JP2012037348A - Radiation detector module - Google Patents

Abstract

A radiation detector module for reducing the influence of noise on a semiconductor element is provided.
A radiation detector module 5 according to the present invention includes a radiation detector card 1 having a semiconductor element 10 that outputs an analog signal in response to incidence of radiation 100, and a portion including both ends of the radiation detector card 1. A radiation detector stand 3 having a pair of supports 2 that support the radiation detector card 1 and a motherboard 2e that includes an analog ground for analog signals on the support side and to which the pair of supports 2 are fixed. And a sheet metal part 6 fixed to one support body 2 and the other support body 2 and electrically connected to an analog ground.
[Selection] Figure 1A

Description

  The present invention relates to a radiation detector module. In particular, the present invention relates to a radiation detector module that detects radiation such as gamma rays and X-rays.

  2. Description of the Related Art Conventionally, a first electrode formed in a rod shape, a semiconductor element that surrounds the first electrode, contacts the first electrode, and receives radiation, and a plurality of second electrodes provided on the outer surface of the semiconductor element There is known a radiation detector including a radiation detection element and an integrated circuit that processes a signal output from the radiation detection element (see, for example, Patent Document 1).

JP 2004-151089 A

  However, in the radiation detector according to Patent Document 1, since the components including the radiation detection element and the integrated circuit are covered by the light shielding shield case, noise from the integrated circuit may enter the radiation detection element.

  Accordingly, an object of the present invention is to provide a radiation detector module that reduces the influence of noise on a semiconductor element.

  In order to achieve the above object, the present invention provides a radiation detector card having a semiconductor element that outputs an analog signal in response to the incidence of radiation, and a pair that supports the radiation detector card at a portion including both ends of the radiation detector card. And a radiation detector stand having an analog ground for analog signals on the support side and a mother board to which the pair of supports are fixed, one support of the pair of supports and the other support And a sheet metal part electrically connected to an analog ground is provided.

  In the radiation detector module, the motherboard has an electronic component for converting an analog signal into a digital signal and a digital ground for the digital signal on the side opposite to the side supporting the radiation detector card, and a sheet metal part Can enclose a region including the boundary between the analog ground and the digital ground, and a region including a part of the radiation detector card.

  In the radiation detector module, the surfaces of the mother boat that contact the pair of supports can be electrically connected to the pair of supports.

  In the radiation detector module, the radiation detector card includes a substrate on which the semiconductor element is mounted, and a support member that supports the substrate at a position away from the end of the semiconductor element, and one support body is The plurality of radiation detector cards are arranged at a predetermined interval corresponding to the interval at which the plurality of radiation detector cards are arranged, and have a plurality of first grooves into which the plurality of radiation detector cards are inserted. In addition to being arranged at a predetermined interval, it may have a plurality of second grooves into which a plurality of radiation detector cards are inserted, and may be arranged in parallel to one of the supports.

  The radiation detector module further includes a gasket having a conductive surface and compressed by an external force on a side surface, the gasket having a side surface corresponding to a boundary between the analog ground and the digital ground. It may be attached to the containing area.

  In the radiation detector module, the sheet metal part may be wound around the radiation detector stand and fixed to the radiation detector stand.

  The radiation detector module according to the present invention can provide a radiation detector module that reduces the influence of noise on the semiconductor element.

It is a perspective view of the radiation detector module which concerns on the 1st Embodiment of this invention. It is a perspective view of a radiation detector card. It is a perspective view of a radiation detector stand. In the top view of a radiation detector stand, it is a schematic diagram showing the state of contact between a mother board and a support. It is a conceptual diagram of the area | region which handles the analog signal in the radiation detector module which concerns on the 1st Embodiment of this invention, and the area | region which handles a digital signal. It is a perspective view of a radiation detector stand and a sheet metal part with which a radiation detector module concerning a 2nd embodiment of the present invention is provided. It is a conceptual diagram which shows the area | region which handles the analog signal in the radiation detector module which concerns on 2nd Embodiment, and the area | region which handles a digital signal. It is a side view at the time of arranging a plurality of radiation detector modules concerning a 2nd embodiment of the present invention.

[First Embodiment]
(Outline of configuration of radiation detector module 5)
FIG. 1A shows an example of a perspective view of the radiation detector module according to the first embodiment of the present invention.

