Silicon drift type radiation detector and radiation detection device

Abstract

The present invention provides a silicon drift type radiation detection element, a silicon drift type radiation detector and a radiation detection device, which improve the detection efficiency of radiation and the detection sensitivity of low energy radiation. The silicon drift type radiation detector (1) comprises a housing (13, 14) and a silicon drift type radiation detection element (11) arranged inside the housing (13, 14). The housing (13, 14) has an opening (131) that is not blocked. The silicon drift type radiation detection element (11) has a surface (111) opposite to the opening (131), and a light shielding film (161) is provided on the surface (111).

Description

Technical Field

[0001] The present invention relates to a silicon drift type radiation detection element, a silicon drift type radiation detector and a radiation detection device. Background Art

[0002] Among radiation detectors that detect radiation such as X-rays, there are radiation detectors that include radiation detection elements that use semiconductors. Among radiation detection elements that use semiconductors, there are, for example, silicon drift-type radiation detection elements. A radiation detector that includes a silicon drift-type radiation detection element is a silicon drift-type radiation detector (SDD: Silicon Drift Detector). In the past, in order to reduce noise, such radiation detection elements were cooled before use. The radiation detector includes a housing, a radiation detection element, and a cooling unit such as a Peltier element. The radiation detection element and the cooling unit are arranged on the inner side of the housing. In order to prevent condensation caused by cooling, the housing is made airtight, and the inner side of the housing is depressurized or sealed with dry gas. In addition, the radiation detection element is thermally isolated from the housing as much as possible.

[0003] The housing is provided with a window having a window member formed of a material that allows radiation to pass through. The radiation that passes through the window member enters the radiation detection element, and the radiation is detected. The window member has a light shielding function to prevent light from entering the radiation detection element. In addition, the window member needs to have a structural strength for maintaining an airtight state. An example of a radiation detector is disclosed in Patent Document 1.

[0004] Patent Document 1: Japanese Patent Publication No. 2000-55839

[0005] In order to improve the detection efficiency of radiation generated from the sample, it is sufficient to bring the radiation detection element close to the sample. However, in the conventional radiation detector, in order to maintain the airtight state of the shell, the shell and the window member need to be of a certain size, and the overall size of the radiation detector becomes larger. Due to the overall size of the radiation detector, there is a lower limit to the distance that the radiation detection element can be brought close to the sample, and there is a limit to the improvement of the detection efficiency.

[0006] In addition, in order to maintain an airtight state, the window member needs to have a certain degree of thickness. Due to the thickness of the window member, the transmittance of low-energy radiation through the window member becomes low, and low-energy radiation is difficult to enter the radiation detection element. Therefore, this radiation detector has low detection sensitivity to low-energy radiation. Summary of the invention

[0007] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a silicon drift type radiation detection element, a silicon drift type radiation detector, and a radiation detection device which improve the detection efficiency of radiation and the detection sensitivity of low energy radiation.

[0008] The silicon drift type radiation detection element of the present invention is characterized in that a light shielding film is provided on the surface on which radiation is incident.

[0009] In the present invention, a light shielding film is provided on the surface of the silicon drift type radiation detection element on which radiation is incident. The light shielding film prevents the generation of noise due to light, and the silicon drift type radiation detection element can operate.

[0010] The silicon drift type radiation detection element of the present invention is characterized in that the light shielding film reduces the amount of light incident on the surface to less than 0.1%.

[0011] In the present invention, the light-shielding film reduces the amount of light to less than 0.1%, thereby effectively preventing the generation of noise.

[0012] The silicon drift type radiation detection element of the present invention is characterized in that the light shielding film is a metal film having a thickness exceeding 50 nm and less than 500 nm.

[0013] In the present invention, a metal film having a thickness exceeding 50 nm and less than 500 nm is used as a light-shielding film, thereby obtaining a necessary and sufficient light-shielding property.

[0014] The silicon drift type radiation detection element of the present invention is characterized in that the light shielding film is a carbon film.

[0015] In the present invention, light shielding properties can be obtained by using the carbon film as a light shielding film.

[0016] The silicon drift-type radiation detection element of the present invention is characterized in that it also includes: a signal output electrode, which is arranged on the back side opposite to the surface, into which charges generated by the incidence of radiation flow and outputs a signal corresponding to the charges; a first electrode, which is arranged on the surface and to which a voltage is applied; and a plurality of second electrodes, which are arranged on the back side and surround the signal output electrode, and have different distances from the signal output electrode, the second electrode having a shape in which the length along one direction of the back side is greater than the length along other directions of the back side, and the signal output electrode is composed of a plurality of electrodes arranged along the one direction and connected to each other.

[0017] In one embodiment of the present invention, a silicon drift type radiation detection element includes: a signal output electrode disposed on the back; a first electrode disposed on the surface; and a plurality of second electrodes disposed on the back and surrounding the signal output electrode. The second electrode applies a voltage in a manner that generates a potential gradient in which the potential changes toward the signal output electrode. The second electrode has a shape in which the length in one direction is greater than the length in other directions, and the signal output electrode is composed of a plurality of electrodes arranged along the one direction. The plurality of electrodes are connected to each other. The increase in the area of ​​the signal output electrode is suppressed, and the change in the distance between the signal output electrode and the second electrode is small, and the deviation in the speed at which the charge is collected to the signal output electrode is small.

[0018] The silicon drift-type radiation detection element of the present invention is characterized in that it also includes: a signal output electrode, which is arranged on the back side opposite to the surface, into which charges generated by the incidence of radiation flow and outputs a signal corresponding to the charges; a first electrode, which is arranged on the surface and to which a voltage is applied; and a plurality of second electrodes, which are arranged on the back side and surround the signal output electrode, and have different distances from the signal output electrode, the second electrodes having a shape in which the length along one direction of the back side is greater than the length along other directions of the back side, and the signal output electrode includes a conductive wire arranged on the back side and extending along the one direction.

[0019] In one embodiment of the present invention, the second electrode has a shape in which the length in one direction is greater than the length in other directions, and the signal output electrode includes a conductive line extending along the one direction. The increase in the area of ​​the signal output electrode is suppressed, and the change in the distance between the signal output electrode including the conductive line and the second electrode is small, and the deviation in the speed at which charges are collected to the signal output electrode is small.

[0020] The silicon drift type radiation detector of the present invention comprises a shell having an unblocked opening and a silicon drift type radiation detection element of the present invention arranged inside the shell, wherein the shell has a surface opposite to the opening and a light shielding film is provided on the surface.

[0021] In the present invention, the housing of the silicon drift type radiation detector has an opening, and a light shielding film is provided on the surface of the incident radiation of the silicon drift type radiation detection element. The light shielding film prevents the generation of noise caused by light, and the silicon drift type radiation detection element can operate. Therefore, it is not necessary to provide a window having a window member in the opening for light shielding, and the opening is not blocked. Since the silicon drift type radiation detector has a window, even low-energy radiation can easily enter the silicon drift type radiation detection element. In addition, the size of the silicon drift type radiation detector becomes small.

