JP2002289901A - Mounting structure for photovoltaic element, and mounting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simple mounting structure and amounting method for a photovoltaic element, which can provide a photoelectric device such as a solar cell system, etc., at a low cost. SOLUTION: In the mounting structure for the photovoltaic element which possesses a photovoltaic element, having an electrode at a non-light-receiving face and a metal body for extracting the power generated by that photovoltaic element from/that photovoltaic element, that photovoltaic element is mounted on the first face of that metal body, and electrically insulated junction material is jointed to the second face.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photoelectric device such as a solar cell or a photoelectric sensor, and more particularly, to a mounting structure and a mounting method of a photovoltaic element.

[0002]

In recent years, and global warming due to the increase in the greenhouse effect that is CO ₂ becomes a problem, demand for clean sources of energy development that do not emit CO _2, has been increasingly. Nuclear power generation is one of such energy sources, but there are many problems that must be solved, such as the problem of radioactive waste, and the demand for providing a safer and cleaner energy source is increasing.

For these reasons, among the clean energy sources expected in the future, a solar cell using a photovoltaic element has attracted much attention in terms of its cleanness, high safety, and easy handling. Have been.

At present, many solar cells have been proposed,
Some of them are actually used as power sources.
Such solar cells are roughly classified into a crystalline solar cell using single crystal silicon or polycrystalline silicon, an amorphous solar cell using amorphous silicon, and a compound semiconductor solar cell. Also, depending on the type of installation, for example, Japanese Patent Application Laid-Open
-82820, a frame solar cell disclosed in
For example, a frameless solar cell disclosed in JP-A-7-131048, for example, a roof material-integrated solar cell disclosed in JP-A-8-177187 and JP-A-11-97727, for example, JP-A-9-197 It is classified into a concentrating solar cell and the like as disclosed in JP-A-83006.

[0005] In the above-mentioned solar cell, the material cost of the cells (photovoltaic elements) constituting the solar cell accounts for the largest proportion of the cost. It is necessary to reduce the amount of materials used for photovoltaic elements. Concentrating solar cells are
In order to reduce power generation costs by effectively utilizing the capability of expensive photovoltaic elements, sunlight is concentrated several times to several hundred times by a lens, and the amount of light incident on the photovoltaic elements of the solar cell is reduced. By increasing it, the usage of the photovoltaic element is reduced as much as possible.

In the device disclosed in Japanese Patent Application Laid-Open No. Hei 9-83006, a solar cell such as arsenic gallium is disposed on a supporting substrate such as glass, resin material or ceramics, and the solar cell is directed upward from the solar cell. A tapered concave portion having a large opening area is provided, and a high-refractive-index light collecting structure made of polystyrene or the like and having a surface processed into a lens shape is arranged in the concave portion.

Japanese Patent Application Laid-Open No. 7-231111 discloses an example of a concentrating solar cell substrate. A small solar cell with a side of about 2 mm is connected to a standard IC type carrier such as a dual in-line package, and the carrier is attached to a printed circuit board such as a through-hole board, so that electrical connection is made. ing.

The structure of a generally known high-concentration solar power generation system will be described with reference to FIG. FIG. 13A is a schematic diagram illustrating an appearance of a concentrating solar power generation system,
FIG. 13B is a schematic diagram illustrating a concentrating solar cell module of the concentrating solar power generation system, and FIG.
(C) is a schematic diagram when the periphery of the photovoltaic element of the concentrating solar cell module is viewed from the light receiving surface. This concentrating solar power generation system includes a tracking device 10 that tracks the movement of the sun.
9, a high-concentration solar cell module 115
Are arranged in 5 rows × 4 rows, and the power generated by the high-concentration solar cell module is taken out to the outside using the lead wire 108.

Each of the concentrating solar cell modules is generated by a photovoltaic element via a photovoltaic element 100 mounted on a circuit board 101 and a circuit pattern 104 formed on the circuit board 101. Extraction electrode 106 and lead wire 108 for extracting the discharged power out of the module
A heat sink 103 adhered to the circuit board via a silver paste 102 to prevent remarkable heating of the photovoltaic element due to the condensing of sunlight; A Fresnel lens 110 for condensing light on the element 100 is provided.

A photovoltaic element used in a concentrating solar cell module and a method of mounting the photovoltaic element on a circuit board will be described with reference to FIGS.

FIG. 15 is an external view showing an example of a photovoltaic element used in a concentrating solar cell, and FIG. 15A is a schematic external view of a photovoltaic element made of a single crystal as viewed from a light receiving surface. FIG. 15B is a schematic view of the first side of the photovoltaic element, FIG. 15C is a schematic view of the second side of the photovoltaic element, and FIG. It is the external appearance schematic diagram which looked at the photovoltaic element from the non-light-receiving surface side.

In FIG. 15, reference numeral 121 denotes 12 mm square, thickness 125
This is a photovoltaic element made of a single crystal of μm, and a texture structure and an antireflection film are formed on a sunlight receiving surface thereof. Reference numerals 122 and 123 denote a pair of extraction electrodes provided on the non-light-receiving surface of the photovoltaic element, each having a thickness of 10 μm connected to the p-pole and the n-pole of the photovoltaic element.
Au having a thickness of about 0.01 μm is deposited on the m Al electrodes.

A photovoltaic element used in a concentrating solar cell is required to efficiently irradiate the photovoltaic element with sunlight having a high degree of condensing, and the active area of the photovoltaic element must be increased. In order to approach 100% as much as possible, the extraction electrode is generally provided on the non-light receiving surface of the cell.

The concentrating solar cell having an electrode on the non-light receiving surface is mounted on a supporting substrate made of glass, a resin material, ceramics, or the like. An example of a solar cell mounted on a supporting substrate will be described with reference to FIGS.

