JP2012138478A - Substrate for photoelectric conversion element and photoelectric conversion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce heat stress occurred in a substrate for a photoelectric conversion element.SOLUTION: A substrate for a photoelectric conversion element 10 of this invention includes: an insulation layer 4 made of a ceramic; and a first conductor layer 1 provided on an upper surface of the insulation layer 4 and on which a photoelectric conversion element 7 having electrodes on its upper surface and its lower surface is mounted. The first conductor layer has a mount region 112 to which the lower surface side electrode of the photoelectric conversion element 7 is connected, is made of a metal material, and includes carbon fiber. The substrate for the photoelectric conversion element 10 further includes a second conductor layer 2 which is provided on an upper surface of the first conductor layer 1 so as to enclose the mount region 112 and which is made of a metal material. The substrate for the photoelectric conversion element 10 achieves excellent heat and electricity transmission.

Description

  The present invention relates to a substrate for a photoelectric conversion element and a photoelectric conversion apparatus that can suppress the possibility of peeling of the photoelectric conversion element by improving heat dissipation.

  As a concentrating solar cell module including a photoelectric conversion element substrate on which a photoelectric conversion element is mounted, for example, an electrode plate described in Patent Document 1 and a photoelectric conversion element substrate including a support plate that supports the electrode plate It has been known.

  The concentrating solar cell module described in Patent Document 1 includes a solar cell that is a solar cell element, and gold (Au), silver (Ag), or copper (Cu) in which the lower surface of the solar cell is joined to the upper surface. An electrode plate made mainly of a metal having a high thermal conductivity such as, a solar cell bonded to the upper surface of the electrode plate, and an electric insulation bonded to the lower surface of the electrode plate to support the electrode plate And a support plate made of a thermally conductive material. In this concentrating solar cell module, the electrode plate and the support plate constitute a photoelectric conversion element substrate. In such a concentrating solar cell module, the electrode plate has a high thermal conductivity, thereby enhancing the heat dissipation of heat generated from the solar cells.

JP 2006-332535 A

  In the concentrating solar cell module described in Patent Document 1, heat generated in the solar cell is transmitted from the solar cell to the electrode plate, thereby improving heat dissipation. However, since an electrode plate mainly made of metal is used as the electrode plate in order to improve the heat dissipation of the heat generated in the solar cell, a large amount of heat is generated between the upper surface of the electrode plate and the lower surface of the solar cell. A differential expansion occurs. Therefore, a big thermal stress arises between a photovoltaic cell and an electrode plate, the adhesiveness between a photovoltaic cell and an electrode plate falls, and a photovoltaic cell may peel from an electrode plate. Thus, when a photovoltaic cell peels from an electrode plate, it is possible that the electroconductivity from a photovoltaic cell to an electrode plate falls. As a result, it is considered that the photoelectric conversion efficiency of the solar battery cell is lowered.

  An object of the present invention is to provide a photoelectric conversion element substrate capable of suppressing the possibility of the photoelectric conversion element peeling from the photoelectric conversion element substrate, and a photoelectric conversion device using the same, in order to solve the problems of the prior art. There is to do.

  A substrate for a photoelectric conversion element according to one aspect of the present invention includes an insulator layer made of ceramics, and a photoelectric conversion element having electrodes on the upper surface and the lower surface provided on the upper surface of the insulator layer, and photoelectric conversion A first conductor layer made of a metal material and containing carbon fiber, having a mounting region to which the lower surface side electrode of the element is connected, and provided on the upper surface of the first conductor layer so as to surround the mounting region; And a second conductor layer made of a metal material.

A photoelectric conversion device according to one aspect of the present invention includes a photoelectric conversion element substrate, a photoelectric conversion element mounted on the mounting region, and a photoelectric conversion element that is positioned on the photoelectric conversion element and transmits light from above. Condensing means for concentrating on the conversion element is provided.

