JP2001230439A - Method of manufacturing ball diode substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To previously form a ball cell substrate, to remove the diffusion layer of second conductivity tape silicon along a spherical outline without local heating, to expose first conductivity type silicon and to form a ball diode substrate. SOLUTION: A first process for preparing a ball cell having a spherical substrate constituting first conductivity type silicon and second conductivity type silicon made to form p-n junction on the surface, a second process for arraying plural ball cells in a matrix shape, exposing a part of or whole hemispheres of second conductivity type silicon in the ball cells by sealing resin, and forming a ball cell substrate where the ball cells are mutually connected; and a third process for spraying abrasive grains to the exposed second conductive silicon of the ball cell substrate with prescribed jet pressure by a sand blasting method, removing the exposed part of second conductivity type silicon and exposing first conductivity type silicon; are given.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a ball diode substrate having a configuration in which a plurality of ball diodes as components of a solar module (solar cell module) are mutually connected in a matrix.

[0002]

2. Description of the Related Art Heretofore, a photovoltaic portion has been provided by including a planar p-type silicon substrate as an example and n-type silicon formed on the surface of the substrate to form a pn junction. A flat photodiode has internal electrolysis, and when it is exposed to sunlight, electron-hole pairs are generated. These generated electrons and holes are separated by an internal electric field, Is collected on the n side, and holes are collected on the p side. When a load is connected to the outside, a current flows from the p side to the n side. Utilizing this effect, practical use of a planar solar cell module in which a number of elements (photodiodes) for converting light energy into electric energy are connected in series / parallel is being promoted.

Further, in recent years, by melting silicon semiconductor particles in a floating state such as weightlessness or magnetic levitation and allowing them to fall naturally, a spherical substrate (Ball Semiconductor) of p-type or n-type silicon such as monocrystalline silicon or polycrystalline silicon is obtained.
A technique for forming a p-type or p-type n-type silicon spherical substrate is subjected to a process such as vapor phase growth, vapor phase diffusion, oxide film formation, and electrode formation to form a photo diode (ball diode). When configured, it is used because it functions as an excellent spherical light-receiving optical element that can receive light such as sunlight that enters from each direction.

For example, a ball cell including n-type silicon formed to form a pn junction is formed on the surface of the spherical substrate of p-type silicon, and the ball cell is formed by an etching method or a grinding method. Practical use of a ball diode in which a part or all of the hemispherical portion of n-type silicon of a ball cell is removed to expose a p-type silicon substrate has been promoted. Since the ball diode can receive light such as sunlight from any direction and has a larger surface area than a conventional planar type surface area, the ball diode is suitable for forming a solar cell module. , N
Providing a common electrode on the silicon mold allows individual ball diodes to be connected in series and parallel, and the structure of the solar cell module can be simplified.

[0005] Japanese Patent Application Laid-Open No.
As shown in No. 13633, a first aluminum foil is prepared, an opening is formed in a predetermined position of the first aluminum foil, a skin portion is silicon of a second conductivity type, and a portion below the skin portion is a first conductivity type. Silicon spherical semiconductor particles are applied to each of the openings,
After the semiconductor particles are arranged so as to protrude from both sides of the first aluminum foil and make ohmic contact, the second conductive type silicon skin portion on one side of the first aluminum foil is etched, polished or the like. A configuration of a solar cell module in which semiconductor particles (solar diodes) that have been removed to expose the first conductivity type silicon are arranged in a metal foil matrix is disclosed.

[0006]

However, in the above configuration, a common electrode is formed in advance on a plurality of the solar diodes, an electrical connection form is fixed, and the solar diodes are individually connected. Solar modules (solar cell modules), which are connected in series and parallel by combining the required number of solar diodes, which are the minimum units of the components that make up a solar module (solar cell module), There is a problem that the degree of freedom in designing a solar cell array (solar cell array) or the like in which the solar modules are connected in series and parallel as needed is hindered.

Further, since a surface grinding method or an etching method is used as a means for removing the second conductive type silicon skin portion and exposing the first conductive type silicon under the skin portion,
It had the following problems to be solved.

