its application scenarios.

[0051] It is understandable that the scope of protection of the present disclosure is not limited to X-rays, α-rays, γ-rays, β-rays and neutron beams. On the basis of adopting the inventive concept of the present disclosure to combine the ionization chamber and VDMOS technology to realize radiation dose detection, the corresponding type of gas that reacts to produce electrons for the detected rays can be filled in the accommodation space, or the corresponding type of material that reacts to produce electrons can be coated on the side wall of the accommodation space.

[0052] The type of device encapsulated within the ionization chamber 210 to implement the radiation dose detection function is a key factor affecting the performance of the radiation dose detection device 200. According to the embodiments of the present disclosure, the ionization chamber 210 and VDMOS technology are combined, and the low-dose sensitivity of the ionization chamber 210 is utilized to conveniently implement low-dose dose detection (e.g., on the order of uSv), eliminating the need for frequent replacement of the VDMOS device 100 and providing high adaptability to various measurement and reading environments. Furthermore, the ionization chamber 210 and VDMOS technology can directly output electrical signals, making it easy to combine with electronic hardware to obtain a source-drain reverse current-voltage curve to directly read the radiation dose, reducing operational skill requirements and improving measurement and reading repeatability.

[0053] In some embodiments, the radiation dose of the ray is obtained by the source-drain reverse current-voltage curve before and after the change, including: determining at least one of the current change value, voltage change value, and breakdown voltage change value before and after irradiation through the source-drain reverse current-voltage curve before and after the change to obtain the radiation dose of the ray.

[0054] For example, the corresponding relationship between the radiation dose of the emitted ray and at least one of the current change value, voltage change value, and breakdown voltage change value before and after irradiation is determined, and the radiation dose value of the ray to be measured is obtained through at least one of the current, voltage, and breakdown voltage.

[0055] According to the embodiments of the present disclosure, the changes in at least one of the current, voltage and breakdown voltage caused by rays of different radiation doses can be considered, and the radiation dose of the rays can be tested, which can improve the convenience and accuracy of detection.

[0056] FIG3 schematically shows a structural diagram of a radiation dose detection device 200 according to another embodiment of the present disclosure.

[0057] As shown in FIG. 3 , when the value of N is 1, electrons are received through the gate of a single VDMOS device 100 , causing a change in the source-drain reverse current-voltage curve of the single VDMOS device 100 .

[0058] For example, referring to FIG3 , a single VDMOS device 100 can be packaged in an ionization chamber 210 formed of a metal shell. The shell defines a closed receiving space 211 filled with gas, enabling radiation dose detection. For example, when the radiation dose detection device 200 is exposed to X-rays (i.e., X-rays in FIG3 , for example only) in a radiation field, when the radiation particles pass through the gas in the ionization chamber 210, they interact with gas atoms or molecules, resulting in ionization. Electrons quickly move to the gate of the single VDMOS device 100, thereby changing the gate charge and affecting the reverse characteristics between the drain and source electrodes, causing a significant change in the source-drain reverse IV characteristics of the VDMOS. By detecting the change in at least one of the current, voltage, and breakdown voltage on the reverse IV curve before and after exposure, the radiation dose can be calibrated.

[0059] According to the embodiments of the present disclosure, by packaging a single VDMOS device 100 in the ionization chamber 210 , the radiation dose range that can be detected by the single VDMOS device 100 can be accurately detected with low cost.

[0060] FIG4 schematically shows a structural diagram of a radiation dose detection device 200 according to another embodiment of the present disclosure.

[0061] In some embodiments, when the value of N is greater than or equal to 2, the gates of N VDMOS devices 100 are connected in cascade. Referring to FIG. 4 , which illustrates an example of two VDMOS devices 100 connected together, it will be appreciated that more than two VDMOS devices 100 can also be connected together. When the gates of N VDMOS devices 100 are connected in cascade to form a charge collection region (as shown in the dashed box in FIG. 2 ), high gain can be achieved. The cascade connection increases the gate area, thereby raising the upper limit of radiation dose detection.

[0062] In some embodiments, the radiation dose detection device 200 may further include a conductive metal wire disposed within the accommodation space 211. The metal wire connects the gates of the N VDMOS devices 100. In some embodiments, the N VDMOS devices 100 are configured to receive electrons through the metal wire and the gates of each device, thereby causing a change in the source-drain reverse current-voltage curve of each VDMOS device 100.