  The radiation detector module 5 according to the first embodiment has a card shape, and includes a plurality of radiation detector cards 1 that detect radiation 100 such as γ rays and X-rays, and a plurality of radiation detector cards 1. And a sheet metal part 6 surrounding a part of the periphery of the radiation detector stand 3. Specifically, the radiation detector module 5 includes a radiation detector card 1 having a semiconductor element 10 that outputs an analog signal in response to the incidence of radiation 100 and a portion including both ends of the radiation detector card 1. A radiation detector stand 3 having a pair of supports 2 that support 1 and a motherboard 2e that includes an analog ground for analog signals on the support 2 side and to which the pair of supports 2 is fixed; And a sheet metal part 6 surrounding the upright 3.

(Configuration of radiation detector card 1)
FIG. 1B shows an example of a perspective view of a radiation detector card.

  The radiation 100 enters from the upper side to the lower side of the page. That is, the radiation 100 propagates along the direction from the semiconductor element 10 of the radiation detector card 1 toward the card holder 30 and the card holder 31 and enters the radiation detector card 1. In the radiation detector card 1, the radiation 100 is incident on the side surface of the semiconductor element 10 (that is, the surface facing upward in FIG. 1B). Therefore, the side surface of the semiconductor element 10 is an incident surface for the radiation 100. As described above, the radiation detector card having the side surface of the semiconductor element 10 as the incident surface of the radiation 100 is referred to as an edge-on type radiation detector card in the present embodiment.

  Specifically, the radiation detector card 1 includes a pair of semiconductor elements 10 capable of detecting radiation 100, a plurality of semiconductor elements 10 and chip components such as resistors and capacitors to which analog signals from the plurality of semiconductor elements 10 are supplied. And a card holder 30 and a card holder 31 as a pair of support members that support the substrate 20 by sandwiching the substrate 20 at positions away from the ends of the pair of semiconductor elements 10. . As an example, four pairs of semiconductor elements 10 are fixed to the substrate 20 at positions where the substrate 20 is sandwiched. That is, the pair of semiconductor elements 10 in each set is fixed to a symmetric position with the substrate 20 as a symmetry plane on each of one surface and the other surface of the substrate 20.

  The substrate 20 is sandwiched and supported by the card holder 30 and the card holder 31. Specifically, the card holder 30 and the card holder 31 are formed to have the same shape, and the protruding portion 36 of the card holder 31 is fitted into the grooved hole 34 of the card holder 30, and the card holder 31. The substrate 20 is supported by fitting a projection (not shown) of the card holder 30 into a grooved hole (not shown) of the card holder 30.

  Moreover, the board | substrate 20 has the card edge part inserted in the connector 4 which the radiation detector stand 3 mentioned later has on the opposite side of the side by which the semiconductor element 10 is mounted (in FIG. 1B, the card edge part is It is covered with the card holder 30 and the card holder 31 and is not shown.) The card edge portion includes a plurality of edge patterns that are electrically connected to the connector 4. The elastic member 32 such as a leaf spring allows the radiation detector card 1 to be attached to the radiation detector stand 3 when the radiation detector card 1 is inserted into the radiation detector stand 3 that supports the plurality of radiation detector cards 1. Press to fix. In this case, the card edge portion is inserted into the connector 4, and the edge pattern formed on the surface of the card edge portion is electrically connected to the connector 4, whereby the radiation detector card 1 is connected to an external electric circuit. Are electrically connected to a control circuit, an external power supply line, a ground line, and the like.

  The radiation detector card 1 electrically connects the electrodes of the semiconductor elements 10 and the plurality of substrate terminals 22 provided on the substrate 20 to the opposite sides of the substrates 20 of the pair of semiconductor elements 10. It further includes a flexible substrate 40 having a wiring pattern (electrodes on the element surface opposite to the substrate 20 of the semiconductor element 10 and wiring patterns on the semiconductor element 10 side of the flexible substrate 40 are not shown).