In FIG. 16A, reference numeral 101 denotes a circuit board having a predetermined circuit pattern, which is usually formed on a supporting board having a thickness of about 0.5 to 1 mm and having a low thickness of about 0.01 to 1 mm. A circuit pattern 104 made of a resistive material is formed.
₂ O ₃ ceramic respective thickness 0.3mm on both sides, 0.
25mm oxygen-free copper foil was applied to Direct Bond Co.
A substrate bonded by a copper method and having a circuit pattern formed on a 0.3 mm thick copper foil was used. Reference numeral 105 denotes a bonding material for bonding the photovoltaic element and the extraction electrode to the circuit board. Generally, various solders and carbon sheets are used. A solder paste having a tin-lead eutectic composition is screen-printed with a metal plate to a thickness of 120 μm on the electrodes (not shown in FIG. 16) corresponding to the extraction electrodes 122 and 123 and the locations where the extraction electrodes are to be arranged. Printed.

FIG. 16B shows a state where the photovoltaic element 100 is arranged on the cream solder 105 of the circuit board 101 and the extraction electrode 106 is arranged on the circuit pattern 104. Fig. 13 shows the concentrating solar cell module.
As shown in (1), the relative position between the photovoltaic element and the Fresnel lens is important for effectively utilizing the collected sunlight. Therefore, it is required that the photovoltaic element and the circuit board, the circuit board and the support casing of the Fresnel lens, and the support casing and the Fresnel lens are arranged at appropriate positions. Further, the extraction electrode 106 is required to extract the electric power generated by the photovoltaic element 100 to the outside without resistance loss. Here, the thickness is 0.7 mm, the width is 15 mm, and the length is 75 m.
m of oxygen-free copper foil is used.

In FIG. 16 (3), the photovoltaic element 100,
Circuit board 10 in a state in which
1 is cooled by melting the cream solder 105 and then cooling, so that the photovoltaic element 100 and the extraction electrode 106 are cooled.
Is mounted on a circuit board. The heating conditions vary depending on the composition of the cream solder 105 to be used, but in the case of a solder having a tin-lead eutectic composition, it is necessary to heat the solder to a temperature of 195 ° C. or higher for at least 2 to 5 seconds.

In FIG. 16D, the extraction electrode 106
2 shows a state in which, for example, a further lead wire 108 is connected by soldering or the like in order to connect to an extraction electrode of an adjacent concentrating solar cell module. The lead wire 10
Similarly to the extraction electrode 106, it is required to connect the power generated by the photovoltaic element to the outside without resistance loss, and here, a copper wire of φ3 mm and length of 350 mm is used.

FIG. 17 (5) shows a state where the circuit board 101 and the heat sink 103 are fixed using the silver paste 102. In the concentrating solar cell, it is necessary to efficiently radiate the heat of the photovoltaic element 100 heated by the condensing with a radiator such as the heat sink 103. For the part, a known silver paste having a thermal conductivity of, for example, 1 W / m · K or more is suitably used. Here, ABLEBOND 84-1LMI-
T1 was used. The silver paste is adhered to the heat sink by a known method such as printing.
After uniformly applying 35 mm, the circuit board 101 on which the photovoltaic element 100 is mounted is arranged in the paste form,
Bonding is performed by heating and curing in an oven at a temperature of 1 hour.

FIGS. 17 (6) and (7) show a concentrating solar cell module produced using the above-described method and material. FIG. 17 (6) is a front view of the module, and FIG.
7 (6) is a perspective view.

[0021]

However, in the photovoltaic element mounting form shown in FIGS. 16 and 17, the substrate on which the photovoltaic element is mounted is a component that is similar to or more expensive than the photovoltaic element. Therefore, there is a problem that the cost of the concentrating solar cell is hindered from being reduced.

In the embodiment of mounting the photovoltaic element shown in FIGS. 16 and 17, a step of mounting the photovoltaic element on a substrate, and a step of bonding the substrate on which the photovoltaic element is mounted and a heat sink with a silver paste However, there is a problem that each step has a heating step, and the time of each step is long and the manufacturing cost is high.

Further, it is necessary to put the substrate on which the photovoltaic element is mounted in an oven at 150 ° C. in order to cure the silver paste.

When a ceramic substrate is used as a circuit board, cracks may occur in the ceramic layer in the circuit board due to, for example, thermal cycling. When a crack occurs in the circuit board, the heat conduction of the crack portion is extremely reduced, and the heat of the photovoltaic element cannot be sufficiently dissipated. Further, melting of the solder for joining the photovoltaic element and the circuit board, and failure of the photovoltaic element due to heat may be considered.

In the mounting method of the photovoltaic element mounting form shown in FIGS. 16 and 17, since each material is individually supplied, batch processing is required, and an expensive manufacturing apparatus is required. Was.

An object of the present invention is to solve the above-mentioned problems in the prior art and to provide a mounting structure and a mounting method of a photovoltaic element capable of reducing the manufacturing cost of a photoelectric device such as a solar cell.

[0027]

SUMMARY OF THE INVENTION The present invention, which achieves the above object, provides a mounting structure and a mounting method for a photovoltaic element having the following configuration.

According to a first aspect of the present invention, there is provided a photovoltaic device having an electrode on a non-light receiving surface, and a device for generating electric power generated by the photovoltaic device outside the photovoltaic device. In a mounting structure of a photovoltaic element including a metal body for taking out the metal body, the photovoltaic element is bonded to a first surface of the metal body, and an electrically insulating bonding material is bonded to a second surface. It is characterized by.

Here, the first surface of the metal body refers to one surface of the metal body, and the second surface of the metal body refers to a surface opposite to the first surface of the metal body.

According to this structure, the metal body can serve as a heat spreader and have a heat radiation function, and a large current can be easily taken out by the metal body. Further, the metal body needs to be electrically separated for each electrode of the photovoltaic element, for example, by fixing a metal body having the photovoltaic element mounted on a radiator, cutting off a part of the metal body,
The metal body is divided into a plurality of electrically separated electrodes, and the electrically insulating bonding material provided on the second surface of the metal body ensures insulation between the plurality of substantially separated electrodes.

According to a second aspect of the present invention, in the photovoltaic element mounting structure according to the first aspect, the metal body is at least one of gold, silver, copper, aluminum, nickel, iron, cobalt, and tungsten. Alternatively, a preferred embodiment includes those alloys as main components.