[0063] Referring to Figure 4 , two VDMOS devices 100 are encapsulated within a metal-shell ionization chamber 210, which is filled with gas to enable radiation dose detection. When radiation particles pass through the working gas in ionization chamber 210, the ionized electrons quickly migrate through the metal wires to the gates of each VDMOS device 100, or directly contact the gates. This alters the gate charge, affecting the reverse characteristics between the drain and source electrodes and significantly changing the VDMOS's source-drain reverse IV characteristics.

[0064] According to an embodiment of the present disclosure, the gates of two VDMOS devices 100 are cascaded through a metal wire, and the gates of each VDMOS device 100 and the metal wire can be combined to receive electrons, further increasing the area for detecting electrons and improving collection efficiency and detection sensitivity.

[0065] In some embodiments, the N VDMOS devices 100 include a main VDMOS device 100 and N-1 auxiliary VDMOS devices 100 ; wherein the radiation dose is obtained by the source-drain reverse current-voltage curve before and after the change of the main VDMOS device 100 .

[0066] According to the embodiment of the present disclosure, when implementing radiation dose detection, one of the VDMOS devices 100 serves as the main detection device, and the others serve as auxiliary detection devices. The auxiliary detection devices can be used to increase the gate area and increase the upper limit of radiation dose detection.

[0067] In some embodiments, the drain and source of each auxiliary VDMOS device 100 are short-circuited. Continuing with FIG4 , since the gate of the auxiliary VDMOS device 100 can be used to increase the total gate area of ​​the radiation dose detection apparatus 200 , the short-circuited source and drain of the auxiliary VDMOS device 100 can reduce the influence of the source and drain, thereby preventing it from affecting the radiation dose detection results.

[0068] In some embodiments, the ionization chamber 210 may define multiple volumes, and the detection configuration within any one volume may be different from the detection configuration within at least one other volume. For example, the detection configuration may include at least one of the following: the type of gas, the number of VDMOS devices 100, and whether the sidewalls are coated with a neutron-sensitive material layer.

[0069] For example, a shielding layer can be added to the sidewalls of each volume, and a shielding area that can be opened or closed can be reserved to allow or prohibit the entry of radiation / neutron beams into that volume. This allows for multiple detection configurations within the same radiation dose detection device 200, thereby adapting to different detection requirements. For example, some volumes can be filled with a first working gas, while others can be filled with a second working gas. With the shielding area being openable or closed, the detection of X-rays or neutron beams can be switched. For another example, if different volumes are packaged with different numbers of VDMOS devices 100, different ranges of radiation doses can be detected.

[0070] In other embodiments, multiple volumes may be defined within the ionization chamber 210, wherein one volume encapsulates one or more VDMOS devices 100 without being filled with gas, and at least two other volumes are filled with different gases or coated with a neutron-sensitive material layer without encapsulating the VDMOS devices 100, and the other two volumes share the volume encapsulating the one or more VDMOS devices 100.

[0071] For example, three enclosed volumes are defined within the ionization chamber 210. Volume A encapsulates five VDMOS devices 100, volume B is filled with air for detecting radiation, and volume C is filled with boron trifluoride for detecting neutron beams. Shielding layers can be added to the side walls of volumes B and C, and shielded areas that can be opened or closed are reserved to allow or prohibit radiation / neutron beams from entering the volumes.

[0072] For example, volume B and volume A share a conductive sidewall, while volume C and volume A share another conductive sidewall. During radiation detection, the shielding area of ​​volume B is open, while the shielding area of ​​volume C is closed. Radiation entering volume B ionizes the air, generating electrons. These electrons are then conducted to the conductive sidewall, which is connected to a metal wire. The metal wire then conducts the electrons to the gates of each VDMOS device 100, thereby determining the radiation dose based on the source-drain reverse current-voltage curve of the primary VDMOS device 100. Neutron beam detection is similar to radiation detection and will not be further elaborated here.

[0073] For another example, volume B and volume A share a sidewall that can be opened or closed, and volume C and volume A share another sidewall that can be opened or closed. For example, when detecting radiation, the shielding area of ​​volume B is opened, the shielding area of ​​volume C is closed, and in volume A, only the sidewall shared with volume B is opened. After radiation enters volume B, it ionizes the air and generates electrons. These electrons are then conducted to the gates of each VDMOS device 100 in volume A. The radiation dose is then determined based on the source-drain reverse current-voltage curve of the primary VDMOS device 100. The gas that entered volume A can then be extracted. Detecting a neutron beam is similar to detecting radiation and will not be further elaborated here.