  The flexible substrate 40 is provided on both the one semiconductor element 10 side and the other semiconductor element 10 side of the pair of semiconductor elements 10 (in the present embodiment, one semiconductor of the four pairs of semiconductor elements 10). A flexible substrate 40 is provided on each of the element 10 side and each of the other semiconductor element 10 side). Then, one end of each of the plurality of wiring patterns of the flexible substrate 40 is electrically connected to an electrode provided on the surface of the semiconductor element 10 opposite to the substrate 20, and the other end of the plurality of wiring patterns of the flexible substrate 40 is connected. Each end is electrically connected to the substrate terminal 22.

(Details of semiconductor element 10)
The semiconductor element 10 is formed in a substantially rectangular parallelepiped shape (that is, formed in a substantially square shape in front view). Moreover, the semiconductor element 10 has an electrode on each of the surface on the substrate 20 side and the surface opposite to the surface. The radiation 100 enters from the end of each semiconductor element 10 and travels through the semiconductor element 10 toward the card edge portion side. In this case, an analog signal corresponding to the incidence of the radiation 100 is supplied from the semiconductor element 10 to chip components such as resistors and capacitors mounted on the substrate 20. And a chip component supplies an analog signal to the electronic component 250 provided in the surface on the opposite side to the side which is supporting the radiation detector card | curd 1 of the motherboard 2e.

In addition, as a material which comprises the semiconductor element 10, CdTe can be used, for example. Further, the semiconductor element 10 is not limited to a CdTe element as long as radiation such as γ rays can be detected. For example, a compound semiconductor element such as a CdZnTe (CZT) element or an HgI ₂ element can also be used as the semiconductor element 10.

(Details of substrate 20)
The substrate 20 is a thin substrate (for example, a glass epoxy substrate such as FR4) on which a conductive thin film (for example, copper foil) made of a conductive material such as a metal conductor is formed, and is made of an insulating material such as a solder resist. It is formed sandwiched between insulating layers. Further, the substrate 20 has an element connection portion that is electrically connected to the electrode of the semiconductor element 10. The electrode of the semiconductor element 10 is electrically connected to the element connection portion via a conductive adhesive such as silver paste.

  Further, the element connection portion is electrically connected to the chip component on the substrate 20 and / or the edge pattern of the card edge portion by wiring formed on the substrate 20. Thereby, in the board | substrate 20, the electrode of the surface at the side of the board | substrate 20 of the semiconductor element 10 is electrically connected by the wiring of the board | substrate 20 with the pattern of a chip component and / or a card edge part. Further, the electrode on the surface opposite to the substrate 20 side of the semiconductor element 10 is electrically connected to the card edge pattern via the wiring pattern of the flexible substrate 40, the substrate terminal 22, and the wiring of the substrate 20. Is done. Here, for example, an electrode on the substrate 20 side of the semiconductor element 10 is an anode electrode, and an electrode on the opposite side of the substrate 20 side of the semiconductor element 10 is a cathode electrode. In this case, the signal from the anode electrode and the signal from the cathode electrode are each led to the pattern of the card edge portion and output to an external electric circuit via the pattern.

(Details of card holder 30 and card holder 31)
Since the card holder 30 and the card holder 31 have substantially the same shape, the card holder 30 will be mainly described below.

  The card holder 30 includes an elastic member 32 such as a leaf spring provided at both ends in the longitudinal direction of the card holder 30, a grooved hole 34 into which the protruding portion 36 of the card holder 31 to be a pair of the card holder 30 is fitted, and the substrate 20. And a plurality of terminal holes 38 through which board terminals 22 are provided. The card holder 30 contacts the substrate 20 from one surface side of the substrate 20, and the card holder 31 contacts the substrate 20 from the other surface side of the substrate 20, thereby sandwiching the substrate 20 between the card holder 30 and the card holder 31. . As a result, the substrate 20 is supported by the card holder 30 and the card holder 31.

(Configuration of radiation detector stand 3)
FIG. 1C shows an example of a perspective view of a radiation detector stand. FIG. 1D shows an outline of the contact state between the mother board and the support in the top view of the radiation detector stand. In FIG. 1C, illustration of the connector is omitted for convenience of explanation. Further, in FIG. 1D, for convenience of explanation, the connector is not shown, and one support body 2 is not shown.