According to this configuration, the metal body has high conductivity, and can be preferably used as an external extraction electrode.

That is, for example, a photovoltaic element used for a concentrating solar cell generates a current of 1 A or more.
An electrode for taking out the electric power generated by the photovoltaic element to the outside is required to have high conductivity such that the electric resistance loss is 5% or less. Such a configuration is preferred because it is necessary to have a cross-sectional area.

The third aspect of the present invention is the first or second aspect.
In a preferred embodiment, the metal body has a plate-like shape having a thickness of 0.05 to 2 mm.

According to such a configuration, the metal body is also a preferable configuration as a support for the photovoltaic element.

That is, a thin photovoltaic element having an electrode on a non-light-receiving surface used in a concentrating solar cell requires a support material. The metal body is required to have rigidity also serving as a support material for the photovoltaic element, and the thickness is desirably 0.05 mm or more.If a thick metal body is used, after the photovoltaic element and the metal body are joined together, In actual use, due to the difference in the coefficient of thermal expansion of each material, defects such as peeling of the bonding surface and cracking of the photovoltaic element may occur.
mm or less is desirable.

The invention described in claim 4 is the first to third aspects of the present invention.
In the mounting structure of the photovoltaic element according to any one of the above, it is preferable that the metal body has a shape capable of mounting a plurality of photovoltaic elements on the same frame.

In this case, it is possible to continuously supply a roll-shaped metal body provided with a predetermined pattern on the metal body, to continuously mount the photovoltaic elements on the metal body, and then to separate them individually. it can. That is, since the metal body has a shape that allows a plurality of cells to be mounted on the same frame, by providing notches or holes at intervals corresponding to the feed structure of the mounting device at the longitudinal end of the metal body, continuous As a result, throughput can be improved, manufacturing costs can be reduced, and existing mounting devices can be used.

The invention according to claim 5 is the invention according to claims 1 to 4
In the mounting structure of the photovoltaic element according to any one of the above, the electrical connection between the photovoltaic element and the metal body includes a bonding material containing at least any one of tin, lead, silver, and copper Is included as a preferred embodiment.

In this case, the electrode of the photovoltaic element and the metal body are joined by the above-mentioned paste-like joining material containing a metal filler and then heated or cured by heating. Conductivity can be obtained.

The invention described in claim 6 is the first to fifth aspects of the present invention.
In the mounting structure of the photovoltaic element according to any one of the above, it is preferable that the electrically insulating bonding material contains a thermally conductive adhesive material.

The above-mentioned electrically insulating bonding material ensures insulation between the metal body and the radiator. However, it is necessary to efficiently release the heat generated in the photovoltaic element to the radiator, and has a heat conductivity. When the adhesive is contained, the joining of the metal body on which the photovoltaic element is mounted and the radiator can be performed in a short time, so that the manufacturing process of the photovoltaic element can be simplified.

The invention according to claim 7 is the invention according to claims 1 to 6
In the mounting structure of the photovoltaic element according to any one of the above, it is preferable that the electrically insulating bonding material is a double-sided adhesive insulating sheet having thermal conductivity.

In this case, it is not necessary to separately provide a metal body on which the photovoltaic element is mounted and a radiator, which is usually a metal body, so that a mounting structure of the photovoltaic element having a simple mounting structure can be provided.

The invention described in claim 8 is the invention according to claims 1 to 7
In the mounting structure of the photovoltaic element according to any one of the above, the second surface of the metal body preferably includes bonding a radiator via an electrically insulating bonding material.

According to such a configuration, the heat radiation efficiency can be significantly improved.

According to a ninth aspect of the present invention, in the mounting structure of the photovoltaic element according to the eighth aspect, it is preferable that the radiator has at least one flat surface. Including.

In this case, it is easy to join with the above-mentioned heat-adhesive sheet. A radiator such as a heat sink is the cheapest natural air-cooled device and can provide a simple photovoltaic element mounting structure, so that there is little fear of failure.

According to a tenth aspect of the present invention, in the mounting structure of the photovoltaic element according to the eighth or ninth aspect, the radiator has a long shape on which at least two photovoltaic elements can be mounted. This is included as a preferred embodiment.

In this case, since the long radiator can be used as a support for a metal body in which a plurality of photovoltaic elements are mounted on the same frame, the plurality of photovoltaic elements are made into one unit. Easy to handle in case.

According to an eleventh aspect of the present invention, there is provided a photovoltaic device having an electrode on a non-light receiving surface,
A metal body for extracting power generated by the photovoltaic element out of the photovoltaic element, and a method for mounting a photovoltaic element including a radiator for radiating heat generated by light reception, At a predetermined position on the first surface of the metal body, an element bonding step of bonding the photovoltaic element with a bonding material, and at a predetermined position on the second surface of the metal body, a radiator with an electrically insulating bonding material. And a radiator bonding step of bonding.

According to such a mounting method, the mounting structure of the photovoltaic element described above can be realized.

According to a twelfth aspect of the present invention, in the method for mounting a photovoltaic element according to the eleventh aspect, the radiator bonding step is performed after the element bonding step. At a predetermined position on the first surface of the metal body,
Arranging a bonding material, and arranging the photovoltaic element at a predetermined position where the bonding material on the metal body is arranged,
Bonding the metal body and the photovoltaic element with the bonding material by heating, at least, in the radiator bonding step, an electrically insulating bonding material is provided at a predetermined position on the radiator. Arranging, and arranging, on an electrically insulating bonding material provided at a predetermined position on the radiator, a metal body to which the photovoltaic element is bonded in a state where the second surface side is bonded; A step of joining the metal body and the radiator by pressing from the upper surface of the electromotive element, as a preferred embodiment.

According to such a mounting method, a known mounting device such as an existing dispenser, screen printer, chip mounter, reflow furnace, or the like can be used in combination.

According to a thirteenth aspect of the present invention, in the method for mounting a photovoltaic element according to the twelfth aspect, the metal body is a lead frame, and the lead frame is continuously supplied in the element bonding step. In a preferred embodiment, the method further comprises the step of joining the photovoltaic elements to the lead frame at regular intervals and separating the lead frames individually after the element joining step.