[0022] In the silicon drift type radiation detector of the present invention, the surface is larger than the opening, the housing has an overlapping portion including an edge of the opening and overlapping with a portion of the surface, and a portion of the surface surrounded by the overlapping portion is covered by the light shielding film.

[0023] In the present invention, a portion of the housing overlaps a portion of the surface of the silicon drift type radiation detection element, and a portion of the surface surrounded by the overlapping portion of the housing is covered by a light shielding film. The portion of the silicon drift type radiation detection element into which radiation is incident is shielded, thereby preventing the generation of noise caused by light. The silicon drift type radiation detector can be used in an environment where visible light is incident inside.

[0024] The silicon drift type radiation detector of the present invention is characterized in that it does not include a cooling unit for cooling the silicon drift type radiation detection element, and the housing is not airtight.

[0025] In the present invention, the silicon drift type radiation detector does not include a cooling unit such as a Peltier element for cooling the silicon drift type radiation detection element. In recent years, due to the reduction of noise in circuits, etc., the silicon drift type radiation detector can obtain sufficient performance even without cooling. Since cooling is not performed, the housing does not need to be airtight. Therefore, the housing can be reduced in size, and the size of the silicon drift type radiation detector becomes smaller.

[0026] The silicon drift type radiation detector of the present invention is characterized in that no window member is provided at a position facing the surface.

[0027] In the present invention, a window member is not provided at a position of the silicon drift type radiation detection element facing the surface of the incident radiation. Since the radiation does not pass through the window member, even low energy radiation is more likely to enter the silicon drift type radiation detection element. In addition, the size of the silicon drift type radiation detector is reduced.

[0028] The silicon drift type radiation detector of the present invention further includes a filler that fills a gap between the housing and the silicon drift type radiation detection element.

[0029] In one embodiment of the present invention, a filler such as resin is filled between the housing and the silicon drift type radiation detection element. The bonding wires connected to the silicon drift type radiation detection element are buried in the filler to protect the bonding wires from moisture.

[0030] The radiation detection device of the present invention is characterized by comprising the silicon drift type radiation detector of the present invention and a spectrum generating unit that generates a spectrum of radiation detected by the silicon drift type radiation detector.

[0031] The radiation detection device of the present invention is characterized in that it includes: an irradiation unit, which irradiates radiation to a sample; a silicon drift-type radiation detector of the present invention, which detects radiation generated from the sample; a spectrum generating unit, which generates a spectrum of the radiation detected by the silicon drift-type radiation detector; and a display unit, which displays the spectrum generated by the spectrum generating unit.

[0032] In the present invention, since the silicon drift type radiation detector is small in size, it is possible to bring the silicon drift type radiation detector close to the sample in the radiation detection device. By bringing the silicon drift type radiation detector close to the sample, the detection efficiency of radiation generated from the sample is improved. In addition, even low-energy radiation is more likely to enter the silicon drift type radiation detection element, and the detection sensitivity of low-energy radiation is improved. Therefore, in the radiation detection device, the analysis of light elements becomes easy.

[0033] In the present invention, since even low-energy radiation is easily incident on the silicon drift type radiation detection element, the detection sensitivity of low-energy radiation is improved. In addition, by placing the silicon drift type radiation detector close to the sample, the present invention has excellent effects such as improving the detection efficiency of radiation generated from the sample. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a schematic cross-sectional view showing a configuration example of the radiation detector according to the first embodiment.

[0035] Figure 2 This is a block diagram showing the configuration of the radiation detection apparatus according to the first embodiment.

[0036] Figure 3 This is a schematic cross-sectional view showing a part of the radiation detection element and the cover according to the first embodiment.

[0037] Figure 4 It is a schematic cross-sectional view showing an example of a light-shielding film.

[0038] Figure 5 It is a schematic cross-sectional view showing another example of the light-shielding film.

[0039] Figure 6 This is a schematic cross-sectional view of another structural example of the radiation detector according to the first embodiment.

[0040] Figure 7 This is a schematic cross-sectional view showing a configuration example of a radiation detector according to the second embodiment.

[0041] Figure 8 This is a schematic plan view showing a radiation detection element according to Embodiment 3.

[0042] Fig. 9This is a schematic plan view showing a second structural example of the signal output electrode in the third embodiment.

[0043] Fig.10 This is a schematic plan view showing a third structural example of the signal output electrode in the third embodiment.

[0044] Fig.11 This is a block diagram showing the structure of a radiation detection device according to a fourth embodiment.

[0045] Fig.12 It is a schematic diagram showing an example of the internal structure of a radiation detector according to a fourth embodiment.

[0046] Fig.13 This is a schematic perspective view showing an example of arrangement of a plurality of radiation detectors according to the fourth embodiment.

[0047] Fig.14 It is a schematic diagram showing an example of arrangement of an irradiation unit, a radiation detector, and a sample according to a fourth embodiment. DETAILED DESCRIPTION

[0048] Hereinafter, the present invention will be described in detail based on the drawings showing embodiments.

[0049] (Implementation Method 1)

[0050] Figure 1 is a schematic cross-sectional view showing a configuration example of the radiation detector 1 according to the first embodiment. Figure 2 This is a block diagram showing the structure of the radiation detection device 10 of Embodiment 1. The radiation detection device is, for example, a fluorescent X-ray analysis device. The radiation detection device 10 includes an irradiation unit 4 for irradiating a sample 6 with radiation such as electron beams or X-rays, a sample stand 5 for placing the sample 6, and a radiation detector 1. The radiation is irradiated from the irradiation unit 4 to the sample 6, generating radiation such as fluorescent X-rays in the sample 6, and the radiation detector 1 detects the radiation generated from the sample 6. In the figure, the radiation is represented by arrows. The radiation detector 1 outputs a signal proportional to the energy of the detected radiation. In addition, the radiation detection device 10 may also be a method of holding the sample 6 by a method other than the method of placing it on the sample stand 5.

[0051] The radiation detector 1 is connected to a signal processing unit 2 for processing the output signal and a voltage applying unit 34 for applying a voltage required for radiation detection to the radiation detection element 11 provided in the radiation detector 1. The signal processing unit 2 counts the signals of various values ​​output by the radiation detector 1 and generates a relationship between the energy of the radiation and the count, that is, a spectrum of the radiation. The signal processing unit 2 corresponds to the spectrum generating unit.

[0052] The signal processing unit 2 is connected to the analysis unit 32. The analysis unit 32 is configured to include a calculation unit for performing calculations and a memory for storing data. The signal processing unit 2, the analysis unit 32, the voltage application unit 34 and the irradiation unit 4 are connected to the control unit 31. The control unit 31 controls the operations of the signal processing unit 2, the analysis unit 32, the voltage application unit 34 and the irradiation unit 4. The signal processing unit 2 outputs data representing the generated spectrum to the analysis unit 32. The analysis unit 32 inputs the data from the signal processing unit 2, and performs qualitative analysis or quantitative analysis of the elements contained in the sample 6 based on the spectrum shown by the input data. A display unit 33 such as a liquid crystal display is connected to the analysis unit 32. The display unit 33 displays the analysis results of the analysis unit 32. In addition, the display unit 33 displays the spectrum generated by the signal processing unit 2. The control unit 31 may also be a structure that receives the user's operation and controls each part of the radiation detection device 10 according to the received operation. In addition, the control unit 31 and the analysis unit 32 may also be composed of the same computer.