  The radiation detector stand 3 includes a mother board 2e, a pair of supports 2 arranged on the mother board 2e, and having a plurality of grooves 2b into which the radiation detector card 1 is inserted, and a plurality of supports 2 between the pair of supports 2. And a plurality of connectors 4 into which each of the radiation detector cards 1 is inserted. The pair of supports 2 are arranged in parallel with each other at an interval corresponding to the width of the radiation detector card 1. Further, the plurality of grooves 2b are arranged at a predetermined interval corresponding to the interval at which the radiation detector cards 1 are arranged, and are formed along the normal direction of the surface of the mother board 2e. Further, the mother board 2e has an electronic component 250 including a function of converting an analog signal from a chip component on the substrate 20 into a digital signal on a surface opposite to the side supporting the radiation detector card 1, and a digital signal. And a digital ground. As the electronic component 250, ASIC (Application Specific Integrated Circuit), FPGA (Field Programmable Gate Array), or the like can be used.

  The radiation detector card 1 is mounted on a pair of supports 2 along a direction perpendicular to the surface of the mother board 2e. The radiation detector card 1 is then fixed by inserting both ends thereof into the groove 2 b of the support 2. That is, in the radiation detector card 1, one end is inserted into the groove 2 b as the first groove of the one support 2, and the other end is arranged in parallel to the one support 2. It is inserted into the groove 2 b as the second groove of the other support 2 and fixed to the radiation detector stand 3.

  Here, both ends of the radiation detector card 1 are inserted into the grooves 2b along the wall portions 2a, and the card holder 30 and the card holder 31 are fixed to the support 2 of the radiation detector stand 3 by the grooves 2b. At the same time, the card edge portion is inserted into the connector 4. In this case, the elastic member 32 of the radiation detector card 1 fixes the radiation detector card 1 to the support 2 by fitting into the recess 2c of the groove 2b. In addition, the elastic member 32 presses the radiation detector card 1 toward the flat surface 2d side in a state of being fitted in the indented portion 2c.

(Details of sheet metal part 6)
The sheet metal part 6 has a plurality of connection parts 6 a that are electrically connected to each of the pair of supports 2. The connection part 6a is provided in the partial area | region of the both ends of the sheet metal part 6, for example in front view and side view. Here, in the connection part 6a of the sheet metal part 6 provided over one support body 2 and the other support body 2, the distance between the one support body 2 and the other support body 2 is kept constant. For this purpose, it is firmly fixed to each of the pair of supports 2. That is, the connection part 6a of the sheet metal part 6 provided over the pair of supports 2 is compared with the connection part 6a of the sheet metal part 6 provided so as to cover the side surface of one support 2 or the other support 2. The substrate 2 is firmly fixed.

  Specifically, the sheet metal part 6 is fixed to at least one support body 2 and the other support body 2 of the pair of support bodies 2 and is electrically connected to the analog ground of each support body 2. Therefore, the potential of the analog ground and the potential of the sheet metal part 6 are the same. Further, when the sheet metal part 6 is wound around the radiation detector stand 3, for example, the periphery of the radiation detector stand 3 is covered with one sheet metal, and one end and the other end of the sheet metal are caulked. be able to. Thereby, the sheet metal part 6 is fixed to the radiation detector stand 3. Further, in order to keep the distance between one support 2 and the other support 2 constant, the sheet metal part 6 is formed using a metal material having a high mechanical strength, for example, a material harder than aluminum. be able to. As an example, the sheet metal part 6 can be formed using a metal material such as SUS, phosphor bronze, or constantin.

  FIG. 1E conceptually shows an area for handling analog signals and an area for handling digital signals in the radiation detector module according to the first embodiment of the present invention.

  First, referring to FIG. 1D, the pair of supports 2 are fixed to the mother board 2e by screws 7. Specifically, each of the pair of supports 2 is fixed to the mother board 2e by a screw 7 passing through a screw hole 2g of the mother board 2e near one side of the mother board 2e and near the other side of the one side. In this case, the insulating layer is peeled off from the surface of the mother board 2e that contacts the pair of supports 2. The surface from which the insulating layer is peeled becomes a contact region 2 f that contacts the support 2. Thereby, the mother board 2e and the pair of supports 2 are electrically connected in the contact region 2f.