According to such a mounting method, mounting of the photovoltaic element on the metal body can be significantly simplified. Since continuous supply is possible, it is possible to respond to mass production. Mounting process that enables continuous transfer of bonding material printing / dispenser process, chip mounter process, and reflow process by providing notches at equal intervals at the ends of the lead frame corresponding to the transport system of the chip mounter manufacturing equipment Can be set. Further, since an existing manufacturing apparatus such as a chip mounter can be used, an expensive manufacturing apparatus is not required.

According to a fourteenth aspect of the present invention, in the method of mounting the photovoltaic element according to the twelfth or thirteenth aspect, the pressing means used for pressing in the radiator bonding step is a portion expanded by gas injection. In a preferred embodiment, the pressing is performed by the expanding portion.

According to such a mounting method, the metal body on which the photovoltaic element is mounted is pressed without destroying the photovoltaic element, and the metal body is fixed to the radiator with an electrically insulating bonding material. Can be.

According to a fifteenth aspect of the present invention, there is provided the photovoltaic device mounting method according to the eleventh aspect, wherein the element bonding step is performed after the radiator bonding step. Includes a step of bonding the radiator on the second surface of the metal body via the electrically insulating bonding material, and in the element bonding step, at a predetermined position on the first surface of the metal body. Arranging a bonding material, arranging the photovoltaic element at a predetermined position on the metal body where the bonding material is arranged, and heating the metal body and the photovoltaic element with the bonding material. And a step of joining at least the following.

In this case, after the radiator is bonded to the metal body, the element is bonded. Therefore, when the element is mounted on the metal body, the radiator may be used as a support for the metal body and the element. it can.

[0061]

Embodiments of the present invention will be described below.

(Photovoltaic Element) As the photovoltaic element in the present invention, a thin semiconductor element having an electrode on a non-light receiving surface used for a concentrating solar cell can be suitably applied. However, the present invention is also applicable to a photoelectric device using a photovoltaic element such as a photoelectric sensor other than a solar cell. Semiconductor materials for photovoltaic devices include single crystal silicon, polycrystalline silicon, amorphous silicon, arsenic gallium, aluminum-gallium arsenide, indium phosphide,
Group III-V compound semiconductors such as gallium-indium phosphide are preferably used.

In the case of a photovoltaic element in which an electrode is formed on the non-light receiving surface side, it is required that the element be particularly thin in order to provide a pn junction on the non-light receiving surface side of the element, and an element having a thickness of 200 μm or less is suitably used. it can. An electrode made of a known electrode material such as gold, silver, aluminum, nickel, or copper, which is electrically connected to the pn junction, is provided on the non-light-receiving surface of the photovoltaic element by a known means such as evaporation or sputtering. It has been. In addition, as a method of forming a crystalline thin film element, a known method such as a method of performing polishing after cutting out from a silicon ingot with a wire saw or a method of silicon-on-insulator (SOI) can be applied.

(Metal Body) The metal body in the present invention also serves as a support member for supporting the photovoltaic element, and also serves as an electrode for taking out the electric power generated by the photovoltaic element to the outside of the module. It is. Copper, silver,
A known electric conductive material containing any of aluminum, nickel, iron, tungsten, etc., or an alloy thereof as a main component can be suitably applied, and gold, silver, aluminum can be applied to a desired place as necessary, for example, to prevent oxidation. , Nickel, tin,
Surface treatment such as lead is performed. In addition, excellent bonding (soldering) properties and bonding properties, and high thermal conductivity for releasing heat generated in the photovoltaic element are required.

The photovoltaic element mounting portion to which the photovoltaic element on the first surface side of the metal body is joined is provided with a rectified or electromotive current by the photovoltaic element to take it out of the semiconductor element. A circuit pattern corresponding to the electrode shape of the photovoltaic element is provided. As a method for forming the circuit pattern on the metal body, a known method such as etching or die cutting can be used.

At least the photovoltaic element mounting portion of the metal body conforms to the planar shape of the photovoltaic element, for example, as a plane.

Further, the metal body may have a shape such as a lead frame that is continuously supplied in a roll shape, for example, and a plurality of photovoltaic elements can be mounted on the same frame at equal intervals.

Further, the metal body must be electrically separated for each electrode of the photovoltaic element. For example, after fixing the metal body to which the photovoltaic element is joined on a radiator, a part of the metal body is fixed. It is necessary to divide the metal body into a plurality of electrically separated electrodes by cutting the metal body with a press cutter or the like.

(Heat radiator) The heat radiator in the present invention is for radiating the heat generated in the photovoltaic element by the light collection. In a concentrating solar cell module, sunlight is concentrated several times to several hundred times by a lens, so the temperature of the concentrated part rises remarkably and sometimes reaches several hundred degrees. Need to escape. In order to improve the characteristics of the radiator, it is necessary to increase the wind speed on the surface of the radiator or increase the radiation area, and as the type of the radiator, there are known types such as natural air cooling equipment, forced air cooling equipment, and water cooling equipment. A radiator and, if necessary, a heat exchanger can also be used. Among them, the heat sink is a typical example of a radiator because it can be manufactured at low cost by using extruded materials such as aluminum and copper, and can easily increase the radiating area. Depending on the place of use and application, it is a plate type, pin type, tower type Various heat sinks have been proposed.

(Electrically Insulating Bonding Material) The electrically insulating bonding material of the present invention needs to ensure insulation between a metal body and a heat sink and insulation between a plurality of electrodes electrically separated from the metal body. Further, a high thermal conductivity of 1 W / m · K or more is required in order to release heat generated in the photovoltaic element by the light collection to the radiator. Examples of such an electrically insulating bonding material include known metal oxides such as alumina (Al ₂ O ₃ ), AlN, Si ₃ N ₄ , and beryllia; and inorganic insulators such as glass, such as epoxy and phenol. Paper, polyimide,
Polyester, Teflon (registered trademark), or a different resin, or an organic insulating material represented by a combination of glass fiber and resin as a base material, for example, having a thermal conductivity of about 2000 W / m · K on both surfaces of the base material Diamond, 600W / m
-Boron nitride of K or more, SiC or BeO of about 240 to 450 W / mK, AlN of 100 to 200 W / mK,
30-100 W / m · K Si ₃ N ₄ , about 20 W / m · K
And a known heat-radiating adhesive or adhesive made of a silicone resin, an epoxy resin, an acrylic resin or the like impregnated with a powder such as alumina (Al ₂ O ₃ ).
In order to improve thermal conductivity, for example, diamond, boron nitride, SiC, BeO, AlN,
1 impregnated with Si ₃ N ₄ , alumina (Al ₂ O ₃ ) powder
A base material having a high thermal conductivity of up to several tens of W / m · K can also be used.