  According to the substrate for a photoelectric conversion element based on one aspect of the present invention, the first conductor layer on which the photoelectric conversion element is mounted is made of a metal material and contains carbon fiber. The difference in thermal expansion between the photoelectric conversion element and the first conductor layer is reduced as compared with the case where the electrode plate is used for the photoelectric conversion element substrate. Therefore, thermal stress generated between the photoelectric conversion element and the first conductor layer can be reduced. Thereby, possibility that a photoelectric conversion element will peel from a 1st conductor layer can be reduced. Therefore, current and heat can be favorably transmitted from the photoelectric conversion element to the first conductor layer.

  Further, the second conductor layer made of a metal material constituting the photoelectric conversion element substrate is provided on the upper surface of the first conductor layer, so that the photoelectric conversion element flows to the first conductor layer. Current can be transferred to the second conductor layer. For this reason, the current flowing from the photoelectric conversion element to the first conductor layer can be satisfactorily taken out through the second conductor layer while maintaining good bonding between the photoelectric conversion element and the first conductor layer. Can do.

  And according to the photoelectric conversion apparatus based on 1 aspect of this invention, possibility that a photoelectric conversion element will peel from the board | substrate for photoelectric conversion elements can be suppressed.

It is sectional drawing which shows the photoelectric conversion apparatus of the example of the 1st Embodiment of this invention. It is sectional drawing which shows the photoelectric conversion apparatus in the modification of the example of the 1st Embodiment of this invention. It is sectional drawing which shows the photoelectric conversion apparatus in the modification of the example of the 1st Embodiment of this invention. It is a plane perspective view which shows the board | substrate for photoelectric conversion elements and the photoelectric conversion element in the photoelectric conversion apparatus of the example of the 1st Embodiment of this invention. It is a plane perspective view which shows the board | substrate for photoelectric conversion elements and the photoelectric conversion element in the photoelectric conversion apparatus of the modification of the example of the 1st Embodiment of this invention. It is sectional drawing which shows the photoelectric conversion apparatus of the example of the 2nd Embodiment of this invention.

  Hereinafter, some embodiments of the present invention will be described with reference to the drawings.

  As shown in FIGS. 1 and 4, a photoelectric conversion device 100 according to the first embodiment of the present invention is mounted on a photoelectric conversion element substrate 10 (hereinafter also simply referred to as a substrate 10) and an upper surface of the substrate 10. The photoelectric conversion element 7 is provided on the upper surface of the substrate 10, and the frame body 5 surrounds the photoelectric conversion element 7 when viewed in plan, and is held by the frame body 5 and above the photoelectric conversion element 7. And the light collecting means 6 located at the center.

  The substrate 10 of this example includes an insulator layer 4 made of ceramics, a first conductor layer 1 provided on the upper surface of the insulator layer 4 on which the photoelectric conversion element 7 is mounted, and a first conductive layer. And a second conductor layer 2 made of a metal material and provided on the upper surface of the body layer 1 so as to surround the photoelectric conversion element 7.

  The insulator layer 4 in the substrate 10 of this example has a square plate shape when viewed in plan. The insulator layer 4 is provided to electrically insulate the first conductor layer 1 from the first conductor layer 1 in the substrate 10 and a mounting substrate (not shown) on which the substrate 10 is mounted. Yes.

  The insulator layer 4 in the substrate 10 of this example is made of ceramics. As the ceramic used for the insulator layer 4, it is desirable to use a ceramic material having good thermal conductivity. Specifically, aluminum nitride (AlN) can be used as a ceramic material with good thermal conductivity.

  The thickness of the insulator layer 4 can be set to about 150 to 400 μm, for example. The vertical and horizontal dimensions of the insulator layer 4 can be set to about 5 to 50 mm, for example.