  Therefore, the analog ground of the radiation detector card 1 has a path that passes through the card edge portion, the connector 4 of the motherboard 2e, the motherboard 2e, and the pair of supports 2. That is, as shown in FIG. 1E, the area where the radiation detector card 1 of the motherboard 2e is provided (that is, the area above the line 200 in FIG. 1E) is the area where analog signals are handled, and the radiation of the motherboard 2e. The area opposite to the area where the detector card 1 is provided (that is, the area under the line 200 in FIG. 1E) is an area where digital signals are handled. That is, the motherboard 2e separates the area where analog signals are handled from the area where digital signals are handled.

  The mother board 2e is provided with a ground layer electrically connected to the analog ground in the inner layer, specifically, near the position of the line 200 in FIG. 1E. The upper surface and the lower surface of the mother board 2e sandwiching the ground layer are electrically connected through a through hole. Due to the presence of the ground layer, noise can be suppressed from entering the area handling digital signals from the area handling digital signals.

  In the present embodiment, the analog ground and the digital ground are divided on one surface and the other surface of the motherboard 2e. The sheet metal portion 6 is provided at a position surrounding a region including the boundary between the analog ground and the digital ground (that is, a line 200 in FIG. 2) and a region including a part of the radiation detector card 1. That is, the sheet metal part 6 surrounds an area where analog signals are handled. The part of the radiation detector card 1 is a portion of the radiation detector card 1 excluding a portion where the semiconductor element 10 is provided.

(Effects of the first embodiment)
The radiation detector module 5 according to the first embodiment of the present invention handles analog signals on the side of the motherboard 2e where the radiation detector card 1 is provided, and is opposite to the side of the motherboard 2e where the radiation detector card 1 is provided. Since the digital signal is handled on the side, the digital signal hardly enters the analog signal on the radiation detector card 1 side as noise. Thereby, in the radiation detector module 5 which concerns on this Embodiment, degradation of the characteristic of radiation detection by the noise of a digital signal can be suppressed.

  Further, since the radiation detector module 5 according to the first exemplary embodiment surrounds the periphery of the radiation detector stand 3 with the sheet metal part 6, noise from the periphery of the radiation detector module 5 and the electronics of the motherboard 2e. It is possible to prevent noise from the digital signal of the component 250 from entering the radiation detector card 1 side. Furthermore, since the sheet metal part 6 fixes one support body 2 and the other support body 2, it can also suppress that the space between one support body 2 and the other support body 2 expands.

[Second Embodiment]
FIG. 2 is a perspective view of a radiation detector stand and a sheet metal part included in the radiation detector module according to the second embodiment of the present invention. FIG. 3 conceptually shows an area for handling analog signals and an area for handling digital signals in the radiation detector module according to the second embodiment. 2, illustration of the radiation detector card 1 and the connector 4 is omitted for convenience of explanation.

  The radiation detector stand 3a of the radiation detector module 5a according to the second embodiment is different from the radiation detector stand 3 according to the first embodiment except that it further includes a gasket 50. 3 has substantially the same configuration and function. Therefore, a detailed description is omitted except for differences.

  Specifically, the radiation detector module 5a according to the second embodiment further includes a gasket 50 on each of the four side surfaces. And in 2nd Embodiment, the groove | channel 50a is formed in the support body 2 of the part in which the gasket 50 is provided, and the gasket 50 is adhere | attached on the groove | channel 50a using adhesive members, such as a conductive double-sided tape. .

  Note that, unlike the sheet metal part 6 in the first embodiment, the sheet metal part 8 in the second embodiment surrounds the portion of the radiation detector stand 3a excluding the region where the gasket 50 is provided. For example, the width of the sheet metal part 8 is formed to be narrower than the width of the sheet metal part 6 in the first embodiment. The sheet metal part 8 and the gasket 50 surround the region of the radiation detector stand 3a that is substantially the same as the part surrounded by the sheet metal part 6. In addition, the sheet metal part 8 has a plurality of connection parts 8 a that are electrically connected to the pair of supports 2. The connection portion 8a is provided, for example, in a partial region of both end portions of the sheet metal portion 8 in front view and side view.

  The gasket 50 is formed having a conductive surface. The gasket 50 is formed using a material such as a sponge that is compressed by an external force. That is, the gasket 50 has a central member formed using a material that is compressed by an external force, and a surface layer that covers the surface of the central member and is formed using a material having electrical conductivity.