[0053] like Figure 1 As shown, the radiation detector 1 includes a plate-shaped bottom plate 14. A cover 13 in the shape of a lid is covered on one side of the bottom plate 14. The cover 13 is in the shape of a truncated cone connected to one end of a cylinder, and the other end of the cylinder is connected to the bottom plate 14. An opening 131 is formed in the truncated portion of the front end of the cover 13. No window having a window member is provided in the opening 131, and the opening 131 is not blocked. The cover 13 and the bottom plate 14 constitute the housing of the radiation detector 1. The inside of the cover 13 and the bottom plate 14 is not airtight. Here, the airtight state refers to a state in which there is no gas exchange between the inside and outside of the cover 13 and the bottom plate 14. That is, in the present embodiment, there is gas exchange between the inside and outside of the cover 13 and the bottom plate 14. The gas enters and exits between the inside and outside of the cover 13 and the bottom plate 14 through the opening 131 or other parts.

[0054] A radiation detection element 11 and a substrate 12 are arranged inside the cover 13. The substrate 12 has a surface opposite to the opening 131, and the radiation detection element 11 is arranged on the surface. There may be inclusions between the substrate 12 and the radiation detection element 11. Preferably, the substrate 12 is formed of a material that generates as little radiation as possible by irradiation with radiation. The material of the substrate 12 is, for example, ceramic. The radiation detection element 11 is a silicon drift type radiation detection element, and the radiation detector 1 is a silicon drift type radiation detector. For example, the radiation detection element 11 is plate-shaped. The radiation detection element 11 is arranged at a position opposite to the opening 131. In recent years, through the reduction of noise in circuits, etc., the radiation detector can obtain sufficient performance even without cooling. Therefore, the radiation detection element 11 can operate without cooling. That is, the radiation detection element 11 can operate at room temperature. The radiation detector 1 does not have a cooling unit such as a Peltier element for cooling the radiation detection element 11.

[0055] Wiring is provided on the substrate 12. The wiring of the substrate 12 is electrically connected to the radiation detection element 11 via the bonding wire 153. In order to pass the bonding wire 153, a recessed portion recessed from the inner surface of the cover 13 is formed in the cover 13. By having the recessed portion, the radiation detector 1 is prevented from being enlarged as a whole in order to pass the bonding wire 153. As described later, the wiring of the substrate 12 and the radiation detection element 11 can be connected by a method other than the method of connecting the bonding wire 153 to the radiation detection element 11. An amplifier 151 and various components 152 required for the operation of the radiation detector 1 are provided on the surface of the substrate 12 opposite to the surface opposite to the opening 131. For example, the component 152 includes a component for ESD (electro-static discharge) countermeasures. The component for ESD countermeasures is, for example, a capacitor, a diode or a varistor. Compared with the method in which the opening is blocked, the radiation detector 1 is easily affected by the outside. By including components for ESD countermeasures, the radiation detector 1 can strengthen EDS countermeasures and suppress adverse effects caused by EDS.

[0056] The substrate 12 is provided with a through hole. The amplifier 151 is connected to the radiation detection element 11 via a bonding wire 154 arranged to pass through the through hole. The amplifier 151 and the component 152 are electrically connected to the wiring of the substrate 12. Figure 1 The shape of the substrate 12 shown is an example, and the substrate 12 may not have a through hole, and the amplifier 151 may be connected to the radiation detection element 11 by a method other than the method of using the bonding wire 154 passing through the through hole.

[0057] Furthermore, the radiation detector 1 includes a plurality of pins 17. The pins 17 penetrate the bottom plate portion 14. The wiring of the substrate 12 is electrically connected to the pins 17. The pins 17 are used to apply voltage to the radiation detection element 11 and input and output signals.

[0058] The amplifier 151 is, for example, a preamplifier. The radiation detection element 11 outputs a signal proportional to the energy of the detected radiation, and the output signal is input to the amplifier 151 through the bonding wire 154. The amplifier 151 performs signal conversion and amplification. The converted and amplified signal is output from the amplifier 151 and output to the outside of the radiation detector 1 through the pin 17. In this way, the radiation detector 1 outputs a signal proportional to the energy of the radiation detected by the radiation detection element 11. The output signal is input to the signal processing unit 2. In addition, the amplifier 151 can also have functions other than preamplification. In addition, the amplifier 151 can also be configured outside the radiation detector 1.

[0059] The signal processing unit 2 may also have a function of correcting the effect of temperature on the signal from the amplifier 151. The intensity of the signal output from the radiation detection element 11 is affected by temperature. In the radiation detection element 11, a leakage current that does not originate from radiation is generated, and the signal from the amplifier 151 includes a signal corresponding to the leakage current. The leakage current is affected by temperature. The signal processing unit 2 may perform the following processing: based on the signal corresponding to the leakage current, the degree of the effect of temperature on the signal is determined, and the effect of temperature on the signal from the amplifier 151 is corrected according to the determined degree. In addition, the radiation detector 1 may also have a temperature measuring unit such as a thermistor for measuring the temperature inside the radiation detector 1. The signal processing unit 2 may also perform processing to correct the effect of temperature on the signal from the amplifier 151 based on the temperature measurement result of the temperature measuring unit. In addition, the analysis unit 32 may also perform processing to correct the effect of temperature on the signal.

[0060] Figure 3 1 is a schematic cross-sectional view showing a portion of the radiation detection element 11 and the cover 13 of Embodiment 1. The radiation detection element 11 has a surface 111 opposite to the opening 131. The radiation detection element 11 has a light shielding film 161 covering a portion of the surface 111. The surface 111 is larger than the opening 131. When viewed from a viewpoint opposite to the surface 111 of the radiation detection element 11 in a direction orthogonal to the surface 111, a portion of the cover 13 overlaps with a portion of the surface 111. The portion of the cover 13 that overlaps with a portion of the surface 111 is defined as an overlapping portion 132. The overlapping portion 132 includes an edge of the opening 131. The overlapping portion 132 is bonded to the surface 111 of the radiation detection element 11 via an adhesive member 162.

[0061] The radiation detection element 11 has a plate-shaped semiconductor portion 112. The composition of the semiconductor portion 112 is, for example, n-type Si (silicon). A first electrode 113 is provided on the surface 111. The first electrode 113 is continuously provided in an area including the central portion of the surface 111. The first electrode 113 is provided to the vicinity of the periphery of the surface 111 and occupies most of the surface 111. The first electrode 113 is connected to the voltage application portion 34. On the back side of the radiation detection element 11 on the opposite side to the surface 111, multiple ring-shaped second electrodes 114 are provided. In addition, an electrode that outputs a signal during radiation detection, that is, a signal output electrode 115 is provided at a position surrounded by the multiple second electrodes 114. The signal output electrode 115 is connected to the amplifier 151. The second electrode 114 closest to the signal output electrode 115 and the second electrode 114 farthest from the signal output electrode 115 among the multiple second electrodes 114 are connected to the voltage application portion 34.