[0074] In combination with the above-mentioned device embodiment, the present disclosure further provides a radiation dose detection method, which is described below with reference to FIG5 .

[0075] FIG5 schematically shows a flow chart of a radiation dose detection method according to an embodiment of the present disclosure.

[0076] As shown in FIG5 , the radiation dose detection method of this embodiment includes:

[0077] In operation S510 , the ionization chamber 210 receives radiation to be detected, wherein the ionization chamber 210 defines a receiving space 211 , the receiving space 211 is filled with gas, and the gas is configured to react with the radiation entering the receiving space 211 to generate electrons;

[0078] In operation S520, a source-drain reverse current-voltage curve of at least one of the N VDMOS devices 100 is changed in response to electrons, wherein the N VDMOS devices 100 are placed in the accommodation space 211, and N is an integer greater than or equal to 1;

[0079] In operation S530, the radiation dose is obtained by determining the source-drain reverse current-voltage curve before and after the change. For example, the radiation dose is obtained by determining at least one of a current change value, a voltage change value, and a breakdown voltage change value before and after the exposure based on the source-drain reverse current-voltage curve before and after the change.

[0080] In some embodiments, more than two VDMOS devices 100 are packaged into the accommodation space 211 , and the gates of the more than two VDMOS devices 100 are connected in a cascade manner.

[0081] In some embodiments, when N is greater than or equal to 2, the gates of N VDMOS devices 100 are cascaded via a metal wire, wherein the metal wire is conductive and disposed within the receiving space 211. In some embodiments, electrons are received through the metal wire and the gates of each device, causing a change in the source-drain reverse current-voltage curve of each VDMOS device 100.

[0082] In some embodiments, a main VDMOS device 100 is determined from N VDMOS devices 100 , and N−1 auxiliary VDMOS devices 100 are determined; wherein the radiation dose is obtained based on the source-drain reverse current-voltage curve before and after the change of the main VDMOS device 100 .

[0083] In some embodiments, the drain and source of each auxiliary VDMOS device 100 are shorted.

[0084] In some embodiments, when the value of N is 1, electrons are received through the gate of a single VDMOS device 100 , causing a change in the source-drain reverse current-voltage curve of the single VDMOS device 100 .

[0085] In some embodiments, a neutron sensitive material layer is coated on at least one sidewall of the accommodation space 211 , wherein the neutron sensitive material layer is configured to react with a neutron beam entering the accommodation space 211 to generate electrons.

[0086] In some embodiments, multiple volumes are defined within the ionization chamber 210 such that a detection configuration within any one volume is different from a detection configuration within at least one other volume.

[0087] In some embodiments, multiple volumes are defined within the ionization chamber 210, wherein one volume encapsulates one or more VDMOS devices 100 without being filled with a gas. At least two other volumes are filled with different gases or coated with a neutron-sensitive material layer without encapsulating the VDMOS devices 100, and share the volume encapsulating the one or more VDMOS devices 100.

[0088] With reference to the above-mentioned embodiments and Figures 1 to 5, the radiation dose detection device 200 and the radiation dose detection method provided by the present disclosure utilize the high sensitivity of the ionization chamber 210 and encapsulate the VDMOS into the ionization chamber 210. The basic structure of the radiation dose detection device 200 is composed of one or more VDMOS cascades to form a charge collection area, wherein multiple VDMOS cascades are connected by metal wires to cascade multiple VDMOS gates to improve the collection efficiency. A metal shell ionization chamber 210 is surrounded by the periphery of the radiation dose detection device 200, and a gas (usually air, inert gas, etc.) is filled between the VDMOS and the shell. Neutron detection can be achieved by changing the gas filled in the shell (He gas, etc.) or coating the inner side of the shell with a neutron-sensitive material layer (such as B, Li and Gd, etc.).

[0089] According to the embodiments of the present disclosure, by combining the ionization chamber and VDMOS technology, low-dose (uSv level) dose detection can be achieved. Compared with traditional TLD technology, the radiation dosimeter using the ionization chamber and VDMOS technology directly outputs electrical signals, which is easy to combine with electronic hardware to achieve miniaturization and systematization, reducing the number of dedicated thermoluminescent radiation dose detection systems.