When a surface grinding method is used to remove a part of the silicon of the second conductivity type and expose the silicon of the first conductivity type along the spherical contour, a part of the silicon of the second conductivity type is formed along the spherical shape. Grinding and removing the contours has drawbacks in terms of workability and productivity. Therefore, a part of the spherical surface is ground into a flat surface to form a bottom flat, thereby forming one of the second conductive type silicon. A method of removing the portion and exposing the first conductivity type silicon is adopted. However, when the bottom flat is formed by performing the grinding process, the bottom heat is locally heated by the grinding heat, and the thermal stress causes microcracks (crystal defects) in the first conductivity type silicon and the second conductivity type silicon. This causes a problem that the performance of the ball diode is adversely affected.

Furthermore, since silicon of the first conductivity type and silicon of the second conductivity type coexist on the same flat surface of the bottom flat, it is difficult to take out independent electrodes.

When the etching method is used to remove the spherical second conductive type silicon, a part of the second conductive type silicon can be easily removed along the spherical shape. Expensive equipment is required for pattern formation and the like, and there is a problem that there is a problem in workability and productivity such as etching depth and liquid management thereof, and there is a concern that pollutants may be discharged to the environment.

The present invention has been made in view of the above circumstances, and a first object is to provide a solar module (solar module) formed by connecting a single or required number of ball diodes in series and parallel. (Battery module) and the like.

A second object is to provide a spherical ball.
An object of the present invention is to improve the workability and productivity without easily handling cells and without using expensive equipment.

A third object is to remove the second conductivity type silicon along the spherical contour without exposing the first conductivity type silicon without local heating.

Yet another object is to eliminate the need for complicated controls and to eliminate the generation of environmental pollutants.

[0015]

According to a first aspect of the present invention, there is provided a method of manufacturing a ball diode substrate, comprising the steps of: providing a plurality of ball diodes as a minimum unit of a component of a solar module (solar cell module); A method for manufacturing a ball diode substrate formed by arranging the ball diodes in a matrix and interconnecting the ball diodes with a sealing resin, wherein at least a surface of the ball diode constitutes first conductivity type silicon; A first step of preparing a ball cell having a second conductivity type silicon formed so as to form a pn junction on the surface; and arranging a plurality of the ball cells in a matrix, and using a sealing resin. By the said ball
A second step of exposing a portion or all of the second conductivity type hemisphere of each cell of the cell and forming a ball cell substrate interconnecting the ball cells; and exposing the ball cell substrate. A third step of exposing the first conductive type silicon by removing the exposed portion of the second conductive type silicon by spraying abrasive grains at a predetermined ejection pressure to the second conductive type silicon by sandblasting. By sequentially performing the above-described steps, a ball that forms a photovoltaic portion made of the first conductivity type silicon and the second conductivity type silicon formed to form a pn junction with the first conductivity type silicon is formed. It is configured to form a ball diode substrate in which a large number of diodes are mutually fixed in a matrix by a sealing resin.

According to a second aspect of the present invention, in the method of manufacturing a ball diode substrate according to the first aspect, the ball cell is a p-type or n-type single crystal or polycrystalline silicon. And a spherical substrate of
The structure is made of n-type or p-type single crystal or polycrystalline silicon formed to form a pn junction. The spherical body of the first conductivity type silicon is p-type or n-type single crystal or polycrystalline silicon, and the second conductivity type silicon formed to form a pn junction on the surface thereof is:
It is characterized by being n-type or p-type single crystal or polycrystalline silicon.

According to a third aspect of the present invention, there is provided a method of manufacturing a ball diode substrate, wherein the ball cell comprises a spherical glass or metal substrate and a surface thereof. P or n deposited on
The structure is made of amorphous silicon and n-type or p-type amorphous silicon formed so as to form a pin junction.

A ball diode manufacturing method according to a fourth aspect of the present invention is the ball diode manufacturing method according to any one of the first to third aspects, wherein the ball cell substrate includes an upper die and a predetermined die. Are arranged in a matrix at a pitch of
The ball cell is placed in the concave portion of the cavity block using a resin mold having a concave portion provided with a suction port and a lower mold having a detachable cavity block. A configuration formed by injecting a sealing resin in a state in which a part or all of the hemisphere is adsorbed to the concave portion and interconnecting in a state in which a part or all of the surface of the hemisphere of the ball cell is exposed. Have been.