[0062] The voltage applying unit 34 applies voltage to the multiple second electrodes 114 in such a manner that the potential of the second electrode 114 closest to the signal output electrode 115 is the highest and the potential of the second electrode 114 farthest from the signal output electrode 115 is the lowest. In addition, the radiation detection element 11 is configured to generate a predetermined resistance between adjacent second electrodes 114. For example, by adjusting the chemical composition of a portion of the semiconductor portion 112 located between adjacent second electrodes 114, a resistance channel connected to two second electrodes 114 is formed. That is, the multiple second electrodes 114 are connected in a series via resistors. By applying voltage from the voltage applying unit 34 to such multiple second electrodes 114, each second electrode 114 has a potential that monotonically increases in sequence from the second electrode 114 far away from the signal output electrode 115 toward the second electrode 114 close to the signal output electrode 115. In addition, among the multiple second electrodes 114, a pair of adjacent second electrodes 114 with the same potential may also be included.

[0063] According to the potentials of the plurality of second electrodes 114, an electric field is generated in stages in the semiconductor portion 112, where the potential becomes higher as it approaches the signal output electrode 115 and becomes lower as it moves away from the signal output electrode 115. Furthermore, the voltage applying portion 34 applies a voltage to the first electrode 113 in such a manner that the potential of the first electrode 113 becomes lower than the second electrode 114 having the highest potential. In this way, a voltage is applied to the semiconductor portion 112 between the first electrode 113 and the second electrode 114, and an electric field is generated in the semiconductor portion 112, where the potential becomes higher as it approaches the signal output electrode 115.

[0064] The radiation detector 1 is configured so that the opening 131 faces the loading surface of the sample stage 5. That is, in a state where the sample 6 is loaded on the sample stage 5, the surface 111 of the radiation detection element 11 faces the sample 6. The radiation from the sample 6 passes through the first electrode 113 and enters the semiconductor part 112 from the surface 111. The radiation is absorbed by the semiconductor part 112, and an amount of charge corresponding to the energy of the absorbed radiation is generated. The generated charges are electrons and holes. The generated charges move through the electric field inside the semiconductor part 112, and one type of charge flows into the signal output electrode 115. In the present embodiment, when the signal output electrode 115 is of n-type, the electrons generated by the incidence of radiation move and flow into the signal output electrode 115. The charges flowing into the signal output electrode 115 become a current signal output and are input to the amplifier 151.

[0065] like Figure 3 As shown, the first electrode 113 is not provided in the peripheral portion of the surface 111 of the radiation detection element 11. The portion of the semiconductor portion 112 that can detect incident radiation is a portion where an electric field is generated by applying voltage to the first electrode 113 and the second electrode 114 to cause charges to flow toward the signal output electrode 115. The area of ​​the surface 111 that is the portion of the semiconductor portion 112 that can detect radiation is set as the sensitive area 116. Radiation incident on the sensitive area 116 can be detected by the radiation detection element 11. In the semiconductor portion 112, the area other than the sensitive area 116 is set as the portion of the surface, and the electric field for causing charges to flow toward the signal output electrode 115 is not generated, or the intensity of the electric field for causing charges to flow toward the signal output electrode 115 is weak, making it difficult to detect the incident radiation. For example, the sensitive area 116 is an area including the central portion of the surface 111, and the edge of the surface 111 is not included in the sensitive area 116.

[0066] The overlapping portion 132 of the cover 13 overlaps with an area including the edge of the surface 111. The portion of the surface 111 surrounded by the portion overlapping the overlapping portion 132 does not overlap the overlapping portion 132 and is included in the sensitive area 116. For example, the overlapping portion 132 overlaps with an area other than the sensitive area 116 and a part of the sensitive area 116. In addition, for example, the overlapping portion 132 overlaps with an area that is not the sensitive area 116, and the sensitive area 116 is opposite to the opening 131. The overlapping portion 132 is made of a material that has a light-shielding property and shields radiation. For example, the overlapping portion 132 is made of a metal-containing material. More specifically, the overlapping portion 132 is made of a metal, or is made of a resin mixed with a metal such as barium having an atomic number greater than zinc. The overlapping portion 132 can effectively shield radiation by being made of a metal-containing material. A portion of the radiation incident on the radiation detector 1 is shielded by the overlapping portion 132 , and the radiation that is not shielded by the overlapping portion 132 and passes through the opening 131 is incident on the sensitive area 116 and is detected by the radiation detection element 11 .

[0067] That is, the overlapping portion 132 functions as a collimator that limits the range of radiation incidence. Therefore, in the radiation detector 1, the performance of radiation detection is not reduced compared to the past, and a collimator is not required. That is, the radiation detector 1 does not include a collimator. Since a collimator is not arranged inside the cover 13, the size of the cover 13 is small compared to the conventional radiation detectors with a collimator, and the size of the radiation detector 1 is small.

[0068] The adhesive member 162 has a light-shielding property. By making the adhesive member 162 have a light-shielding property, light is prevented from entering the inside of the incident cover 13 and the light is prevented from entering the radiation detection element 11, thereby preventing noise from being generated due to light. If the light-shielding film 161 is buried between the cover 13 and the radiation detection element 11, the light-shielding film 161 can be used to shield the cover 13 and the radiation detection element 11. However, in the case where the adhesive member 162 is thicker than the light-shielding film 161, the light-shielding film 161 cannot be buried between the cover 13 and the radiation detection element 11, and the adhesive member 162 needs to have a light-shielding property. Since the adhesive member 162 is often thicker than the light-shielding film 161, it is preferred that the adhesive member 162 has a light-shielding property. It is preferred that the adhesive member 162 reduce the amount of light to less than 0.1%. By reducing the amount of light to less than 0.1%, the generation of noise can be effectively prevented. The light can also be reduced to zero.

[0069] In the case where the overlapping portion 132 is made of a metal-containing material or the overlapping portion 132 is conductive, the adhesive member 162 has insulating properties. Since the adhesive member 162 has insulating properties, electrical contact between the overlapping portion 132 and the radiation detection element 11 is prevented, and voltage is prevented from being applied to the cover 13. Thus, the voltage applied to the radiation detection element 11 is prevented from becoming unstable, and the performance of the radiation detector 1 is prevented from being reduced. Preferably, the adhesive member 162 is provided throughout the entire peripheral portion of the surface 111. In the case where the adhesive member 162 is provided throughout the entire peripheral portion of the surface 111, light does not enter the interior of the cover 13. In addition, when the radiation detector 1 is assembled, the radiation detection element 11 can be easily positioned relative to the cover 13. In addition, other structures such as a protective film may be sandwiched between the surface 111 of the radiation detection element 11 and the adhesive member 162.