[0090] Moreover, compared with TLD technology, it has obvious technical advantages in terms of consumables (TLD needs to be recycled and replaced every quarter), operating skill requirements (real-time direct reading through wireless Bluetooth and data reading terminal), measurement and reading environment (TLD test and reading environment requires waterproof and moisture-proof), measurement and reading repeatability (it can be reused more than a hundred times), zeroing method (directly reset through electronic hardware), dose measurement upper limit (its dose detection upper limit can be extended to 10Sv through multiple VDMOS cascades), energy range lower limit (combined with the low-dose sensitivity of the ionization chamber, the lower limit monitors μSv), etc., and it can be a self-powered detector that does not require a power battery. For example, the ionization chamber combined with the VDMOS radiation detector itself does not need power to complete dose monitoring, which has obvious practical advantages over the current traditional TLD dosimeters and MOSFET-based radiation dosimeters.

[0091] Those skilled in the art will appreciate that the features described in the various embodiments and / or claims of this disclosure may be combined and / or coupled in various ways, even if such combinations and / or couplings are not explicitly described in this disclosure. In particular, the features described in the various embodiments and / or claims of this disclosure may be combined and / or coupled in various ways without departing from the spirit and teachings of this disclosure. All such combinations and / or couplings are intended to fall within the scope of this disclosure.

[0092] The embodiments of the present disclosure are described above. However, these embodiments are for illustrative purposes only and are not intended to limit the scope of the present disclosure. Although each embodiment has been described separately above, this does not mean that the measures in each embodiment cannot be used in combination to advantage. The scope of the present disclosure is defined by the appended claims and their equivalents. Without departing from the scope of the present disclosure, those skilled in the art may make various substitutions and modifications, which should all fall within the scope of the present disclosure.

Claims

1. A radiation dose detection device, comprising: An ionization chamber that defines an accommodation space filled with a gas configured to react with radiation entering the accommodation space to generate electrons; N VDMOS devices placed in the accommodation space, where N is an integer greater than or equal to 1; Wherein, the source-drain reverse current voltage curve of at least one of the N VDMOS devices changes in response to the electrons, and the radiation dose of the radiation is obtained from the source-drain reverse current voltage curves before and after the change.

2. The device according to claim 1, wherein, When the value of N is greater than or equal to 2, the gates of the N VDMOS devices are connected in a cascaded manner.

3. The device according to claim 2, wherein, The device further comprises: A conductive metal wire placed in the accommodation space, wherein the gates of the N VDMOS devices are cascaded through the metal wire.

4. The device according to claim 3, wherein, The N VDMOS devices are configured to receive the electrons through the metal wire and the gates of each device, thereby causing a change in the source-drain reverse current voltage curve of each VDMOS device.

5. The device according to claim 3, wherein, The N VDMOS devices include a main VDMOS device and N - 1 auxiliary VDMOS devices; Wherein, the radiation dose of the radiation is obtained from the source-drain reverse current voltage curves before and after the change of the main VDMOS device.

6. The device according to claim 5, wherein, The drain and source of each auxiliary VDMOS device are short-connected.

7. The device according to claim 1, wherein, When the value of N is 1, the electrons are received through the gate of the single VDMOS device, thereby causing a change in the source-drain reverse current voltage curve of the single VDMOS device.

8. The device according to claim 1, wherein, The gas includes a first working gas configured to react with radiation entering the accommodation space to generate electrons, and the radiation includes at least one of X-rays, α-rays, γ-rays, and β-rays; or, The gas includes a second working gas configured to react with a neutron beam entering the accommodation space to generate electrons.

9. The apparatus according to claim 1 or 8, wherein, The ionization chamber is configured to: Coat at least one side wall of the accommodation space with a neutron-sensitive material layer, where the neutron-sensitive material layer is configured to react with a neutron beam entering the accommodation space to generate electrons.

10. The device according to claim 1, wherein, The obtaining of the radiation dose of the radiation from the source-drain reverse current voltage curves before and after the change includes: Determining at least one of the current change value, voltage change value, and change value of the breakdown voltage before and after irradiation through the source-drain reverse current voltage curves before and after the change to obtain the radiation dose of the radiation.

11. A radiation dose detection method, comprising: Causing an ionization chamber to receive the radiation to be detected, where the ionization chamber defines an accommodation space filled with a gas configured to react with the radiation entering the accommodation space to generate electrons; Cause the source-drain reverse current voltage curve of at least one of the N VDMOS devices to change in response to the electrons, where the N VDMOS devices are placed in the accommodation space and N is an integer greater than or equal to 1; Obtain the radiation dose of the ray from the source-drain reverse current voltage curves before and after the change.

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