According to a fifth aspect of the present invention, there is provided a ball diode manufacturing method according to any one of the first to fourth aspects, wherein the sealing resin is a thermosetting or thermoplastic resin. It is configured to use one type selected from transparent resins.

According to a sixth aspect of the present invention, in the method of manufacturing a ball diode according to any one of the first to fifth aspects, the step of exposing the silicon of the first conductivity type includes a step of: A sand blasting apparatus is provided with a predetermined means including an exposing means comprising abrasive grain ejection nozzles arranged in a staggered manner at intervals, a cleaning means comprising a cleaning liquid discharge nozzle, and a transport means for causing a ball / cell substrate to travel at a predetermined speed. While the ball cell substrate is running at a transport speed, the exposed diffusion layer of the second conductivity type silicon is removed.

According to a seventh aspect of the present invention, there is provided a method of manufacturing a ball diode substrate according to any one of the first to sixth aspects, wherein the abrasive grains have a particle size of 5 μm to 5 μm. It is configured to use one selected from silica sand of about 200 μm, garnet, glass beads, sintered aluminum, silicon carbide, boron carbide, and diamond.

The method of manufacturing a ball diode according to claim 8 is the method of manufacturing a ball diode according to any one of claims 1 to 7, wherein the jet pressure of the abrasive grains is:
The abrasive particles are sprayed in a range of about 0.1 MPa to 0.7 MPa.

According to the first to eighth aspects of the present invention, a ball cell substrate is formed in which ball cells are interconnected in a matrix with a sealing resin in advance.
The positional accuracy between cells is stable, and high-density arrangement is possible. In addition, the handling of the next step operation such as sandblasting is facilitated and the workability is improved, and the sealing resin can perform a protection function of preventing the damage of the surface of the diffusion layer of the second conductivity type silicon, thereby improving reliability. Can be improved.

Since a ball diode substrate in which the second conductivity type silicon is removed from the ball cell substrate and the first conductivity type silicon is exposed is formed by the sandblast method, no local heat is generated. And the second
Conductive silicon can be removed at a time, and a high-quality ball diode substrate can be formed.

Further, since the ball diode substrate is formed, the ball diodes are separated by dicing into individual or row or column connecting a plurality of ball diodes, and then electrode pads are formed on required portions. This makes it possible to combine the ball diode substrates with one another in various ways, thereby improving the degree of freedom in designing a required solar module or the like.

In particular, according to the constitutions of claims 6 to 8,
Since the second conductive type silicon of the ball cell substrate is mechanically scraped off by sand blasting, the second conductive type silicon can be easily processed at room temperature without local heat generation, and the heat distortion region along the exposed portion can be easily obtained. No microcracks due to thermal distortion are generated compared to conventional grinding and laser exposure technologies, and high-quality ball diodes can be formed, improving the stability of solar modules (solar cell modules). No adverse effects.

Further, since the area to be shaved by the spread of the abrasive grains is large, the workability of the exposure is improved and
The transfer, sandblasting, and cleaning of the cell substrate can be performed at the same time, so that the production can be automated and the productivity can be improved, and the control of the transfer speed and the ejection pressure can be simplified, and the equipment cost can be reduced.

Further, since the saddle blast method is used to remove the diffusion layer of the second conductive type silicon, abrasive grains can be collected, and expensive equipment that requires complicated control compared to the conventional etching method is required. It is not necessary, generates less environmental pollutants, improves workability and productivity, and can reduce manufacturing costs.

[0029]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a ball diode substrate manufacturing method according to an embodiment of the present invention;

FIG. 1 is a plan view showing a ball diode substrate according to an embodiment of the present invention in which a large number of ball diodes are arranged in a matrix, FIG.
FIG. 3A is a sectional view showing a spherical substrate according to an example of the embodiment of the present invention, and FIG. 3B is a sectional view showing a ball diode according to an example of the embodiment of the present invention.