In the above-mentioned electric insulating bonding material, a base material and an adhesive (adhesive material) are separately provided, but as a unit having these functions integrated, it has a high thermal conductivity of 1 W / m · K or more. A double-sided adhesive insulating sheet may be used. For example, as having a film substrate, T404, T
414, No. 9 manufactured by Furukawa Electric Co., Ltd., No. 9 manufactured by Sumitomo 3M Co., Ltd.
Various known electrically insulating bonding materials such as known adhesive sheets such as 882 and No. 9885 can be used.

[0072]

The present invention will be described below in detail with reference to examples of the present invention. However, these examples are for illustrating the contents of the present invention, and the present invention is not limited to these examples.

(Example 1) FIG. 1 is a schematic diagram for explaining a mounting structure and a mounting method of a photovoltaic element according to Example 1 of the present invention. In FIG. 125
A photovoltaic device made of μm single crystal silicon,
A texture structure and an antireflection film (not shown) are formed on the sunlight receiving surface. Further, a pair of extraction electrodes (not shown) are provided on the non-light receiving surface of the photovoltaic element in the state shown in FIG. Au having a thickness of about 0.01 μm is vapor-deposited on the connected Al electrode having a thickness of 10 μm.

First, an oxygen-free copper sheet having a thickness of 0.7 mm is formed from a plurality of islands in which the electrode joining portion of the photovoltaic element and the external terminal attaching portion are integrated using known means such as press working. Forming a metal body 2 having a circuit pattern (FIG. 1)
(1)).

Thereafter, a cream solder 4 having a tin-lead eutectic composition (manufactured by Senju Metal Industry Co., Ltd.) is used as a bonding material between the metal body 2 and the photovoltaic element 1 at a position where the metal body is joined to the photovoltaic element 1. OZ63-381F4-9.5) having a thickness of 120 μm by a screen printing method using a known metal plate.
m (FIG. 1 (2)).

Further, a photovoltaic element 1 is arranged at a predetermined position of the metal body using a known chip mounter device (FIG. 1 (3)).

Further, the solder is melted and solidified by heating and cooling the above-described metal body using a known reflow apparatus under the temperature-dependent temperature change condition as shown in FIG. 3, and a photovoltaic element is formed on the metal body. Can be implemented.

Next, a radiator of 42 mm × 42 mm ×
At the center of a 10 mm pin type heat sink 5 (K4242-10B manufactured by Asuka Electronics Service Co., Ltd.), a double-sided adhesive insulating sheet 3 molded to 15 mm square as an electrically insulating bonding material.
(T404 manufactured by CHOMERICS) is attached (FIG. 1).
(4)).

Further, a metal body on which the photovoltaic element 1 is mounted is attached to a heat sink 5 by a double-sided adhesive insulating sheet 3.
It is placed on top and fixed by pressing with an air bag type press device as shown in FIG. This pressing device corresponds to the structure of the present invention having a portion that expands by gas injection.

Further, if necessary, a part of the metal body is cut using a known cutting device such as a diamond cutter as shown at a cutting position 20 in FIG. It can be used as an extraction electrode (FIG. 2 (6)).

(Embodiment 2) FIGS. 5 and 6 show Embodiment 2 of the present invention.
FIG. 2 is a schematic diagram illustrating a metal body on which the photovoltaic element is mounted and a mounting method according to the first embodiment, and shows a part of a continuous lead frame 6.

[0082] Width 100 mm, thickness 0.3 mm, length 10
Roll to to metal foil made of 42m alloy
A lead frame 6 is formed by continuously performing a press process by a Roll method, and forming a circuit pattern including a plurality of islands in which an electrode bonding portion of a photovoltaic element and an external terminal mounting portion are integrated (FIG. 5). (1)).

Further, the above-described continuous lead frame 6
At a position to be joined to the electrode of the photovoltaic element 1, a cream solder 4 having a tin-lead eutectic composition (OZ6 manufactured by Senju Metal Industry Co., Ltd.)
3-381F4-9.5) is applied by a dispenser (FIG. 5 (2)). The cream solder 4 is applied in a ball shape having a size of φ0.6 mm as viewed from above and arranged at a pitch of 1.5 mm.

Further, the above-described continuous lead frame 6
After the photovoltaic element 1 is arranged at a predetermined position using a known chip mounter device, the cream solder 4 is heated and cooled using a known reflow device under a temperature change condition as shown in FIG. After being melted and solidified, the photovoltaic element can be mounted on the lead frame (FIG. 6).
(3)).

FIG. 6D is a schematic view showing a state after the photovoltaic element 1 is mounted on the lead frame 4 by the above-described means. At the cutting position 21, a known means such as a diamond cutter is used. By cutting the lead frame 6 by using the method, the photovoltaic elements are individually mounted as in the first embodiment.

The photovoltaic element 1 in Example 2 is a single-crystal photovoltaic element having a thickness of 12 μm and a thickness of 125 μm as in Example 1, and has a texture structure and a reflection An prevention film is formed, and a pair of extraction electrodes is provided on the non-light receiving surface.

Although not shown in FIGS. 5 and 6, similar to the first embodiment, a radiator 42 mm × 42 mm × 10
mm heat sink (K manufactured by Asuka Denshi Service Co., Ltd.)
4242-10B), a double-sided adhesive insulating sheet (T40 manufactured by CHOMERICS Co., Ltd.)
4) is attached, and the metal body on which the photovoltaic element 1 is mounted is placed on the double-sided adhesive insulating sheet attached on the heat sink 5 and pressed and fixed by an air bag type press as shown in FIG.