  The first conductor layer 1 in the substrate 10 of this example is provided on the upper surface of the insulator layer 4 and has a first part 11 and a second part 12 that are spaced apart from each other. Yes. The first part 11 has a mounting region 112 on the upper surface of which the photoelectric conversion element 7 is mounted, and is electrically connected to the lower surface side electrode of the photoelectric conversion element 7. The second portion 12 is electrically connected to the upper surface side electrode of the photoelectric conversion element 7. Further, the second part 12 has a recess 121 located so as to surround the mounting region 112 of the first part 11 when viewed in plan. The top surface of the first conductor layer 1 is flush with the mounting region 112 and the region where the second conductor layer 2 is provided.

  The first portion 11 in the first conductor layer 1 of this example has a quadrangular protruding portion 111 that protrudes toward the center of the substrate 10 in a part of the long side of the rectangle when viewed in plan. It is the provided shape. In addition, in this example, although the protrusion part 111 is formed in square shape, it is not restricted to this in particular, For example, you may form in semicircle shape or a triangle shape. The protrusion 111 has a mounting area 112 on the upper surface of which the photoelectric conversion element 7 is mounted.

  The second portion 12 in the first conductor layer 1 of this example is positioned so that the shape when viewed in plan surrounds the mounting region 112 of the first portion 11 in a part of the long side of the rectangle. This is a shape in which a recess 121 is provided. As shown in FIG. 4, the recess 121 of the second portion 12 is formed so as to surround the protruding portion 111 of the first portion 11 from three directions. In addition, in this example, although the recessed part 121 is formed in square shape, it is not restricted to this in particular, For example, you may form in semicircle shape or triangle shape.

  In addition, the thickness of the 1st site | part 11 and the 2nd site | part 12 in the 1st conductor layer 1 can be set to about 200-2000 micrometers, for example. Further, the first conductor layer 1 may be arranged such that part of the outer periphery of the first part 11 and the second part 12 coincides with the outer periphery of the insulating base 4 when viewed in plan. preferable. Thereby, the heat transferred from the photoelectric conversion element 7 to the first conductor layer 1 can be efficiently radiated to the outside without increasing the size of the substrate 10. The vertical and horizontal dimensions of the protrusion 111 can be set to about 3 to 10 mm, for example. In addition, it is preferable that the protrusion part 111 is located in the center of the board | substrate 10 when planarly viewed. Thereby, when heat is transmitted from the photoelectric conversion element 7, it is possible to reduce the possibility that the heat distribution is biased. The vertical and horizontal dimensions of the recess 121 can be set to, for example, about 3.5 to 10.5 mm.

  Like the substrate 10 of this example, it is preferable that the distance between the first portion 11 and the second portion 12 is constant. Thereby, when the protrusion part 111 is located in the inside of the recessed part 121, the protrusion part 111 and the recessed part 121 can be spaced apart by a fixed distance. Accordingly, when the first portion 11 and the second portion 12 are arranged at a distance necessary to maintain the electrical insulation between the first portion 11 and the second portion 12, the first portion 11 and the second portion 12 are arranged. It is possible to reduce the possibility that a portion that is unnecessarily wide separated between the protrusion 111 and the recess 121 is generated. As a result, the first portion 11 and the second portion 12 can be efficiently arranged on the upper surface of the insulator layer 4, so that the insulator layer 4 can be reduced in size. As a result, the substrate 10 can be reduced in size.

  The distance between the first part 11 and the second part 12 is preferably set to about 0.2 mm, for example. Thereby, the heat transfer from the photoelectric conversion element 7 to the second part 12 can be favorably performed while ensuring the electrical insulation between the first part 11 and the second part 12. . Thereby, for example, when the dimension of the photoelectric conversion element 7 is about 3 mm in length and width, the length and width of the substrate 10 can be reduced to, for example, about 5 mm.