First, a ball, which is an embodiment of the present invention, will be described.
As shown in FIGS. 1 and 2, the diode substrate 200 is a spherical substrate of p-type polycrystalline silicon, which is an example of the spherical substrate 10 of the first conductivity type silicon having a diameter of 1 mm (FIG. 3A).
Pn) on the entire surface of the p-type polycrystalline silicon 10.
A photovoltaic portion 13 made of n-type polycrystalline silicon which is an example of the second conductivity type silicon 12 formed by diffusing impurities shallowly from the surface at a high temperature to form a bond 11; A large number of ball diodes 15 (see FIG. 3B) each having an exposed portion 14 in which a part or the entire hemisphere of the p-type polycrystalline silicon 10 is exposed are arranged in a matrix. The sealing resin portion 16 is formed by an acrylic resin (see FIGS. 7 and 9), which is an example of the transparent sealing resin 25, which is joined to each other while the exposed portion 14 is exposed. Here, the spherical body 10 of the first conductivity type silicon is formed by depositing p (n) -type amorphous silicon on a spherical substrate of n-type silicon, a spherical glass or a metal substrate in addition to a spherical substrate of p-type silicon. You can also. In addition, ball
The diode 15 is a semiconductor having two electrodes.

Next, an example of a method of manufacturing the ball diode substrate will be described with reference to the accompanying drawings. The manufacturing process of the ball diode substrate includes a first process of forming a ball cell from P-type silicon grains, and a second process of forming a ball cell substrate in which the ball cells are arranged in a matrix. A third step of removing the respective n-type silicon diffusion layers from the ball cell substrate and exposing the P-type silicon. Hereinafter, each step will be described.

First, a first step of forming a ball cell will be described with reference to the accompanying drawings. FIG.
FIG. 5 is a cross-sectional view showing a configuration of a ball cell according to an example of the embodiment of the present invention. FIG. 5 is a diagram in which a number of ball cells according to an example of the embodiment of the present invention are arranged in a matrix and fixed to each other. FIG. 6 is a cross-sectional view of the same ball / cell substrate.

In the first step, for example, a p-type polycrystalline silicon particle having a diameter of 1 mm, which is an example of a semiconductor silicon particle, not shown, is melted in a gravity-free state or a floating state such as magnetic levitation and dropped naturally. Thus, a spherical substrate of p-type polycrystalline silicon (see FIG. 3A), which is an example of the spherical substrate 10 of the first conductivity type silicon, which is cooled while being dropped in a vacuum while being cooled, is formed. At the same time, the p-type polycrystalline silicon
P (phosphorus) on the spherical substrate 10 of silicon mold, POCl
3. The second conductivity type silicon formed to form a pn junction 11 on the entire surface by heating and diffusing in a gas atmosphere at a temperature of about 850 to 950 ° C. using P2O5 or the like as a diffusion source. Photovoltaic unit 13 comprising a diffusion layer of n-type polycrystalline silicon, which is an example of spherical substrate 12 of FIG.
A ball cell 10a is formed as shown in FIG.

Here, the diameter of the p-type polycrystalline silicon grain is set to 1
However, p-type polycrystalline silicon particles having a diameter in the range of 0.25 mm to 10 mm (preferably, 1 mm to 2 mm) may be used. If it is less than 0.25 mm, it is difficult to handle such as forming an electrode, and if it is 10 mm or more, it is necessary to form an electrode pattern composed of a current collecting finger and a bus bar, and the light condensing area is reduced and the number of work steps is increased.

Further, the diffusion layer of the n-type silicon 12 has a free electron density of about 2 to 4 * 1020 cm-3.
Further, it is preferable that the pn junction is formed at a position having a depth of about 0.6 μm.

Further, the impurity density near the surface is 1021
Since it becomes about cm −3 (dead layer), plasma etching is performed if necessary, and the dead layer is removed to increase the surface resistance.
A tin oxide (TiN) film may be formed for compensation. Thereby, the conversion efficiency can be improved.

In the case of a spherical substrate of n-type silicon, B (boron) is diffused using BCl3, BBr3 or the like as a diffusion source, so that a ball cell having a p-type silicon diffusion layer on its surface is provided. Is formed.

Further, the n-type or p-type diffusion layer can be formed by a solid phase diffusion method or an ion implantation method other than the gas diffusion method.

In addition to the p-type or n-type polycrystalline silicon grains, p-type or n-type single-crystal silicon grains can be used.

Next, a second step of forming the ball cell substrate 100 will be described with reference to FIGS. FIG. 7 is a cross-sectional view showing an outline of a resin-sealed state using a resin-sealing mold according to an example of the embodiment of the present invention. FIG. 8 is mounted on a cavity block according to an example of the embodiment of the present invention. FIG. 9 is a cross-sectional view showing an outline of a resin-sealed state using an alignment jig according to an example of the embodiment of the present invention.