[0070] The adhesive member 162 may not have insulating properties. In the case where the overlapping portion 132 is not conductive, the adhesive member 162 may not have insulating properties. In addition, in the case where the adhesive member 162 is not insulating and the overlapping portion 132 is conductive, the radiation detector 1 may be a method in which the wiring of the radiation detection element 11 and the substrate 12 are connected via the overlapping portion 132. For example, the radiation detection element 11 is electrically connected to the overlapping portion 132, and the wiring of the overlapping portion 132 and the substrate 12 are connected via a bonding wire. In this way, the radiation detection element 11 is connected to the wiring of the substrate 12 by a method other than the method of connecting the radiation detection element 11 with the bonding wire 153. A voltage is applied to the overlapping portion 132 through the wiring of the substrate 12, and a voltage is applied to the radiation detection element 11 through the overlapping portion 132. In this case, insulation is required between the overlapping portion 132 and the bottom plate portion 14, the pin 17, and the substrate 12.

[0071] The portion of the surface 111 of the radiation detection element 11 surrounded by the portion overlapping the overlapping portion 132 is covered by the light shielding film 161. The position on the surface 111 opposite to the light shielding film 161 is opened by the opening 131. The radiation detector 1 is also used in a state where the light shielding film 161 is in a vacuum or in a state where the light shielding film 161 is exposed to the atmosphere. The light shielding film 161 prevents light from entering the surface 111, and prevents noise from being generated in the radiation detection element 11 due to light. In particular, the light shielding film 161 prevents noise caused by light from being generated in the portion of the radiation detection element 11 where radiation enters. It is preferred that the light shielding film 161 reduces the amount of light to less than 0.1%. By reducing the amount of light incident on the surface 111 to less than 0.1%, the noise generated in the radiation detection element 11 is sufficiently reduced. Since the light shielding film 161 shields the light incident on the radiation detection element 11, the radiation detector 1 can be used in an environment where visible light enters the radiation detector 1.

[0072] Figure 4 1 is a schematic cross-sectional view showing an example of a light-shielding film 161. A light-shielding film 161 composed of a metal film is provided on the surface 111 of the radiation detection element 11. The light-shielding film 161 composed of a metal film has a light-shielding property. The components of the light-shielding film 161 composed of a metal film are, for example, Al (aluminum), Au (gold), a lithium alloy, beryllium or magnesium. In the case where the light-shielding film 161 is composed of Al, it is preferred that the thickness of the light-shielding film 161 is greater than 50nm and less than 500nm. By making the thickness of the light-shielding film 161 composed of Al greater than 50nm, the light-shielding property required to reduce the noise of the radiation detection element 11 can be obtained. When the thickness of the light-shielding film 161 is greater than 500nm, the sensitivity of low-energy X-rays is reduced. More preferably, the thickness of the light-shielding film 161 composed of Al is greater than 100nm and less than 350nm. An oxide film may also exist between the light-shielding film 161 and the first electrode 113. Furthermore, a protective film for protecting the light shielding film 161 may be provided on the surface of the light shielding film 161. For example, the protective film may be made of Al2O3 (aluminum oxide) or SiO2 (silicon dioxide).

[0073] Figure 51 is a schematic cross-sectional view showing another example of a light-shielding film 161. A metal film 163 is provided on the surface 111 of the radiation detection element 11, and a light-shielding film 161 composed of a carbon film is provided on the metal film 163. The component of the metal film 163 is, for example, Al or Au. The component of the light-shielding film 161 composed of a carbon film is, for example, graphene carbon. In the case where the light-shielding film 161 is composed of a carbon film, light shielding can also be effectively performed. The carbon film has excellent chemical resistance and corrosion resistance, and is difficult to pass through visible light but easy to pass through X-rays. In addition, compared with metal films, carbon films are difficult to generate characteristic X-rays through radiation irradiation. Therefore, it is difficult to generate a so-called system peak during radiation detection, and the accuracy of radiation detection becomes higher. A protective film for protecting the light-shielding film 161 may exist on the surface of the light-shielding film 161 overlapping with the metal film 163. For example, the component of the protective film may also be Al2O3 or SiO2. Furthermore, the radiation detector 1 may not include the metal film 163, and the light shielding film 161 composed of a carbon film may be directly provided on the surface 111 of the radiation detection element 11. Furthermore, an oxide film may exist between the surface 111 of the radiation detection element 11 and the metal film 163 or the light shielding film 161 composed of a carbon film.

[0074] The light shielding film 161 may not be a part of the radiation detection element 11 . Figure 6 1 is a schematic cross-sectional view showing another structural example of the radiation detector 1 according to the first embodiment. The portion of the surface 111 of the radiation detection element 11 surrounded by the portion overlapped by the overlapping portion 132, the end surface of the overlapping portion 132, and a portion of the overlapping portion 132 are covered by the light shielding film 161. The structure of the radiation detector 1 other than the light shielding film 161 is the same as that of the embodiment 1. Figure 1 For example, the light shielding film 161 is formed in the last step of assembling the radiation detector 1, thereby forming Figure 6 In this example, the light shielding film 161 is a component of the radiation detector 1 that is different from the radiation detection element 11. In this example, a position on the surface 111 that faces the light shielding film 161 is also open.

[0075] In the present embodiment, the portion of the surface 111 of the radiation detection element 11 surrounded by the overlapping portion of the cover 13 is covered with the light-shielding film 161, so that the radiation detection element 11 can prevent the generation of noise caused by light and can perform radiation detection. Therefore, there is no need to provide a window with a window member in the opening 131 for light shielding. In addition, the radiation detector 1 does not have a cooling unit, and the inner sides of the cover 13 and the bottom plate 14 are not airtight, so there is no need to provide a window with a window member in the opening 131 for airtightness. Therefore, the radiation detector 1 does not have a window with a window member, and the opening 131 is not blocked. Here, "the opening 131 is not blocked" means that the position opposite to the light-shielding film 161 provided on the surface 111 of the radiation detection element 11 is open. For example, in Figure 6 In the example of , the opening 131 is not blocked. Since the radiation detector 1 does not have a window having a window member, the radiation does not pass through the window member, and low-energy radiation is more easily incident on the radiation detection element 11. Therefore, in the radiation detector 1, the detection sensitivity of low-energy radiation is improved. In the radiation detection device 10, the analysis of light elements that radiate low-energy radiation becomes easy.

[0076] In addition, in the present embodiment, since the radiation detector 1 does not include a window having a window member, the size of the radiation detector 1 is smaller than in the past. In addition, since the radiation detector 1 does not include a collimator, the size of the radiation detector 1 is smaller than in the past. In addition, since the cooling unit is not arranged inside the cover 13, the size of the cover 13 is smaller than in the past, and the size of the radiation detector 1 is smaller. In addition, since the inside of the cover 13 and the bottom plate 14 is not airtight, the cover 13 and the bottom plate 14 do not need to have strength and size for maintaining an airtight state. For example, the portion other than the overlapping portion 132 of the cover 13 may also be made of resin. Therefore, the size of the cover 13 and the bottom plate 14 can be reduced, and the size of the radiation detector 1 is small. Since the size of the radiation detector 1 is smaller than in the past, in the radiation detection device 10, the radiation detector 1 can be arranged closer to the sample stage 5 than in the past. That is, the radiation detection element 11 can be closer to the sample 6 than in the past. By bringing the radiation detection element 11 closer to the sample 6, the detection efficiency of the radiation generated from the sample 6 is improved. Therefore, in the radiation detection device 10 , the detection efficiency of the radiation generated from the sample 6 is improved.