  Further, since the mounting region 112 is provided in the protruding portion 111 surrounded by the second portion 12, various electrical connections between the upper surface side electrode of the photoelectric conversion element 7 and the second portion 12 are possible. It can be done from any direction. Specifically, if the shape of the protrusion 111 and the recess 121 when viewed in plan is a quadrangular shape as in this example, all three sides that are the outer sides of the protrusion 111 are Since the respective sides of the inner periphery face each other, the energization member 8 can be provided across the three sides of the protrusion 111. As a result, the design freedom of the upper surface side electrode of the photoelectric conversion element 7 mounted on the substrate 10 can be increased.

  As the 1st conductor layer 1 in the board | substrate 10 of this example, the composite material which consists of metal materials and contains carbon fiber is used. As the metal material used for the composite material, it is desirable to use a metal material having good thermal conductivity and electrical conductivity. Specifically, for example, copper (Cu), silver (Ag), aluminum (Al), or gold (Au) can be used as a metal material having good thermal conductivity and electrical conductivity.

  Thus, since the 1st conductor layer 1 in which the photoelectric conversion element 7 is mounted consists of metal materials and contains carbon fiber, compared with the case where it consists only of metal materials, a thermal expansion coefficient is set. Can be small. Therefore, thermal stress generated between the photoelectric conversion element 7 and the first conductor layer 1 can be reduced. Thereby, since possibility that peeling will arise between the photoelectric conversion element 7 and the 1st conductor layer 1 can be reduced, the adhesiveness between the photoelectric conversion element 7 and the 1st conductor layer 1 can be reduced. Can be prevented. Thereby, the heat generated in the photoelectric conversion element 7 can be satisfactorily transmitted to the second conductor layer 2.

  Furthermore, since the contained material is carbon fiber which is a conductive material, for example, unlike the case where the first conductor layer 1 contains an insulating material, good conductivity can be maintained. Thereby, a current can be favorably transmitted from the photoelectric conversion element 7 to the second conductor layer 2.

  In addition, as the carbon fiber to be contained, an aggregate of carbon fibers having a size of, for example, a thickness of about 5 to 10 μm and a length of about 100 to 500 μm can be used. The content of the carbon fiber contained in the first conductor layer 1 is preferably about 50 Vol%, for example. Thereby, electricity can be favorably conducted while reducing the difference in thermal expansion between the photoelectric conversion element 7 and the first conductor layer 1.

The second conductor layer 2 in the substrate 10 of this example is provided on the upper surface of the first conductor layer 1 so as to surround the mounting region 112. Here, “so as to surround the mounting region 112” does not necessarily mean that the mounting region 112 is completely surrounded by the second conductor layer 2. For example, a plurality of the second conductor layers 2 are included. These parts may be scattered around the mounting area 112. In this example, the second conductor layer 2 includes a third part 23 provided on the upper surface of the first part 11 and a fourth part 24 provided on the upper surface of the second part 12. And is formed by. The third portion 23 and the fourth portion 24 are separated from each other and are electrically insulated. The third portion 23 has a rectangular shape when viewed in plan. The shape of the fourth part 24 when viewed in plan is such that the short side of the outer periphery of the second part 12 is shortened and the recess 121 is enlarged. The substrate 10 is provided with the second conductor layer 2 so as to surround the mounting region 112, so that the heat dissipation generated in the photoelectric conversion element 7 is improved.

  In addition, the thickness of the 3rd site | part 23 and the 4th site | part 24 in the 2nd conductor layer 2 can be set to about 50-400 micrometers, for example. Further, the second conductor layer 1 is disposed so that a part of the outer periphery of the third portion 23 and the fourth portion 24 coincides with the outer periphery of the insulating base 4 when viewed in plan. preferable. Thereby, the heat transferred from the photoelectric conversion element 7 to the second conductor layer 2 can be efficiently radiated to the outside without increasing the size of the substrate 10.

  Moreover, it is preferable that the 3rd site | part 23 in the 2nd conductor layer 2 is spaced apart from the photoelectric conversion element 7 about 0.2 mm. Thereby, when the 3rd site | part 23 thermally expands, possibility that a thermal stress will be given to the photoelectric conversion element 7 can be reduced.