In the second step, first, the ball cell 10a formed in the first step is replaced with an upper mold 17, an example of a resin mold, a lower mold 18, and a plurality of ball cells. Suction port 19a for sucking and fixing 10a at a predetermined mounting pitch
FIG. 7 is provided with a cavity block 20 which is provided with concave portions 19 having a matrix shape and is detachable.
Using a resin sealing mold 21 shown in FIG. 8, the cavity block 20 is aligned with an alignment jig 22 having suction means (FIG. 9).
), And the ball cells 10a are mounted on the respective concave portions 19 in a state of being sucked by the vacuum 23, thereby removing excess ball cells 10a.

Next, as shown in FIG. 8, the cavity block 20 on which the ball cells 10a are mounted is mounted on the resin mold 21 and the vacuum 23 is used.
A liquid acrylic resin, which is an example of a liquid sealing resin 25, is injected into the cavity block 20 in a state where the ball cells 10a are collectively adsorbed and fixed in the concave portions 19, and a part of the hemispheric surface of the ball cells 10a is formed. Alternatively, a sealing resin portion 16 that exposes all of them is formed to mutually fix the ball cells 10a, and the plurality of ball cells 10a are arranged in a matrix. Then, a part or all of the hemispherical surface of the diffusion layer of the n-type silicon 12 is exposed from the surface of the sealing resin portion 16 as shown in FIGS.
Is formed (second step).

Here, the ball cell substrate 100 is formed by a casting method (casting method, potting method, dropping method) as shown in FIG. 9 in addition to the transfer molding method using the resin sealing mold. Squeezing method), it is also possible to interconnect the ball cells by heating and hardening after injecting the liquid resin 25 to form the sealing resin portion 16 and to reduce equipment costs. Can be planned.

In addition, the liquid sealing resin agent 25 can form the sealing resin portion 16 using a thermosetting or thermoplastic transparent resin such as glass or silicon resin in addition to the liquid acrylic resin.

Next, referring to FIG. 10 and FIG.
A third step of removing the diffusion layer of n-type silicon, which is an example of conductive silicon, and forming a ball diode substrate exposing p-type silicon, which is an example of the first conductive silicon, will be described. FIG. 10 is a schematic diagram showing a step of forming a ball diode substrate using a sandblast method according to an example of the embodiment of the present invention, and FIG. 11 is a diffusion layer of the second conductivity type silicon according to an example of the embodiment of the present invention. FIG. 6 is a cross-sectional view showing a schematic view illustrating a state in which the is removed.

In the third step, the ball / cell substrate 100 is fixed on a carrier plate (not shown) and exposed on the surface of the ball / cell substrate 100 while running in a conventional sandblasting apparatus. As shown in FIG. 10, on the surface of the diffusion layer of the n-type silicon 12, the injection nozzles 27 of a predetermined injection range 26 are arranged in a staggered manner at predetermined intervals, and a predetermined ejection pressure ( 0.1MP
(preferably 0.6 MPa in the range of a to 0.7 MPa) and a particle size of 5 μm to 200 μm selected from silica sand, garnet, glass beads, sintered aluminum, silicon carbide, boron carbide, diamond, and the like (preferably firing). (Aluminum) Exposed portion 1 of diffusion layer of n-type silicon 12 by spraying abrasive grains
4a, the p-type silicon 10 is subjected to an exposing process, and a cleaning process is performed to remove a residue such as the abrasive grains, and a plurality of ball diodes 15 are arranged in a matrix.
FIGS. 1 and 2 (a state in which all the hemispheres are exposed), 3 (b) (a part of the hemisphere), in which a part or all of the hemisphere of the p-type silicon 10 is exposed on the surface of the sealing resin 16. The ball diode substrate 200 is formed as shown in FIG.

Here, it is preferable that the injection angle is about 60 ° with respect to the substrate surface. Further, a regulating plate may be provided so as to eject abrasive grains coming off the substrate into the projection range.