[0077] (Implementation Method 2)

[0078] Figure 71 is a schematic cross-sectional view showing a structural example of a radiation detector 1 according to Embodiment 2. A filler 181 is filled in a gap between the radiation detection element 11 and the substrate 12 and the inner wall of the cover 13. In addition, a filler 182 is filled in a gap between the radiation detection element 11 and the substrate 12 and the inner wall of the bottom plate portion 14. The fillers 181 and 182 have insulating properties. It is preferred that the fillers 181 and 182 have light shielding properties. The material of the fillers 181 and 182 is, for example, resin. The fillers 181 and 182 may not completely fill the gap, and a gap not filled with the fillers 181 and 182 may remain. However, it is preferred that the bonding wire 153 is buried in the filler 181, and it is preferred that the bonding wire 154 is buried in the filler 182. The structure of the other parts of the radiation detector 1 is the same as that of Embodiment 1, and the structure of the radiation detection element 11 is the same as that of Embodiment 1. In addition, the structure of the radiation detection device 10 other than the radiation detector 1 is the same as that of Embodiment 1.

[0079] The fillers 181 and 182 preferably have a light shielding property. By making the fillers 181 and 182 have a light shielding property, light can be more effectively prevented from entering the radiation detection element 11, and noise generated in the radiation detection element 11 due to light can be more effectively prevented.

[0080] The bonding leads 153 and 154 are protected from moisture by being buried in the fillers 181 and 182. Therefore, the bonding leads 153 and 154 are prevented from being degraded by moisture. In addition, the bonding leads 153 are prevented from being separated from the radiation detection element 11 or the substrate 12, and the bonding leads 154 are prevented from being separated from the radiation detection element 11 or the amplifier 151.

[0081] The fillers 181 and 182 protect the radiation detection element 11 and the substrate 12 from moisture. Therefore, the electrodes and wirings provided on the radiation detection element 11 and the substrate 12 are prevented from being degraded by moisture. In addition, by covering with the fillers 181 and 182, leakage of current in the electrodes and wirings provided on the radiation detection element 11 and the substrate 12 is suppressed. As described above, by providing the fillers 181 and 182, the durability of the radiation detector 1 is improved.

[0082] (Implementation method 3)

[0083] Figure 8 FIG. 1 is a schematic plan view of the radiation detection element 11 according to Embodiment 3. Figure 8, shows the radiation detection element 11 as viewed from the back surface 117 on the opposite side to the surface 111. A plurality of groups of signal output electrodes 115 and a plurality of second electrodes 114 that surround the signal output electrodes 115 are provided on the back surface 117 of the semiconductor portion 112. The second electrode 114 has a shape in which the length in one direction along the back surface 117 is greater than the length in other directions along the back surface 117. A direction in which the length is greater than the length in other directions is defined as a long direction. For example, the shape of the second electrode 114 is an ellipse when viewed from above, and the long direction is a direction along the long axis of the ellipse. The plurality of groups of second electrodes 114 are arranged in a direction intersecting the long direction. Figure 8 2 shows an example in which two groups of second electrodes 114 are provided. The number of groups of multiple second electrodes 114 may be two or more. Figure 8 2 shows an example in which each group includes three second electrodes 114 , but in reality, more second electrodes 114 are provided.

[0084] At a position surrounded by each group of multiple second electrodes 114, a signal output electrode 115 composed of a plurality of small electrodes 1151 is provided. The plurality of small electrodes 1151 are arranged along the longitudinal direction. The plurality of small electrodes 1151 are connected to each other by a lead 1152. As in the first or second embodiment, the first electrode 113 is provided on the surface 111, and the radiation detector 1 has a light shielding film 161. The first electrode 113, the innermost second electrode 114, and the outermost second electrode 114 are connected to the voltage applying unit 34. By applying a voltage by the voltage applying unit 34, an electric field with a higher potential is generated inside the semiconductor unit 112 as it approaches the signal output electrode 115. Charges flow into each small electrode 1151. The plurality of signal output electrodes 115 are connected to the amplifier 151. In addition, the radiation detector 1 may also include a plurality of amplifiers 151, and the amplifiers 151 are connected to the signal output electrodes 115 one-to-one. Since a plurality of small electrodes 1151 are connected, even if the amplifier 151 is not connected to each small electrode 1151, it only needs to be connected to the signal output electrode 115. Compared with the case where the amplifier 151 is connected to each small electrode 1151, the number of amplifiers 151 is reduced, and the number of components of the radiation detection element 11 is reduced. The structure of the other parts of the radiation detector 1 and the structure of the radiation detection device 10 are the same as those of the first or second embodiment.

[0085] In Embodiment 3, by arranging a plurality of sets of second electrodes 114 and signal output electrodes 115 in a direction intersecting the long direction, the radiation detection element 11 can improve the accuracy of radiation detection in the direction intersecting the long direction. When the signal output electrode 115 is a single electrode and the size of the signal output electrode 115 is substantially equal in any direction along the back surface 117, the distance between the signal output electrode 115 and the second electrode 114 changes according to the direction along the back surface 117. The electric field generated in the semiconductor portion 112 is different depending on the direction, and the speed of the charge flow is the same depending on the position where the charge is generated in the semiconductor portion 112. Therefore, the speed at which the charge moves to the signal output electrode 115 is biased, the time required for signal processing increases, and the time resolution of radiation detection decreases. When the signal output electrode 115 has a shape that is long in the long direction, although the distance between the signal output electrode 115 and the second electrode 114 is equal, the area of ​​the signal output electrode 115 becomes larger. As the area becomes larger, the capacitance of the signal output electrode 115 becomes larger, the signal per charge becomes smaller, and the noise ratio of the signal intensity during radiation detection deteriorates.

[0086] In Embodiment 3, instead of the signal output electrode 115 having a shape that is long in the longitudinal direction, the signal output electrode 115 is constituted by including a plurality of small electrodes 1151, thereby suppressing the increase in the area of ​​the signal output electrode 115. The increase in the capacitance of the signal output electrode 115 is suppressed, and the deterioration of the noise ratio of the signal intensity during radiation detection is suppressed. In addition, by arranging a plurality of small electrodes 1151 along the longitudinal direction, the change in the distance between the signal output electrode 115 and the second electrode 114 is small. Therefore, the deviation in the speed at which the charge moves to the signal output electrode 115 is small, and the increase in the time required for signal processing is suppressed, thereby suppressing the reduction in the temporal resolution of radiation detection. In addition, the radiation detection element 11 may also include a second electrode 114 that surrounds the small electrode 1151 individually. For example, the second electrode 114 may surround each small electrode 1151 individually, and the plurality of small electrodes 1151 may be connected by a lead 1152, and other second electrodes 114 may surround the small electrode 1151 and a plurality of groups of the second electrodes 114 that surround the small electrode 1151.