  Here, the gasket 50 is attached to a region including the side surface of the radiation detector module 5a corresponding to the boundary between the analog ground and the digital ground. That is, referring to FIG. 3, the gasket 50 is provided on the side surface of the radiation detector module 5a including the region through which the virtual line 200 of the mother board 2e that divides the region where the analog signal is handled and the region where the digital signal is handled. . The gasket 50 is electrically connected to an analog ground.

  Note that one gasket 50 provided on one side surface of the radiation detector module 5 a and a gasket 50 on the opposite side of the one gasket 50 are defined as one pair of gaskets 50. The other gasket 50 provided on the other side surface perpendicular to the one side surface and the gasket 50 on the opposite side of the other gasket 50 are defined as the other pair of gaskets 50. In this case, the position of one pair of gaskets 50 in the vertical direction and the position of the other pair of gaskets 50 in the vertical direction are such that one pair of gaskets 50 and the other pair of gaskets 50 handle analog signals. As long as the area is provided at a position including an area that divides the area where the digital signal is handled, it is not necessary to match.

  FIG. 4 shows an outline of a side view when a plurality of radiation detector modules according to the second embodiment of the present invention are arranged.

  When a plurality of radiation detector modules 5a are arranged, the gaskets 50 of the radiation detector modules 5a are in contact with each other. An analog ground is electrically connected between the radiation detector modules 5 a via the gasket 50. Thereby, it can suppress that a digital signal enters into the area | region where an analog signal is handled from the clearance gap between the radiation detector modules 5a. When a plurality of radiation detector modules 5a are arranged, the gaskets 50 of the radiation detector modules 5a are brought into contact with each other, and the radiation detector modules 5a are pressed against each other in a direction in which the gaskets 50 are crushed. The gap between the vessel modules 5a is reduced.

  While the embodiments of the present invention have been described above, the embodiments described above do not limit the invention according to the claims. In addition, it should be noted that not all the combinations of features described in the embodiments are essential to the means for solving the problems of the invention.

DESCRIPTION OF SYMBOLS 1 Radiation detector card 2 Support body 2a Wall 2b Groove 2c Indentation part 2d Flat surface 2e Mother board 2f Contact area 2g Screw hole 3, 3a Radiation detector stand 4 Connector 5 Radiation detector module 6 Sheet metal part 6a Connection part 7 Screw 8 Sheet metal portion 8a Connection portion 10 Semiconductor element 20 Substrate 22 Substrate terminal 30, 31 Card holder 32 Elastic member 34 Grooved hole 36 Protrusion portion 38 Terminal hole 40 Flexible substrate 50 Gasket 50a, 52a Groove 100 Radiation 200 Line 250 Electronic component

Claims (6)

A radiation detector card having a semiconductor element that outputs an analog signal in response to the incidence of radiation;
A pair of supports for supporting the radiation detector card at a portion including both ends of the radiation detector card; an analog ground for analog signals on the support side; and a mother board to which the pair of supports is fixed A radiation detector stand having:
A radiation detector module comprising: a sheet metal portion fixed to one support body and the other support body of the pair of support bodies and electrically connected to the analog ground. The motherboard has an electronic component that converts the analog signal into a digital signal and a digital ground for the digital signal on the side opposite to the side that supports the radiation detector card,
The radiation detector module according to claim 1, wherein the sheet metal part surrounds a region including a boundary between the analog ground and the digital ground, and a region including a part of the radiation detector card.   The radiation detector module according to claim 2, wherein surfaces of the mother boat that are in contact with the pair of supports are electrically connected to the pair of supports. The radiation detector card has a substrate on which the semiconductor element is mounted, and a support member that supports the substrate at a position away from an end of the semiconductor element,
The one support body is arranged at a predetermined interval corresponding to an interval at which the plurality of radiation detector cards are arranged, and a plurality of first grooves into which the plurality of radiation detector cards are inserted. Have
The other support has a plurality of second grooves into which the plurality of radiation detector cards are inserted, and is arranged in parallel with the one support. The radiation detector module according to claim 3. A gasket having a conductive surface and further compressed on the side by an external force,
The radiation detector module according to claim 4, wherein the gasket is attached to a region including the side surface corresponding to a boundary between the analog ground and the digital ground.   The radiation detector module according to claim 5, wherein the sheet metal part is wound around the radiation detector stand and fixed to the radiation detector stand.

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