  Further, the fourth portion 24 in the second conductor layer 2 is separated from the first portion 11 in the outer periphery of the second portion 12 in the first conductor layer 1 with a certain interval. It is preferable to be provided on the peripheral side of the base body 10 as viewed from the photoelectric conversion element 7 by about 0.2 mm when viewed in plan from the portion. Thereby, when providing the 4th site | part 24, joining materials, such as a brazing material used for this, flowed in between the 1st site | part 11 and the 2nd site | part 12, and the 1st site | part 11 and the 2nd site | part It is possible to reduce the possibility of reducing the insulation between the portion 12.

  A metal material is used as the second conductor layer 2 in the substrate 10 of this example. As the metal material used for the second conductor layer 2, it is desirable to use a metal material having good thermal conductivity and electrical conductivity. Specifically, for example, copper (Cu), silver (Ag), aluminum (Al), or gold (Au) can be used as a metal material having good thermal conductivity and electrical conductivity. As described above, the second conductor layer 2 made of a metal material is provided on the upper surface of the first conductor layer 1, so that the electricity drawn from the photoelectric conversion element 7 to the first conductor layer 1 can be reduced. It can be transmitted through the second conductor layer 2 having better conductivity. Thereby, since the resistance value in the whole board | substrate 10 can be reduced, the heat_generation | fever in the board | substrate 10 by electricity flows can be reduced.

  When copper (Cu) and carbon fiber are used for the first conductor layer 1, it is desirable to use copper (Cu) for the second conductor layer 2 as well. As described above, since the same metal material is used in the first conductor layer 1 and the second conductor layer 2, the gap between the first conductor layer 1 and the second conductor layer 2 is the same. The difference in thermal expansion can be reduced.

  The thickness of the first conductor layer 1 in the substrate 10 of this example is larger than the thickness of the second conductor layer 2. Thereby, even if the 2nd conductor layer 2 thermally expands with the heat | fever transmitted from the photoelectric conversion element 7, possibility that a curvature will arise in the 1st conductor layer 1 can be reduced. This is because the first conductor layer 1 has a relatively large thickness, thereby improving the strength of the first conductor layer 1 and the second conductor layer 2 having a small thickness. This is because the thermal stress exerted on the first conductor layer 1 from the conductor layer 2 can be reduced. As a result, the reliability of the substrate 10 can be improved. For example, if the thickness of the first conductor layer 1 is about 1 mm, the thickness of the second conductor layer 2 is preferably about 0.2 mm.

  As shown in FIG. 1, the upper surface of the second conductor layer 2 is positioned closer to the mounting region 112 than the peripheral region 231 and the peripheral region 231 that are substantially parallel to the upper surface of the first conductor layer 1. And a nearby region 232 that gradually decreases toward the mounting region 112. Thereby, when thermal stress arises in the 2nd conductor layer 2, possibility that stress will concentrate on one place can be reduced. As a result, the reliability of the substrate 10 can be improved.

  Here, “substantially parallel” does not mean strictly parallel, but includes a deviation of the surface roughness of the first conductor layer 1 and the second conductor layer 2. Specifically, the ten-point average roughness on the upper surface of each of the first conductor layer 1 and the second conductor layer 2 is measured, and the first conductor layer 1 with respect to the second conductor layer 2 is measured. If the height of the slope is a deviation of this average roughness, it is considered to be substantially parallel.

  As the 2nd conductor layer 2 provided with the near field 232, the metal layer produced by plating, such as copper (Cu), can be used, for example. A metal layer obtained by polishing the corners of a metal plate such as copper (Cu) can also be used as the second conductor layer 2.