[0087] Fig. 91 is a schematic top view showing a second structural example of the signal output electrode 115 in Embodiment 3. The signal output electrode 115 is composed of a plurality of small electrodes 1151. The plurality of small electrodes 1151 are arranged along the longitudinal direction. The plurality of small electrodes 1151 are connected to each other via a wire electrode 1153 provided on the back surface 117. The wire electrode 1153 is a linear electrode and is composed of the same components as the small electrode 1151. Charges also flow into the wire electrode 1153. In this structure, the increase in the area of ​​the signal output electrode 115 can also be suppressed. In addition, the deviation in the distance between the signal output electrode 115 and the second electrode 114 is small, and the deviation in the speed at which the charges move to the signal output electrode 115 is small.

[0088] Fig.10 1 is a schematic top view showing a third structural example of the signal output electrode 115 in Embodiment 3. The signal output electrode 115 includes a single small electrode 1151 and a linear electrode 1153 provided on the back surface 117. The linear electrode 1153 is connected to the small electrode 1151 and extends along the longitudinal direction. In this structure, it is also possible to suppress the increase in the area of ​​the signal output electrode 115. In addition, by extending the linear electrode 1153 along the longitudinal direction, the portion of the second electrode 114 away from the small electrode 1151 is closer to the linear electrode 1153. Therefore, in addition, the deviation of the distance between the signal output electrode 115 and the second electrode 114 is small, and the deviation of the speed of charge moving to the signal output electrode 115 is small.

[0089] In Embodiment 3, the radiation detection element 11 is provided with a plurality of signal output electrodes 115 and multiple second electrodes 114, but the radiation detection element 11 may be provided with only one signal output electrode 115 and multiple second electrodes 114 having a length in one direction greater than the length in other directions. In addition, the radiation detector 1 of Embodiment 3 may be provided with a window member blocking the opening 131. The radiation detector 1 in which the opening 131 is blocked by the window member may not have the light shielding film 161 or the light shielding adhesive member 162.

[0090] (Implementation 4)

[0091] Fig.11This is a block diagram showing the structure of the radiation detection device 10 of the fourth embodiment. The radiation detection device 10 of the fourth embodiment includes a plurality of radiation detectors 1. The irradiation unit 4 irradiates radiation to the sample 6, and the radiation generated from the sample 6 is detected by the plurality of radiation detectors 1. Radiation is represented by arrows in the figure. The plurality of radiation detectors 1 are respectively connected to the voltage application unit 34 and the signal processing unit 2. The voltage application unit 34 applies a voltage to the radiation detection element 11 in each radiation detector 1. The signal processing unit 2 processes the signals output from the plurality of radiation detectors 1. The analysis unit 32 performs various analyses based on the detection results of the plurality of radiation detectors 1. In addition, the radiation detection device 10 may also include a plurality of voltage application units 34 and a signal processing unit 2, and one radiation detector 1 is connected to one voltage application unit 34 and the signal processing unit 2.

[0092] Fig.12 Schematic diagram showing an example of the internal structure of the radiation detector 1 according to the fourth embodiment. Fig.12 1 shows the arrangement of the radiation detection elements 11 in the radiation detector 1 from above. The radiation detector 1 includes a plurality of radiation detection elements 11. The plurality of radiation detection elements 11 are arranged inside the cover 13 with their surfaces 111 facing the same direction. Fig.12 As shown in FIG. 1 , a plurality of radiation detection elements 11 are arranged in two rows. Fig.12 , an example in which seven radiation detection elements 11 are arranged in the radiation detector 1 is shown, but the number of radiation detection elements 11 in the radiation detector 1 may be a number other than seven. The plurality of radiation detection elements 11 may be formed integrally or may be separated individually. The structure of each radiation detection element 11 is the same as that of any one of Embodiments 1 to 3. The radiation detector 1 includes a plurality of amplifiers 151, and the signal output electrodes 115 in the radiation detection elements 11 are respectively connected to the amplifiers 151. In addition, the radiation detector 1 may include amplifiers 151 less than the number of radiation detection elements 11, and a plurality of signal output electrodes 115 are connected to one amplifier 151. The structure of the other parts of the radiation detector 1 is the same as that of Embodiments 1 to 3. In addition, the structure of the other parts of the radiation detection device 10 is the same as that of Embodiments 1 to 3.

[0093] Fig.13This is a schematic stereoscopic diagram showing an example of the configuration of multiple radiation detectors 1 according to Embodiment 4. The solid arrow indicates the radiation such as X-rays irradiated from the irradiation unit 4 to the sample 6. The irradiation position 61 in the figure is the irradiation position of the sample 6 by the irradiation from the irradiation unit 4. The straight line 62 passing through the irradiation position 61 and intersecting the sample 6 is indicated by a single-dash line. For example, the straight line 62 is orthogonal to the surface of the sample 6. Multiple radiation detectors 1 are arranged at positions surrounding the straight line 62. The multiple radiation detectors 1 are arranged so that the front faces are opposite to the irradiation position 61. Therefore, the surface 111 of each radiation detection element 11 is opposite to the irradiation position 61. By irradiating the sample 6 with radiation, radiation such as fluorescent X-rays is generated from the sample 6. The radiation is radially generated from the irradiation position 61 and is incident on each radiation detector 1. In each radiation detector 1, the radiation is incident on each radiation detection element 11, and the radiation is detected. In Fig.13 Although three radiation detectors 1 are shown in FIG. 1 , the number of radiation detectors 1 to be arranged may be two or four or more.

[0094] By arranging a plurality of radiation detectors 1 around the straight line 62, and arranging a plurality of radiation detection elements 11 in the radiation detector 1, radiation is detected by the plurality of radiation detection elements 11. X-rays generated from the sample 6 are incident on any radiation detection element 11 with a high probability and are detected. Therefore, the radiation detection device 10 of the fourth embodiment has a high efficiency in detecting radiation generated from the sample 6. Since the radiation detection efficiency is high, the radiation detection device 10 can shorten the time required to detect radiation generated from the sample 6.

[0095] Fig.14 Schematic diagram showing an example of arrangement of the irradiation unit 4, the radiation detector 1, and the sample 6 of the fourth embodiment. The sample 6 is a long thin sheet, and is moved in the direction indicated by the blank arrow by the roller 63. The irradiation unit 4 and the plurality of radiation detectors 1 are arranged on the lower side of the sample 6. Fig.14 Although two radiation detectors 1 are shown in FIG. 1 , the number of arranged radiation detectors 1 may be three or more. In addition, the irradiation unit 4 and the radiation detector 1 may be arranged separately on the front side and the back side of the sample 6 .

[0096] The sample 6 moves continuously, and the irradiation unit 4 irradiates the sample 6 with radiation continuously. As the sample 6 moves, the radiation is sequentially irradiated to multiple portions on the sample 6, and radiation is sequentially generated from each portion. Multiple radiation detectors 1 sequentially detect the radiation generated from the sample 6, and the analysis unit 32 sequentially analyzes it. Fig.14The dotted arrows in the figure indicate radiation. For example, the radiation detector 1 detects fluorescent X-rays generated from the sample 6, and the analysis unit 32 measures the amount of impurities contained in the sample 6. For example, the analysis unit 32 measures the thickness of the sample 6 from the intensity of the detected fluorescent X-rays, using the fact that the intensity of the fluorescent X-rays of the base material of the sample 6 changes depending on the thickness of the sample 6.