The present invention may be embodied in many different forms without departing from its spirit or essential characteristics. Therefore, the above-described embodiment is merely an example in every aspect, and should not be interpreted in a limited manner. The scope of the present invention is defined by the scope of the claims, and is not restricted by the specification text. Furthermore, all modifications and changes belonging to the equivalent scope of the claims are within the scope of the present invention.

For example, if necessary, after the ball cell substrate 100 is formed in advance, the ball cell substrate 10
An aluminum foil having an opening smaller than the exposed portion at a position corresponding to the diffusion layer of the second conductivity type silicon 12 on the diffusion layer of the second conductivity type silicon 12 exposed on the surface A configuration may be provided in which a step of forming a current collecting electrode pattern in ohmic contact with the diffusion layer of the second conductivity type silicon 12 is provided. As a result, a good current collecting electrode pattern can be formed since the positional accuracy between the ball and the cell is stable.

Further, after the cleaning, a step of forming an interlayer insulating layer between the electrode layer and the diffusion layer in the exposed portion of the p-type silicon 10 exposed on the surface of the formed ball diode substrate 200 is provided. You can also.

Further, an elastic resin coating film 24 may be provided in the concave portion provided in the cavity block in which the ball cells are arranged and mounted. Thereby, the adhesion between the ball cell 10a and the concave portion is further improved.

Furthermore, it is also possible to form the sealing resin portion 16 by using a liquid photoresist and photo-curing. With this, it is also possible to adopt a configuration in which a step of re-fixing with a transparent resin is provided after a treatment such as formation of an electrode is completed.

Further, since the ball diode substrate in which a plurality of ball diodes are connected is formed, it is possible to easily form the apex electrode and the low point electrode in the state of the ball diode substrate.

[0055]

According to the ball diode manufacturing method of the present invention, since the ball cell substrate is formed in advance, it is easy to handle the spherical ball cells and a high-density arrangement is possible. Thus, workability and productivity can be significantly improved.

Further, since the sand blast method is used to remove a part of the spherical second conductive type semiconductor layer,
The diffusion layer of the second conductivity type silicon can be easily removed along the spherical contour without requiring expensive equipment and without local heat generation. As a result, high quality balls
A diode substrate can be formed.

Further, since the ball diodes are arranged on the sealing resin substrate, the processing operation in the next step is facilitated, and the productivity is improved. For example, the ball diode substrate may be diced in columns or rows to form a strip-shaped substrate in which a plurality of ball diodes having electrodes formed at predetermined locations are connected. Thus, a solar module or the like can be formed by alternately arranging p-type or n-type strip-shaped substrates in which the diffusion layers are arranged.

Further, individual ball diode substrates can be formed by dicing the strip-shaped substrate. As a result, the present invention can be applied as a battery for driving an integrated circuit chip such as a photovoltaic power generator or a logic or a memory, and the degree of freedom in design such as application to a PC card, an IC tag, and the like can be improved.

[Brief description of the drawings]

FIG. 1 is a plan view showing a ball diode substrate according to an embodiment of the present invention, in which a large number of ball diodes are arranged in a matrix.

FIG. 2 is a sectional view of the same.

FIG. 3A is a cross-sectional view illustrating a spherical base according to an example of the embodiment of the present invention, and FIG. 3B is a cross-sectional view illustrating a ball diode according to an example of the embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a configuration of a ball cell according to an example of an embodiment of the present invention.

FIG. 5 is a plan view showing a ball cell substrate according to an embodiment of the present invention, in which a large number of ball cells are arranged in a matrix.

FIG. 6 is a sectional view of the same.

FIG. 7 is a cross-sectional view showing an outline of a resin-sealed state using a resin-sealing mold according to an example of an embodiment of the present invention.

FIG. 8 is a cross-sectional view showing a state of being mounted on a cavity block according to an example of an embodiment of the present invention.

FIG. 9 is a cross-sectional view illustrating an outline of a resin-sealed state using an alignment jig according to an example of an embodiment of the present invention.

FIG. 10 is a schematic view showing a step of forming a ball diode substrate using a sandblast method according to an example of an embodiment of the present invention.