Further, if necessary, a part of the metal body is cut by a known means such as a diamond cutter as shown at a cut position 20 in FIG.
The metal body can be taken out and used as an electrode.

According to such a configuration, when the photovoltaic element is mounted on a metal body, the metal body is continuously supplied as a lead frame. , And an existing lead frame mounting apparatus can be used.

(Embodiment 3) FIGS. 7 and 8 show Embodiment 3 of the present invention.
FIGS. 3A and 3B are schematic diagrams illustrating a mounting structure and a mounting method of the photovoltaic element according to the first embodiment.
This is a photovoltaic element made of arsenic gallium having a thickness of 200 μm, and a texture structure and an anti-reflection film are formed on the sunlight receiving surface. Further, a pair of extraction electrodes are provided on the non-light receiving surface of the photovoltaic element, and a thickness of 10 μm connected to the p-pole and the n-pole of the photovoltaic element, respectively.
About 0.01 μm thick Ni is deposited on the m Al electrodes.

First, similarly to the first embodiment, a 0.7 mm-thick circuit pattern having a plurality of islands in which the electrode junction of the photovoltaic element and the external terminal mounting portion are integrated.
Solder 4 having a tin-lead eutectic composition as a joining material (OZ63-381F4- manufactured by Senju Metal Industry Co., Ltd.)
9.5) is printed with a thickness of 120 μm by a screen printing method using a metal plate, and a photovoltaic element 1 is arranged at a predetermined position of the metal body, and then heated and cooled by a reflow device, so that a photovoltaic element is formed on the metal body. Mounting the power element (Fig. 7
(1) to (3)).

In this embodiment, a ceramic plate is used as a base material for joining the radiator and the metal body, and a silver paste is used as a base material joining material for joining the base material and the radiator. An adhesive having thermal conductivity was used as an electrically insulating bonding material for bonding the material and the metal body having the photovoltaic element mounted thereon.

A double-sided adhesive insulating sheet 3 (manufactured by Furukawa Electric Co., Ltd.) formed on the first surface of a ceramic plate made of alumina (Al ₂ O ₃ ) having a thickness of 0.32 mm and 15 mm □ as an electrically insulating joining material to a size of 15 mm □. EN500 / 50-2) and a silver paste having a thickness of 0.2 mm (ABLEBOND 84-1LM manufactured by Japan Ablestick Co., Ltd.) on the second surface.
I-T1) is uniformly applied, and a radiator 42 mm × 4
After being arranged at the center of a 2 mm × 10 mm pin type heat sink 5 (K4242-10B manufactured by Asuka Electronics Service Co., Ltd.),
The heat sink and the ceramic plate are fixed by heating in an oven at 125 ° C. for 2 hours. Further, the metal body on which the photovoltaic element 1 is mounted is placed on a double-sided adhesive insulating sheet attached to the first surface of the ceramic plate, and is pressed and fixed by an air bag type press as shown in FIG. (FIG. 7 (4), FIG. 8 (5), (6).

Further, if necessary, a part of the metal body is cut by a known cutting means such as a diamond cutter as shown at a cutting position 20 in FIG. Can be used as

In the mounting method described above, the bonding material is provided on both surfaces of the ceramic base material, and then the heating is performed to bond the second surface and the radiator. However, the bonding of the ceramic second surface and the radiator is performed. Thereafter, a bonding material may be attached to the first surface. A ceramic plate coated with a silver paste is disposed on the second surface at the center of the heat sink 5, and after heating and fixing, a double-sided adhesive insulating sheet is placed on the ceramic plate. Can be attached.

(Embodiment 4) FIGS. 9 and 10 are schematic views illustrating a metal body and a mounting method of a photovoltaic element according to Embodiment 4 of the present invention. A concentrating solar cell module using a receiver will be described.

The photovoltaic element 1 according to the fourth embodiment is a single-crystal photovoltaic element having a thickness of 12 μm and a thickness of 125 μm, as in the first embodiment. An prevention film is formed, and a pair of extraction electrodes is provided on the non-light receiving surface.

Width 50 mm, thickness 0.3 mm, length 100
Roll on a metal foil made of 0m copper-tungsten
Continuously press working by to Roll method, 20
A lead frame 6 is formed in which a circuit pattern having an electrode junction of a photovoltaic element is formed at a pitch of 0 mm, and a hole corresponding to a feed structure of a mounting device is formed at a longitudinal end.

Further, a cream solder 4 having a tin-lead eutectic composition as a bonding material (OZ63-381F4-9.5 manufactured by Senju Metal Industry Co., Ltd.) is provided at a position where the electrode of the photovoltaic element 1 of the continuous lead frame is bonded. Is applied with a dispenser. Cream solder 4 is φ0.6 when viewed from above
It is applied so as to be arranged at a pitch of 1.5 mm in a ball shape having a size of mm (FIG. 9A).

Further, after the photovoltaic element 1 is arranged at a predetermined position of the above-described continuous lead frame by using a known chip mounter device, and by using a known reflow device, FIG.
By heating and cooling under the temperature change conditions as shown in FIG. 9, the cream solder 4 is melted and solidified, and the photovoltaic element can be mounted on the lead frame (FIG. 9).
(2)).

After mounting the photovoltaic element on the lead frame by the above-described means, a pin-type heat sink of 42 mm × 42 mm × 10 mm at a 200 mm pitch so that a radiator is arranged on the opposing surface of the photovoltaic element of the lead frame. 5 (K4242-10B manufactured by Asuka Denshi Service Co., Ltd.), and a double-sided adhesive insulating sheet 3 (T40 manufactured by CHOMERICS Co., Ltd.) formed into a 15 mm square as an electrically insulating bonding material.
Paste in 4). Lead frame and heat sink 5
Is pressed and fixed by an air bag type press as shown in FIG. 3 (FIG. 9 (3)).