[0097] For example, if the sample 6 is an industrial product, the amount of impurities or the thickness of the sample 6 can be measured using the radiation detection device 10, and if the amount of impurities or the thickness of the sample 6 exceeds the allowable range, the sample 6 is judged to be abnormal. The time required for the radiation detection device 10 to detect the radiation generated from the sample 6 is short, so the time required to judge the abnormality of the sample 6 is also short. Therefore, the moving time of the sample 6 when judging the abnormality of the sample 6 can be accelerated. Therefore, by using the radiation detection device 10 of the fourth embodiment, the production and inspection of the sample 6 can be performed efficiently in terms of time.

[0098] In addition, the radiation detector 1 of Embodiment 4 may also adopt a mode in which the opening 131 is blocked by a window member. The radiation detector 1 in which the opening 131 is blocked by a window member may not include the light shielding film 161 or the light shielding adhesive member 162 .

[0099] In addition, in the above embodiments 1 to 4, the radiation detector 1 is shown as a method without a cooling unit such as a Peltier element, but the radiation detector 1 may also be provided with a temperature adjustment unit for maintaining the temperature of the radiation detection element 11 at a constant level. Although the temperature adjustment unit uses a Peltier element, the cooling capacity may be lower than that of a conventional cooling unit, and the temperature difference between the inner side and the outer side of the cover 13 and the bottom plate 14 is within 10°C, and the temperature will not be cooled to a temperature at which condensation occurs. Since the temperature adjustment unit can reduce the cooling capacity, it is smaller than the conventional cooling unit. Therefore, even in the method with the temperature adjustment unit, the size of the radiation detector 1 is smaller than that of the conventional one. In addition, in embodiments 1 to 4, the radiation detection element 11 is shown as a silicon drift type radiation detection element, but as long as the radiation detection element 11 is a semiconductor element, it may be an element other than the silicon drift type radiation detection element. Therefore, the radiation detector 1 may also be a radiation detector other than the silicon drift type radiation detector. For example, the radiation detector 1 may also be a pixel array type semiconductor detector for detecting X-ray energy.

[0100] In addition, in Embodiments 1 to 4, a method of irradiating the sample 6 with radiation and detecting the radiation generated from the sample 6 is shown, but the radiation detection device 10 may also be a method of detecting the radiation that passes through the sample 6 or is reflected by the sample 6. In addition, the radiation detection device 10 may also be a method of scanning the sample 6 with radiation by changing the direction of the radiation. In addition, the radiation detection device 10 may also be a method that does not include the irradiation unit 4, the sample stage 5, the analysis unit 32, or the display unit 33. Even if the radiation detection device 10 does not include the irradiation unit 4 and the sample stage 5, the radiation detection device 10 can be used in a method in which the radiation detection element 11 is closer to the sample than before, and the detection efficiency of the radiation can be improved.

[0101] The present invention is not limited to the contents of the above-mentioned embodiments, and various modifications can be made within the scope of the claims. That is, embodiments obtained by combining technical means appropriately modified within the scope of the claims are also included in the scope of the present invention.

[0102] Description of reference numerals:

[0103] 1: radiation detector (silicon drift type radiation detector); 10: radiation detection device; 11: radiation detection element (silicon drift type radiation detection element); 111: surface; 13: cover (housing); 131: opening; 132: overlapping part; 14: bottom plate (housing); 161: light shielding film; 162: adhesive member; 2: signal processing unit; 31: control unit; 32: analysis unit; 33: display unit; 4: irradiation unit; 5: sample stand; 6: sample.

Claims

1. A silicon drift type radiation detector, characterized in that: The silicon drift type radiation detector comprises: a housing; and A silicon drift type radiation detection element is arranged inside the housing. The housing has an unobstructed opening, The silicon drift type radiation detection element has a surface facing the opening and on which radiation is incident. A first light-shielding film is directly disposed on the surface, or a metal film is disposed on the surface, and a second light-shielding film is disposed on the metal film.

2. The silicon drift type radiation detector according to claim 1, characterized in that: The first light-shielding film and the second light-shielding film reduce the amount of light incident on the surface to less than 0.1%.

3. The silicon drift type radiation detector according to claim 1, characterized in that: The first light shielding film is a metal film having a thickness exceeding 50 nm and less than 500 nm.

4. The silicon drift type radiation detector according to claim 1, characterized in that: The first light-shielding film and the second light-shielding film are carbon films.

5. The silicon drift type radiation detector according to claim 1, characterized in that: The silicon drift type radiation detection element comprises: a signal output electrode provided on the back surface opposite to the surface, into which charges generated by the incidence of radiation flow and outputs a signal corresponding to the charges; A first electrode, disposed on the surface, to which a voltage is applied; and A plurality of second electrodes are arranged on the back surface, surround the signal output electrode, and have different distances from the signal output electrode. The second electrode has a shape in which a length along one direction of the back surface is greater than a length along other directions of the back surface, The signal output electrode is composed of a plurality of electrodes arranged along the one direction and connected to each other.

6. The silicon drift type radiation detector according to claim 1, characterized in that: The silicon drift type radiation detection element comprises: a signal output electrode provided on the back surface opposite to the surface, into which charges generated by the incidence of radiation flow and outputs a signal corresponding to the charges; A first electrode, disposed on the surface, to which a voltage is applied; and A plurality of second electrodes are arranged on the back surface, surround the signal output electrode, and have different distances from the signal output electrode. The second electrode has a shape in which a length along one direction of the back surface is greater than a length along other directions of the back surface, The signal output electrode includes a conductive line disposed on the back surface and extending along the one direction.

7. The silicon drift type radiation detector according to any one of claims 1 to 6, characterized in that: The surface is larger than the opening, The housing has an overlapping portion including an edge of the opening and overlapping a portion of the surface, A portion of the surface surrounded by the portion overlapped by the overlapping portion is covered by the first light-shielding film or the second light-shielding film.

8. The silicon drift type radiation detector according to any one of claims 1 to 6, characterized in that: does not include a cooling unit for cooling the silicon drift type radiation detection element, The housing is not airtight.

9. The silicon drift type radiation detector according to any one of claims 1 to 6, characterized in that: No window member is provided at a position opposing the surface.

10. The silicon drift type radiation detector according to any one of claims 1 to 6, characterized in that: A filler that fills a gap between the housing and the silicon drift type radiation detection element is also included.

11. A radiation detection device, characterized in that: include: The silicon drift type radiation detector according to any one of claims 1 to 10; as well as The spectrum generating unit generates a spectrum of radiation detected by the silicon drift type radiation detector.

12. A radiation detection device, characterized in that: include: An irradiation unit irradiates radiation to the sample; The silicon drift type radiation detector according to any one of claims 1 to 10, which detects radiation generated from the sample; a spectrum generating unit that generates a spectrum of radiation detected by the silicon drift type radiation detector; as well as The display unit displays the spectrum generated by the spectrum generating unit.

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