  Further, the neighboring region 232 in the second conductor layer 2 of the present example has a curved surface that expands toward the upper surface, for example, as shown in FIG. 2 or is inclined as shown in FIG. It is preferable to have an inclined surface. Thereby, a part of the light hitting the vicinity region 232 can be reflected toward the mounting region 112. As a result, the photoelectric conversion efficiency of the mounted photoelectric conversion element 7 can be improved.

  As the dimensions of the inclined surface, for example, the width is set to about 0.1 to 0.5 mm, the height is set to about 50 to 400 μm, and the angle is set so that the neighboring region 232 is inclined about 60 to 80 degrees when viewed from the peripheral region 231. can do.

  A method for manufacturing the substrate 10 of this example will be described. First, the insulator layer 4 is prepared. In this example, an aluminum nitride (AlN) plate is used as the insulator layer 4. The dimensions of the aluminum nitride (AlN) plate are, for example, a thickness of about 0.3 to 0.5 mm and a vertical and horizontal dimension of about 100 mm. An adhesive metallization layer is formed on the upper surface of an aluminum nitride (AlN) plate.

  Next, the 1st conductor layer 1 is produced. The following method can be used for producing the first conductor layer 1. First, a plate-like lump in which a bundle of unidirectional carbon fibers is bonded with carbon is crushed into small aggregates made of unidirectional carbon fibers, and the crushed aggregates are collected to form a solid pitch or coke. Immerse in a solution of thermosetting resin such as phenol resin in which fine powder is dispersed. In addition, the magnitude | size of the aggregate | assembly obtained by crushing a plate-shaped lump is about 0.1-1 mm about one side, when the shape is seen as a substantially cube, for example.

  Next, this is dried, a predetermined pressure is applied and heated to cure the thermosetting resin portion, and a plate-like lump is obtained. This is fired at a high temperature in an inert atmosphere to carbonize the phenol resin and pitch or coke fine powder to obtain a carbonaceous base material. Next, a metal having a thermal conductivity, in this example, copper (Cu), is melted and impregnated in a carbonaceous base material under high temperature and high pressure. The impregnated copper (Cu) becomes a copper lump and is dispersed in the carbonaceous base material. As the metal to be impregnated, for example, silver (Ag), aluminum (Al), nickel (Ni), or magnesium (Mg) can be used in addition to copper (Cu). And the board | plate which becomes the 1st site | part 11 and the 2nd site | part 12 is produced by cutting out the lump which disperse | distributed carbon fiber and copper (Cu) in the carbonaceous preform | base_material in plate shape. As for the dimensions of the plate, for example, the thickness is about 0.5 to 2 mm, the vertical and horizontal dimensions are about 25 mm for the long side of the first part 11, and about 12 mm for one side of the protrusion 111 of the first part 11.

  Next, the first conductor layer 1 is bonded to the upper surface of the insulator layer 4. In the bonding, the metallized layer of the insulator layer 4 and the lower surface of the first conductor layer 1 are bonded. For joining, for example, a brazing material such as silver brazing can be used.

Further, the second conductor layer 2 is formed on the upper surface of the first conductor layer 1. As the second conductor layer 2, a copper plate is used in this example. By applying a brazing material such as silver brazing to the region where the second conductive layer 2 is provided on the upper surface of the first conductive layer 1, and bonding a copper plate as the second conductive layer 2 to this. The substrate 10 is used.

  In this example, a copper plate is used as the second conductor layer 2. However, the present invention is not limited to this, and other metal plates such as iron (Fe) may be used. Furthermore, as the second conductor layer 2, plating such as copper plating can be used.

The photoelectric conversion element 7 is, for example, a solar cell element that includes a III-V group compound semiconductor. The photoelectric conversion element 7 can convert received light energy into electric power and output it by the photovoltaic effect. The photoelectric conversion element 7 of this example is mounted on the mounting region 112 of the first conductor layer 1. As the photoelectric conversion element 7, an element having electrodes on the upper surface and the lower surface can be used. The lower surface side electrode and the first portion 11 in the first conductor layer 1 are joined by a brazing material such as silver brazing. The upper surface side electrode and the fourth portion 24 in the second conductor layer 2 are electrically joined by the energizing member 8.