FIG. 11 is a cross-sectional view showing a schematic view illustrating a state where a diffusion layer of the second conductivity type silicon is removed according to an example of an embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 ball cell substrate 200 ball diode substrate 10 first conductive type spherical silicon substrate 10 a ball cell 11 pn bond 12 second conductive type silicon 13 photovoltaic unit 14 exposed part 15 ball diode 16 sealing resin part 17 Upper die 18 Lower die 19 Concave part 19a Suction port suction through hole 20 Cavity block 21 Resin sealing mold 22 Alignment jig 23 Vacuum 24 Elastic resin coating film 25 Liquid sealing resin material 26 Injection range 27 Injection nozzle 28 Cleaning shower Range 29 shower nozzle

Continued on the front page F term (reference) 5F049 MA02 MA04 MB03 MB05 NA18 QA01 QA11 RA10 SE09 SE11 SS01 SS06 5F051 AA02 AA05 BA14 DA01 DA03 DA04 DA20 FA16 FA17 FA19 GA01 GA11 GA20

Claims (8)

[Claims] 1. A ball formed by arranging a large number of ball diodes as a minimum unit of a solar module (solar cell module) in a matrix and interconnecting the ball diodes with a sealing resin. -A method for manufacturing a diode substrate, wherein at least the surface is the first
A spherical substrate constituting conductive silicon, and pn
A first step of preparing a ball cell comprising silicon of the second conductivity type formed to form a junction; arranging a plurality of said ball cells in a matrix; A second step of exposing a portion or all of a hemisphere of the second conductivity type silicon of each of the cells and forming a ball cell substrate interconnecting the ball cells; and A third step of spraying abrasive grains to the exposed second conductivity type silicon with a predetermined ejection pressure by sandblasting to remove the exposed portion of the second conductivity type silicon and expose the first conductivity type silicon. Then, by sequentially performing the above steps, the first conductive type silicon and the second conductive type silicon formed to form a pn junction with the first conductive type silicon are formed. Ball diode manufacturing method of a substrate, which comprises forming a ball diode substrate are mutually fixed ball diode by a large number matrix in a sealing resin constituting the electromotive force unit. 2. The method of manufacturing a ball diode substrate according to claim 1, wherein the ball cell is a p-type or n-type ball cell.
A ball comprising a spherical substrate of type single crystal or polycrystalline silicon and an n-type or p-type single crystal or polycrystalline silicon formed on its surface to form a pn junction.・ Method of manufacturing diode substrate. 3. The method of manufacturing a ball diode substrate according to claim 1, wherein said ball cell comprises a spherical glass substrate or a metal substrate, and p-type or n-type amorphous silicon deposited on the surface thereof. And n-type or p-type amorphous silicon formed to form a pin junction. 4. The method for manufacturing a ball diode substrate according to claim 1, wherein
The cell substrate is a resin mold having an upper mold and a lower mold having a concave portion provided with a suction port and arranged in a matrix at a predetermined pitch and having a detachable cavity block. And placing the ball cell in the concave portion of the cavity block, injecting a sealing resin in a state where a part or all of the hemisphere is adsorbed in the concave portion, and forming a part of the hemisphere of the ball cell. Alternatively, a method for manufacturing a ball diode substrate, characterized in that all the surfaces are exposed and mutually connected. 5. The method of manufacturing a ball diode according to claim 1, wherein the sealing resin comprises:
A method for manufacturing a ball / diode substrate, comprising a structure using one selected from thermosetting or thermoplastic transparent resins. 6. The method of manufacturing a ball diode substrate according to claim 1, wherein the step of exposing the first conductivity type silicon includes the step of forming abrasive grains arranged in a staggered manner at predetermined intervals. The ball / cell substrate travels at a predetermined transport speed in a sandblasting apparatus including an exposure unit including a jet nozzle, a cleaning unit including a cleaning liquid discharge nozzle, and a transport unit configured to transport the ball / cell substrate at a predetermined speed. A method of removing the exposed diffusion layer of the second conductivity type silicon while removing the silicon. 7. The method for manufacturing a ball diode substrate according to claim 1, wherein the abrasive grains are:
Silica sand, garnet, whose particle size is 5 μm to 200 μm,
A method for manufacturing a ball / diode substrate, comprising a kind selected from glass beads, sintered aluminum, silicon carbide, boron carbide, and diamond. 8. The method for manufacturing a ball diode substrate according to claim 1, wherein a jet pressure of said abrasive grains is in a range of 0.1 MPa to 0.7 MPa. Manufacturing method of ball diode substrate.