Further, the lead frame is cut at a predetermined cutting position 21 (FIG. 9 (3)) by using a known means such as a diamond cutter to obtain a lead frame as shown in FIG. 10 (4). As described above, the photovoltaic element and the heat sink were mounted on the metal body also serving as the extraction terminal at a pitch of 200 mm.

According to the above-described method, the metal body is cut so that five photovoltaic elements serially arranged on the metal body constitute one unit, thereby producing a concentrating solar cell receiver.

FIG. 10 (5) is a side view of FIG. 10 (4), and FIG. 10 (6) is a light collecting solar cell module 15 having the above-mentioned light collecting solar cell receiver provided with a Fresnel lens. FIG.

In the present embodiment, Roll to R
A photovoltaic element was mounted on a long metal body of 1000 m as in the case of the all system, and after mounting a heat sink, five photovoltaic elements were formed as one unit. For example, five photovoltaic elements are mounted. A method of batch-transporting such a 1500 mm long metal body, mounting five photovoltaic elements, and attaching a heat sink to create a concentrating solar cell receiver is also possible.

Embodiment 5 FIG. 11 is a schematic view showing a mounting structure of a photovoltaic element according to Embodiment 5 of the present invention.
A concentrating solar cell receiver structure and a concentrating solar cell module using the receiver will be described. FIG. 11A is a schematic top view showing a state in which a photovoltaic element is mounted on a metal body, and FIG. 11B is a collection diagram in which a radiator is mounted on the metal body on which the photovoltaic element is mounted. FIG. 11C is a schematic top view showing the mounting structure of the optical solar cell receiver, and FIG.
1 (2) is a schematic front view, FIG. 12 (4) is a schematic cross-sectional view taken along the line AA ′ of FIG. 11 (3), and FIG. 12 (5) includes the above-described concentrating solar cell receiver including a Fresnel lens and the like. It is a schematic diagram which shows the state arrange | positioned at the concentrating solar cell module.

The fifth embodiment differs from the fourth embodiment in that the structure of the radiator is changed. That is, the photovoltaic elements 1 are mounted on a metal foil made of copper-tungsten at a pitch of 200 mm, and five photovoltaic elements serially connected on a metal body constitute one unit. The metal body is cut at a pitch of 1000 mm.

An aluminum material was extruded on the second surface of the lead frame on which the photovoltaic element was mounted via a 15 mm × 880 mm double-sided adhesive insulating sheet (T404 manufactured by CHOMERICS Co., Ltd.) to form a 42 mm × 10 mm.
A fin-shaped heat sink having a cross section of 880 mm and having a length of 880 mm is bonded and fixed.

Further, the lead frame is cut at a predetermined cut position 21 using a known means such as a diamond cutter, for example, to cut the lead frame at a predetermined position, as shown in FIGS. 11 (2), (3) and 12 ( As described in 4), it is possible to provide a concentrating solar cell receiver in which five photovoltaic elements are arranged at a pitch of 200 mm and connected in series by a metal body also serving as an extraction electrode.

According to the above-described receiver structure of the concentrator photovoltaic cell, not only the metal body to be continuously supplied serves as an extraction electrode of the photovoltaic element but also the photovoltaic element can be connected in series by the metal body. It is. Furthermore, a heat sink continuously manufactured by extrusion molding is not only excellent in mass productivity, but also can be used as a support for the above concentrating solar cell receiver and module.

In this embodiment, Roll to Roll is used.
After mounting the photovoltaic element on a 1000 m long piece of metal as in the system, it was cut at a pitch of 1000 mm.
A metal body of 00 mm may be transported in a batch, and five photovoltaic elements may be mounted on the metal body.

In this embodiment, the photovoltaic element is mounted on the metal body and then bonded and fixed to the radiator. However, the metal body may be bonded and fixed to the radiator and then the photovoltaic element may be mounted.

Although the metal body is arranged in the radiator extrusion molding direction, the metal body may be cut out substantially at right angles to the extrusion molding direction and arranged so as to be substantially perpendicular to the extrusion molding direction.

In this embodiment, five photovoltaic elements are mounted on a metal body. However, any number of photovoltaic elements may be used as long as the number is two or more. Demonstrate.

[0115]

According to the present invention, a photovoltaic element having an electrode on a non-light-receiving surface, a photovoltaic element having an electrode on a non-light-receiving surface, and power generated by the photovoltaic element are transmitted to the photovoltaic element. In a mounting structure and a mounting method of a photovoltaic element including a metal body for taking out the photovoltaic element, the photovoltaic element is mounted on a first surface of the metal body, and a second surface By joining the electrically insulating joining material, the metal body becomes a heat spreader and can have a heat radiation function, and a large current can be easily taken out by the metal body.
In addition, the metal body can also serve as an external extraction electrode and a supporting material for the photovoltaic element, so that an expensive circuit board is not required.

Further, the radiator is joined to the second surface of the metal body via an electrically insulating joining material, whereby the heat radiation efficiency can be remarkably improved.

Further, by forming the metal body into a shape in which a plurality of photovoltaic elements can be mounted on the same frame, a roll-shaped metal body provided with a predetermined pattern on the metal body is continuously supplied. After the photovoltaic elements are continuously mounted on the body, they can be individually separated. That is, since the metal body has a shape capable of mounting a plurality of photovoltaic elements on the same frame, cutouts or holes are provided at the longitudinal ends of the metal body at intervals corresponding to the feed structure of the mounting device. As a result, continuous manufacturing is possible, the throughput is improved, the manufacturing cost can be reduced, and an existing mounting apparatus can be used.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating a mounting structure and a mounting method of a photovoltaic element according to a first embodiment.

FIG. 2 is a schematic diagram illustrating a mounting structure and a mounting method of the photovoltaic device according to the first embodiment.

FIG. 3 is a diagram showing an example of a temperature change condition over time during heating of solder.

FIG. 4 is a schematic diagram illustrating an air bag type press.

FIG. 5 is a schematic diagram illustrating a metal body and a method of mounting a photovoltaic element on the metal body according to Example 2.

FIG. 6 is a schematic diagram illustrating a metal body and a method of mounting a photovoltaic element on the metal body according to Example 2.