  A bonding wire can be used as the energizing member 8. The bonding wire may be provided across only one side of the protruding portion 111, or may be provided across two opposite sides as shown in FIG. In this way, the bonding wire is provided across the two opposite sides, so that the fourth portion 24 can be connected via the bonding wire as compared with the case where the bonding wire is provided so as to straddle only one side. The bias of the transmitted heat can be reduced.

  2 and 3, the peripheral region 231 that is substantially parallel to the upper surface of the first conductor layer 1 and located closer to the mounting region 112 than the peripheral region 231 toward the mounting region 112. When the cross section of the vicinity region 232 has a shape that reflects light toward the mounting region 112, the bonding wire is preferably bonded to the peripheral region 231. . Thereby, it is possible to make it difficult for the bonding wire to block the light traveling toward the vicinity region 232 and the light traveling from the vicinity region 232 toward the mounting region 112.

  The photoelectric conversion element 7 has, for example, an InGaP / GaAs / Ge three-junction cell structure. The indium gallium phosphide (InGaP) top cell converts energy contained in a wavelength region of 660 nm or less. A gallium arsenide (GaAs) middle cell converts energy contained in a wavelength region from 660 n to 890 nm. The germanium (Ge) bottom cell converts light contained in a wavelength region from 890 nm to 2000 nm. The three cells are connected in series via a tunnel junction. The open circuit voltage is the sum of the electromotive voltages of the three cells.

  The lower surface side electrode and the upper surface side electrode of the photoelectric conversion element 7 are formed on the lower surface and the upper surface of the photoelectric conversion element 7. The lower surface side electrode and the upper surface side electrode are made of, for example, silver (Ag), aluminum (Al), or the like.

  The frame 5 in the photoelectric conversion device 100 of this example is joined to the upper surface of the second conductor layer 2. The frame 5 in this example has a cylindrical shape when viewed in plan, and is provided so as to surround the photoelectric conversion element 7.

The frame 5 in the photoelectric conversion device 100 of this example is made of ceramics. As the ceramic used for the frame 5, it is desirable to use a ceramic material having good thermal conductivity. Specifically, for example, aluminum nitride (AlN) can be used as a ceramic material having good thermal conductivity. A metallized layer is formed on the lower surface of the frame 5 in order to improve the bondability with the second conductor layer 2. For joining the frame 5 and the second conductor layer 2, a brazing material such as silver brazing can be used. The frame 5 in this example is made of ceramics, so that electrical insulation is improved.

  A metal material can also be used for the frame 5. As the metal material, for example, an iron nickel cobalt (Fe—Ni—Co) alloy can be used.

  The condensing means 6 in the photoelectric conversion device 100 of this example is provided so as to be positioned on the photoelectric conversion element 7. The condensing means 6 is provided for the purpose of concentrating light from above on the photoelectric conversion element 7. The light collecting means 6 is joined to the frame body 5. For joining the light collecting means 6 and the frame 5, for example, a glassy material can be used. In addition, as the condensing means 6, a condensing prism can be used, for example.

  Next, the photoelectric conversion apparatus 100 of the example of the 2nd Embodiment of this invention is demonstrated. In addition, in each structure of this example, about the member which has the structure and function similar to 1st Embodiment, the same referential mark is attached | subjected and the detailed description is abbreviate | omitted.

  As shown in FIG. 6, the photoelectric conversion device 100 of the example of the second embodiment is different in the configuration of the substrate 10 from the photoelectric conversion device 100 of the example of the first embodiment. Specifically, the third conductor layer 3 is provided on the lower surface of the insulator layer 4.

  The third conductor layer 3 in the substrate 10 of this example is formed so as to surround the mounting region 112 when seen in a plan view. As the third conductor layer 3, it is desirable to use a metal material having good thermal conductivity. Specifically, for example, copper (Cu), silver (Ag), aluminum (Al), or gold (Au) can be used as a metal material having good thermal conductivity. As described above, the third conductor layer 3 made of a metal material is provided on the upper surface of the insulator layer 4, so that the thermal expansion difference between the first conductor layer 1 and the second conductor layer 2. Even if a force to warp the substrate 10 is generated by the third conductive layer 3, a force to warp the substrate 10 in the opposite direction is exerted by the third conductor layer 3, so that both forces cancel each other. become. Thereby, the curvature which arises in the board | substrate 10 can be reduced.

  Furthermore, since the third conductor layer 3 is formed so as to surround the mounting region 112, it is possible to make it difficult for thermal stress to be generated immediately below the mounting region 112 on which the photoelectric conversion element 7 is mounted. . Thereby, possibility that the photoelectric conversion element 7 and the board | substrate 10 will peel can be reduced.

  The third conductor layer 3 has, for example, a frame shape, and preferably has an inner diameter and an outer diameter that coincide with the second conductor layer 2 when viewed in cross section. Thereby, generation | occurrence | production of a thermal stress can be reduced more effectively.

  Note that a plurality of metal plates projecting downward may be added to the third conductor layer 3, and thus, the third conductor layer 3 can also be used as a heat radiating fin. As such a metal plate, for example, nine copper (Cu) plates having a thickness of about 1 mm and a length and width of about 5 mm can be used as a heat radiation fin. When copper (Cu) is used as the material for the third conductor layer 3, it is desirable to use copper (Cu) also for the metal plate for the radiation fin. Thereby, the thermal expansion difference which arises between a radiation fin and the 3rd conductor layer 3 can be reduced.

  It should be noted that the present invention is not limited to the above-described embodiments, and various modifications and combinations of embodiments may be made without departing from the scope of the present invention.

1: first conductor layer 112: mounting region 2: second conductor layer 231: peripheral region 232: neighboring region 3: third conductor layer 4: insulator layer 6: light collecting means 7: photoelectric conversion Element 8: Current-carrying member 10: Substrate for photoelectric conversion element 100: Photoelectric conversion device

Claims (6)

An insulator layer made of ceramics;
A carbon fiber made of a metal material having a mounting region provided on the upper surface of the insulator layer, on which a photoelectric conversion element having electrodes on the upper surface and the lower surface is mounted and to which a lower surface side electrode of the photoelectric conversion element is connected A first conductor layer contained;
A photoelectric conversion element substrate comprising: a second conductor layer made of a metal material provided on an upper surface of the first conductor layer so as to surround the mounting region.   2. The photoelectric conversion element substrate according to claim 1, wherein a thickness of the first conductor layer is larger than a thickness of the insulator layer and the second conductor layer.   The top surface of the first conductor layer is a plane in which the mounting region and the region where the second conductor layer is provided are parallel or flush with each other, and the top surface of the second conductor layer is A peripheral region that is substantially parallel to the top surface of the first conductor layer, and a neighboring region that is located closer to the mounting region than the peripheral region and gradually decreases toward the mounting region. The photoelectric conversion element substrate according to claim 1.   The photoelectric conversion element substrate further includes a third conductor layer on a lower surface of the insulating base, and the third conductor layer surrounds the mounting region when seen in a plan view. The substrate for photoelectric conversion elements according to claim 1.   The photoelectric conversion element substrate according to any one of claims 1 to 4, a photoelectric conversion element mounted on the mounting region, and light from above located on the photoelectric conversion element to the photoelectric conversion element A photoelectric conversion device comprising a condensing means for concentrating.   The photoelectric conversion device according to claim 5, wherein the photoelectric conversion element is electrically connected to the peripheral region of the second conductor layer via an energization member.

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