FIG. 7 is a schematic diagram illustrating a mounting structure and a mounting method of a photovoltaic element according to a third embodiment.

FIG. 8 is a schematic diagram illustrating a mounting structure and a mounting method of a photovoltaic element according to a third embodiment.

FIG. 9 is a schematic diagram illustrating a mounting structure and a mounting method of a photovoltaic element according to a fourth embodiment.

FIG. 10 shows a mounting structure of a photovoltaic device according to a fourth embodiment;
FIG. 4 is a schematic diagram illustrating a mounting method.

FIG. 11 shows a mounting structure of a photovoltaic device according to a fifth embodiment,
FIG. 4 is a schematic diagram illustrating a mounting method.

FIG. 12 is a mounting structure of a photovoltaic device according to a fifth embodiment;
FIG. 4 is a schematic diagram illustrating a mounting method.

FIG. 13 is a schematic diagram illustrating a conventional concentrating solar power generation system and a concentrating solar cell module.

FIG. 14 is a schematic diagram illustrating a conventional concentrating solar power generation system and a concentrating solar cell module.

FIG. 15 is a schematic diagram illustrating a photovoltaic element used in a concentrating solar cell module.

FIG. 16 is a schematic diagram illustrating a method for mounting a photovoltaic element used in a conventional concentrating solar cell module.

FIG. 17 is a schematic view illustrating a method for mounting a photovoltaic element used in a conventional concentrating solar cell module.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 photovoltaic element 2 metal body 3 electrically insulating bonding material 4 bonding material 5 radiator 6 lead frame 7 base material 8 base material bonding material 9 hole 10 Fresnel lens 11, 12 terminal 15 solar cell module 100 photovoltaic element 101 Circuit board 102 Silver paste 103 Heat sink 104 Circuit pattern 105 Solder 106 Extraction electrode 108 Lead wire 109 Tracking device 110 Fresnel lens 115 Solar cell module

Claims (15)

[Claims] 1. A photovoltaic device comprising: a photovoltaic device having an electrode on a non-light receiving surface; and a metal body for extracting power generated by the photovoltaic device to outside the photovoltaic device. In the mounting structure, the photovoltaic element is bonded to a first surface of the metal body, and an electrically insulating bonding material is bonded to a second surface. 2. The method according to claim 1, wherein the metal body is at least gold, silver, copper,
The mounting structure for a photovoltaic element according to claim 1, wherein any one of aluminum, nickel, iron, cobalt, and tungsten, or an alloy thereof is a main component. 3. The method according to claim 1, wherein the metal body has a thickness of 0.05 to 2 mm.
The mounting structure of a photovoltaic element according to claim 1, wherein the mounting structure has a plate shape. 4. The photovoltaic device according to claim 1, wherein the metal body has a shape capable of mounting a plurality of photovoltaic devices on the same frame. Mounting structure. 5. The electrical connection between the photovoltaic element and the metal body is made by a bonding material containing at least one of tin, lead, silver, and copper.
5. A mounting structure of the photovoltaic element according to any one of Items 4 to 4. 6. The electric insulating bonding material according to claim 1, wherein the adhesive material has a heat conductive adhesive.
The mounting structure of the photovoltaic element according to any one of the above. 7. The mounting of the photovoltaic device according to claim 1, wherein the electrically insulating bonding material is a double-sided adhesive insulating sheet having thermal conductivity. Construction. 8. The radiator according to claim 1, wherein the second surface of the metal body is joined to a radiator via an electrically insulating joining material.
8. The mounting structure of the photovoltaic element according to any one of items 1 to 7. 9. The radiator according to claim 8, wherein said radiator has at least one flat surface.
3. The mounting structure of the photovoltaic element according to 1. 10. The method for mounting a photovoltaic device according to claim 8, wherein the radiator has a long shape on which at least two photovoltaic devices can be mounted. 11. A photovoltaic device having an electrode on a non-light-receiving surface, a metal body for extracting power generated by the photovoltaic device out of the photovoltaic device, and heat generated by light reception. In a mounting method of a photovoltaic element including a radiator for radiating heat, at a predetermined position on the first surface of the metal body,
An element joining step of joining the photovoltaic elements with a joining material, and a radiator joining step of joining a radiator with an electrically insulating joining material at a predetermined position on the second surface of the metal body. Characteristic mounting method of photovoltaic element. 12. The method for mounting a photovoltaic element according to claim 11, wherein the radiator bonding step is performed after the element bonding step, and the first bonding of the metal body is performed in the element bonding step. A step of arranging a bonding material at a predetermined position on a surface; a step of arranging the photovoltaic element at a predetermined position where the bonding material on the metal body is arranged; and heating the metal body by the bonding material. And bonding the photovoltaic element to the radiator. In the radiator bonding step, a step of disposing an electrically insulating bonding material at a predetermined position on the radiator; On the electrically insulating bonding material provided at a predetermined position, a step of arranging the metal body to which the photovoltaic element is bonded in a state where the second surface side is bonded, and pressing from the upper surface of the photovoltaic element. Joining the metal body and the radiator And a step of mounting the photovoltaic element. 13. The element joining step, wherein the metal body is a lead frame, and in the element joining step, the lead frame is continuously supplied, and the photovoltaic elements are joined to the lead frame at equal intervals. The method for mounting a photovoltaic element according to claim 12, further comprising a step of individually separating the lead frames after the step. 14. The pressing means used for pressing in the radiator joining step is a structure having a portion that expands by injecting gas, and the pressing is performed by the expanding portion. Or a mounting method of the photovoltaic element according to 13. 15. The method for mounting a photovoltaic element according to claim 11, wherein the element bonding step is performed after the radiator bonding step. Bonding the radiator on the two surfaces via the electrically insulating bonding material, wherein in the element bonding step, arranging a bonding material at a predetermined position on the first surface of the metal body And a step of disposing the photovoltaic element at a predetermined position where a bonding material on the metal body is disposed, and a step of bonding the metal body and the photovoltaic element by the bonding material by heating, A method for mounting a photovoltaic element, comprising at least: