JP2011243970A - Photoelectric conversion device and manufacturing method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photoelectric conversion device having defects suppressed as much as possible by selectively filling a structure defect such as a pin hole or a crack of a semiconductor film with an insulation resin, and a manufacturing method of the photoelectric conversion device.SOLUTION: A manufacturing method of a photoelectric conversion device comprises forming on a substrate, a first electrode, a first impurity semiconductor layer, an intrinsic semiconductor layer, and a second impurity semiconductor layer; specifying the position of a structure defect in the semiconductor layer or in a part thereof by using means for detecting the structure defect; discharging a liquid insulation resin material to the structure defect or the periphery thereof by using means for discharging a liquid, filling the inside of the structure defect with the insulation resin material; curing the insulation resin material by using means for curing the insulation resin material, and forming a second electrode on the second impurity semiconductor layer and the cured insulation resin.

Description

The present invention relates to a photoelectric conversion device and a manufacturing method thereof.

In recent years, photoelectric conversion devices, which are power generation means that do not emit carbon dioxide during power generation, have attracted attention as a measure against global warming. As a typical example, solar cells for power supply such as residential use are known, and crystalline silicon solar cells such as single crystal silicon and polycrystalline silicon are mainly used. The solar cell can efficiently generate power when irradiated with light of high illuminance such as sunlight, but has a characteristic that the power generation capacity is extremely reduced in cloudy or rainy weather or under indoor fluorescent lamps. is doing.

On the other hand, solar cells that can efficiently generate a necessary amount of power even under low illuminance indoors are known. Typically, there are amorphous silicon solar cells having high absorption characteristics in the wavelength region of fluorescent lamps, and they are used to operate low power consumption devices such as calculators and watches.

Amorphous silicon solar cells are thin-film solar cells and have the advantage that they can be manufactured at low cost. On the other hand, the thin film type is structurally vulnerable to minute defects, and structural defects such as pinholes and scratches cause deterioration of electrical characteristics. The structural defect affects its own influence or other processes and reduces the parallel resistance between the electrodes of the solar cell.

This reduction in parallel resistance is not a big problem under high illuminance where a relatively large current is generated, but it significantly deteriorates the electrical characteristics of the solar cell under low illuminance where the generated current is small. Therefore, solar cells for low illuminance that can be distributed in the market at low cost are limited to small area products with a high yield, and large area products are not widely used.

As a means to solve this problem, a photoresist is applied and prebaked on a semiconductor film including a structural defect to fix the photoresist to the structural defect, and unnecessary photoresist on the semiconductor film is unfixed by ultraviolet light irradiation. Patent Document 1 discloses a method of removing a developing process and preventing a short circuit between upper and lower electrodes.

Japanese Patent Laid-Open No. 62-69566

The method of fixing the photoresist to a structural defect such as a pinhole is a wet process using a photolithography process, and there is no problem when using a glass substrate or the like for the substrate. The roll-to-roll process using a substrate or the like has been difficult to cope with.

In addition, the ratio of the area of structural defects to the entire area of the semiconductor film is very small, and the use efficiency of expensive photoresists is extremely poor.

Further, when the photoresist is applied, the structural defect may not be filled with the photoresist, or when the excess photoresist is removed, the photoresist once filled with the structural defect may be removed at the same time.

Therefore, an object of one embodiment of the present invention is to provide a method for repairing a structural defect in a semiconductor film corresponding to a roll-to-roll process. Another object is to improve the use efficiency of materials used for repairing structural defects in a semiconductor film. Another object is to improve the yield of repair of structural defects in the semiconductor film.

One embodiment of the present invention is to detect the position of a structural defect such as a pinhole or a flaw that is unintentionally formed in a semiconductor film, and to selectively form an insulating resin at the position, thereby The present invention relates to a photoelectric conversion device that can suppress defects such as leakage and leakage as much as possible and a manufacturing method thereof.

One embodiment of the present invention disclosed in this specification includes a step of forming a first electrode over a substrate, a step of forming a first impurity semiconductor layer having one conductivity type over the first electrode, A step of forming an intrinsic semiconductor layer over one impurity semiconductor layer, a step of forming a second impurity semiconductor layer having a conductivity type opposite to that of the first impurity semiconductor layer over the intrinsic semiconductor layer, and structural defects. Identifying a position of a structural defect existing in a region including the first impurity semiconductor layer, the intrinsic semiconductor layer, and the second impurity semiconductor layer, or a part of the region using a detecting means, and a liquid A step of discharging the liquid insulating resin material to the structural defect and its surroundings by using a discharging means, filling the liquid insulating resin material into the inside of the structural defect, and forming the structure so as to cover the structural defect; , Means to cure liquid insulating resin material A step of curing the liquid insulating resin material formed so as to fill and cover the structure defect, and a step of forming the second electrode on the second impurity semiconductor layer and the cured insulating resin. And a method for manufacturing a photoelectric conversion device.

In the present specification, the terms with numerals such as “first” and “second” are given for the sake of convenience in order to distinguish the elements, and are not limited numerically. It does not limit the order of the steps.

The step of identifying the position of the structural defect, the step of filling the liquid defect resin material into the structure defect and forming the cover of the structure defect, and the step of curing the liquid dielectric resin material are performed in parallel. By doing so, the processing time can be shortened.

In this specification, the “structural defect” means a defect having a defect such as a pinhole formed during film formation or a scratch formed by physical means, such as disorder of crystal structure. It does not mean the crystal defect of.

As means for detecting the structural defect, there are an image analysis method, a method of analyzing reflected light of a laser beam, and the like. Specifically, the former can use a method using a high-magnification imaging means and software for analyzing an image, and the latter can use a method using a laser displacement meter or the like.

In addition, it is preferable to use an ink jet method or a dispense method as a means for discharging the liquid. The resin material can be locally ejected to the specified pinhole position, and the resin material can be used without waste.

Further, as the insulating resin material, a thermosetting resin, an ultraviolet curable resin, or a heat combined type ultraviolet curable resin can be used. For example, an epoxy resin, a phenol resin, a silicone resin, an acrylic resin, a polyimide resin, or the like can be used.

Further, the means for curing the insulating resin material is heating, ultraviolet rays, or a combination thereof, and the throughput can be improved by locally heating or irradiating the insulating resin material covering the structural defect. it can.

Another embodiment of the present invention disclosed in this specification is a first impurity including a first electrode formed over a substrate and a first impurity semiconductor layer formed over the first electrode. A semiconductor layer; an intrinsic semiconductor layer formed on the first impurity semiconductor layer; a second impurity semiconductor layer having a conductivity type opposite to the one conductivity type formed on the intrinsic semiconductor layer; and a second impurity A second electrode formed on the semiconductor layer, and the first impurity semiconductor layer, the intrinsic semiconductor layer, and the region including the second impurity semiconductor layer, or a part of the region has a structural defect The photoelectric conversion device is characterized in that the structural defect is filled with an insulating resin, and the insulating resin is formed on the upper side of the structural defect so as to cover the structural defect.

Here, the diameter or short axis diameter of the insulating resin formed so as to cover the structural defect is preferably 1 mm or less. By making the diameter or short axis diameter of the insulating resin 1 mm or less, the current can be taken out without loss.

In the method for manufacturing a photoelectric conversion device according to one embodiment of the present invention, an insulating resin can be selectively filled with respect to structural defects such as pinholes and scratches formed unintentionally in a semiconductor film. The amount used can be reduced. Further, since there is no step of removing the insulating resin, the filling in the structural defect is not accidentally removed. Furthermore, since a wet process such as photolithography is not required, it can be used in the middle of a continuous process such as a roll-to-roll process. Therefore, it is possible to provide a photoelectric conversion device with a lower cost and higher yield than the conventional one and a manufacturing method thereof.

Sectional drawing explaining the photoelectric conversion apparatus which filled resin into the pinhole. Process sectional drawing of the photoelectric conversion apparatus which filled resin into the pinhole. Process sectional drawing of the photoelectric conversion apparatus which filled resin into the pinhole. The figure explaining the process of detecting a pinhole. Sectional drawing and top view explaining the photoelectric conversion apparatus which filled the resin into the pinhole. 10 is a process cross-sectional view illustrating a method for manufacturing a photoelectric conversion device. 10 is a process cross-sectional view illustrating a method for manufacturing a photoelectric conversion device. 10 is a process cross-sectional view illustrating a method for manufacturing a photoelectric conversion device. 10 is a process cross-sectional view illustrating a method for manufacturing a photoelectric conversion device. 10 is a process cross-sectional view illustrating a method for manufacturing a photoelectric conversion device.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the following description, and it will be easily understood by those skilled in the art that modes and details can be variously changed. In addition, the present invention is not construed as being limited to the description of the embodiments below. Note that in all the drawings for describing the embodiments, the same portions or portions having similar functions are denoted by the same reference numerals, and repetitive description thereof is omitted.

(Embodiment 1)
In this embodiment, a structure of a photoelectric conversion device which is one embodiment of the present invention and a manufacturing method thereof will be described.

FIG. 1 is a cross-sectional view of a photoelectric conversion device according to one embodiment of the present invention. The photoelectric conversion device in this embodiment includes the substrate 100, the first electrode 120, the first impurity semiconductor layer 140, the intrinsic semiconductor layer 150, the second impurity semiconductor layer 160, the second electrode 180, and the insulating resin 220. It is comprised including.

Here, in a region including the first impurity semiconductor layer 140, the intrinsic semiconductor layer 150, and the second impurity semiconductor layer 160, a pinhole 200 which is one of structural defects is formed, and is filled therewith. An insulating resin 220 is formed so as to cover it. By forming the insulating resin 220, a short circuit between the upper and lower electrode layers can be prevented.

Note that in this embodiment, in order to describe a part of the stacked structure of the photoelectric conversion device, illustration and description of an extraction electrode and the like connected to the first electrode are omitted.

As the substrate 100, a light-transmitting insulating substrate such as a glass substrate, polyethylene terephthalate (PET), or polyethylene naphthalate (PEN) can be used. Alternatively, a substrate in which an insulating film is formed on a metal substrate such as stainless steel may be used. In this embodiment mode, a glass substrate is used.

The first electrode 120 and the second electrode 180 include a light-transmitting conductive film such as indium oxide-tin oxide alloy (ITO), zinc oxide (ZnO), and tin oxide (SnO ₂ ), or aluminum, titanium, A metal film such as nickel, silver, or stainless steel can be used. The metal film is not limited to a single layer, and may be a stack of different films. For example, a laminate of aluminum and stainless steel can be used. In addition, a conductive paste such as a carbon paste, a nickel paste, a silver paste, or a molybdenum paste can be used.

In this embodiment mode, since the substrate 100 side is a light incident side, the first electrode 120 is a light-transmitting conductive indium oxide-tin oxide alloy, and the second electrode 180 is a laminate of aluminum and stainless steel. It is set as the structure which uses. When the light incident side is a surface opposite to the substrate 100 side, the material used for each electrode may be reversed. Note that a light-transmitting conductive film is used as the electrode on the light incident side, but the type of the facing electrode is not limited and can be selected as appropriate by the practitioner.

A semiconductor film having one conductivity type can be used for the first impurity semiconductor layer 140, and a semiconductor film having a conductivity type opposite to that of the first impurity semiconductor layer 140 can be used for the second impurity semiconductor layer 160. Can be used. In this embodiment mode, a p-type silicon semiconductor film is used for the first impurity semiconductor layer 140, and an n-type silicon semiconductor film is used for the second impurity semiconductor layer 160. May be used. Note that an amorphous silicon film can be used as the silicon semiconductor film, but a microcrystalline silicon film or a polycrystalline silicon film having a lower resistance is preferably used.

As the intrinsic semiconductor layer 150, an amorphous silicon semiconductor film is used. Note that in this specification, an intrinsic semiconductor refers to a so-called intrinsic semiconductor in which the Fermi level is located in the center of the band gap, and an impurity imparting p-type or n-type contained in the semiconductor is 1 × 10 ²⁰ cm ^−3. It refers to a semiconductor having the following concentration and having a photoconductivity of 100 times or more of dark conductivity. This intrinsic semiconductor includes those containing an impurity element belonging to Group 13 or Group 15 of the periodic table. An intrinsic semiconductor can also be referred to as a semiconductor having i-type conductivity.

The insulating resin 220 that fills the pinhole 200 that opens the first impurity semiconductor layer 140, the intrinsic semiconductor layer 150, and the second impurity semiconductor layer 160 and covers the pinhole 200 includes epoxy. It is preferable to use a resin, a phenol resin, a silicone resin, a polyimide resin, an acrylic resin, or the like. Further, a mixture of two or more of these resins may be used. Moreover, although the color of resin is not restricted, it is preferable that it is resin which has translucency with respect to visible light.

Here, the pinhole 200 is unintentionally formed by particles or the like in the process of forming the semiconductor layer. In FIG. 1, the pinhole 200 is illustrated so as to open the three semiconductor layers of the first impurity semiconductor layer 140, the intrinsic semiconductor layer 150, and the second impurity semiconductor layer 160. The formation process is caused by various phenomena and is not limited to this. For example, a pinhole may be formed above the intrinsic semiconductor layer 150, or a pinhole may be formed including the first electrode 120. In any case, the pinhole is a region where a layer to be originally formed is missing, and another layer is likely to enter the region. Therefore, it becomes a factor which deteriorates electrical characteristics, such as a short circuit and a leak.

Note that a flaw formed on the film surface is one of the structural defects, and causes defects as in the case of pinholes. The scratches on the film surface are mainly caused by contact with other objects, but in the Roll-to-Roll process, particles mixed in when the substrate is wound may be caused. In this case, a situation occurs in which the particles rub against the film surface, and scratches are generated on the film surface. Further, when a soft material such as a resin substrate is used for the base, scratches may occur that cause the particles to sink the film surface.

According to one embodiment of the present invention, the position of a structural defect is determined using a unit that detects a region having a structural defect, the insulating resin material is locally ejected to the region, and then the structural defect is cured. It is intended to suppress short circuit and leak through the. Hereinafter, an example of a formation process and a process of filling a resin into the pinhole will be described by taking a pinhole that is one of the structural defects as an example. Note that the above-mentioned scratch can be dealt with in the same manner.

First, the first electrode 120 is formed over the substrate 100 such as a glass substrate. Here, an indium oxide-tin oxide alloy is formed to a thickness of 100 nm using a sputtering method.

Hereinafter, an example will be described in which after the first electrode 120 is formed, the particles 240 accidentally adhere to the first electrode 120 (see FIG. 2A). The particles 240 are illustrated as spherical particles as an example, but there are various shapes regardless of size, shape, and material. For example, there are a piece of a film or a substrate, a lump that contains as a main component a constituent element of a source gas formed in a gas phase during film formation. Therefore, the size and shape of the pinhole formed are also various. Note that the size of the structural defect applicable to one embodiment of the present invention has a diameter or a minor axis diameter of less than 1 mm.

After the particles 240 are attached to the first electrode 120, a p-type microcrystalline silicon film with a thickness of 50 nm is formed as the first impurity semiconductor layer 140. In this embodiment mode, a p-type microcrystalline silicon film is formed using a plasma CVD method by mixing a doping gas containing an impurity imparting p-type conductivity with a source gas. As an impurity imparting p-type, typically, boron or aluminum which is a Group 13 element of the periodic table can be given. For example, a p-type microcrystalline silicon film can be formed by mixing a doping gas such as diborane with a source gas such as silane.

Here, the particles 240 are obstructed, and pinholes start to be formed in the first impurity semiconductor layer 140 over the first electrode 120 (see FIG. 2B).

Subsequently, an i-type amorphous silicon film having a thickness of 600 nm is formed as the intrinsic semiconductor layer 150 by plasma CVD. Silane or disilane can be used as the source gas, and hydrogen may be added. At this time, since atmospheric components contained in the film may become donors, 0.001 at. % Or more and 0.1 at. % Or less of boron (B) may be added.

Further, an n-type microcrystalline silicon film with a thickness of 100 nm is formed as the second impurity semiconductor layer 160 by a plasma CVD method. The n-type microcrystalline silicon film is formed by mixing a doping gas containing an impurity imparting n-type with a source gas. Typical examples of the impurity imparting n-type include phosphorus, arsenic, antimony, and the like, which are Group 15 elements of the periodic table. For example, an n-type microcrystalline silicon film can be formed by mixing a doping gas such as phosphine with a source gas such as silane.

Here, as long as the particle 240 does not move, the pinhole is enlarged (see FIG. 2C).

Since the particles 240 are attached to the first electrode 120 in an unstable state, the particles 240 may move due to slight vibration or airflow. Further, it may be intentionally removed through a cleaning process or the like. Such a state corresponds to FIG.

Here, if the second electrode is formed without noticing the presence of the pinhole, the first electrode 120 and the second electrode are short-circuited. In addition, depending on the timing at which the particles 240 move, the second impurity semiconductor layer 160 and the first impurity semiconductor layer 140 may be short-circuited.

Therefore, the process of detecting a pinhole is performed next. As a means for detecting a pinhole, a means for acquiring and analyzing an image, a means for analyzing reflected light of a laser beam, or the like can be used. These are effective not only as pinholes but also as means for detecting scratches and foreign matters. Of course, these include means for specifying the position of a pinhole or the like.

For example, the image analyzing means acquires an image of the surface of the semiconductor film using an imaging means such as a high-magnification camera, and detects the presence or absence of pinholes or scratches using image analysis software. For example, a laser displacement meter can be used as means for analyzing the reflected light of the laser light. A laser displacement meter is a device that can detect the position and shape of an object by irradiating the object with a laser and detecting the deviation of the reflected light.

In this embodiment mode, a laser displacement meter is used to detect a pinhole on the surface of the semiconductor film 340 formed over the substrate 100 with the configuration shown in FIG. The laser displacement meter 300 through which the laser beam 320 enters and exits moves while maintaining a distance Y from the surface of the semiconductor film 340. Therefore, when the laser beam 320 is irradiated to a portion having a pinhole in the semiconductor film 340, the reflected light is reflected. Deviation occurs and displacement is detected. Therefore, the presence or absence of a pinhole and the position of the pinhole can be detected by two-dimensionally scanning the surface of the semiconductor film 340 with the laser displacement meter 300 and analyzing the presence or absence of the displacement.

Here, as a device that scans the laser displacement meter 300 two-dimensionally, a device capable of recording the position where the pinhole is detected is used.

Next, a step of filling the pinhole 200 with the insulating resin 220 is performed using a means capable of discharging liquid (see FIG. 3B). As described above, the position where the pinhole of the semiconductor film is detected is recorded, and the liquid insulating resin material may be discharged to the position according to the recording.

An ink jet method or a dispense method can be used as a means for discharging the liquid. The ink jet method can easily adjust the discharge amount because the droplet can be made small. In addition, the dispensing method has an advantage that it is easy to select a resin material because even a liquid having a relatively high viscosity can be discharged.

As the liquid insulating resin material, it is preferable to use a thermosetting resin, an ultraviolet curable resin, or a heat combined type ultraviolet curable resin. Specific examples of these materials include epoxy resins, phenol resins, silicone resins, polyimide resins, and acrylic resins. After discharging any one of these resins or a resin in which these are mixed to the pinhole, the thermosetting resin is heated and cured, and the ultraviolet curable resin is cured by irradiation with ultraviolet rays. Further, in the case of a heat combined type ultraviolet curable resin, it is cured by heating after irradiation with ultraviolet rays.

For example, by using a dispensing method, an ultraviolet curable resin combined with heat is discharged to a pinhole, irradiated with 10 J / cm ² of ultraviolet light, and cured by heating at 125 ° C. for 10 minutes.

The means for curing the insulating resin material may be performed on the entire substrate, but may be locally performed on the insulating resin material covering one or a plurality of pinholes. By performing processing locally, the throughput can be improved.

Further, as the insulating resin material, a thermoplastic resin, a solvent volatile resin, or the like can be used. If these are used, the process of curing the resin can be omitted. However, you may perform the process which promotes hardening, such as cooling and a heating.

Here, the insulating resin 220 is preferably formed so as to cover the pinhole in order to prevent filling failure. A part of the second impurity semiconductor layer 160 covered with the insulating resin 220 does not come into contact with a second electrode 180 to be described later. However, since the region has a minimal area, there is no influence on the reduction in conversion efficiency. Very few. For example, when the electric conductivity of the second impurity semiconductor layer 160 is 1 × 10 ⁻¹ S / cm or more and the film thickness is 10 nm or more, the current is lost if the diameter (X1) of the insulating resin 220 is φ1 mm or less. It can be taken out without doing.

3B illustrates a state in which the center of the pinhole 200 and the insulating resin 220 are filled with each other, the present invention is not limited thereto, and the pinhole 200 is filled with the insulating resin 220. If the insulating resin 220 is formed with the diameter (X1) or less, the positional relationship between the insulating resin 220 and the pinhole 200 is not limited.

For example, the pinhole 200 may be filled with the insulating resin 220 in the state shown in the cross-sectional view of FIG. In this case, the top view is shown in FIG. Note that FIG. 5A and FIG. 5B are not the same scale.

For long and narrow scratches, an insulating resin 220 is formed so as to cover the scratches 201 as shown in the top view of FIG. In this case, the short axis diameter (X2) of the insulating resin 220 may be 1 mm or less. The same applies to curved scratches.

Next, the second electrode 180 is formed over the second impurity semiconductor layer 160 and the insulating resin 220 filled in the pinhole 200. Here, a laminate of aluminum and stainless steel is used as the second electrode. Note that the side in contact with the second impurity semiconductor layer 160 is stainless steel.

By using the above steps, a structural defect of the semiconductor film is detected, and the insulating resin is selectively filled with the structural defect, whereby the waste of the insulating resin can be eliminated. Moreover, since these processes do not include a wet process, they can be easily introduced in the middle of a continuous process such as a Roll-to-Roll process.

This embodiment can be implemented in appropriate combination with the structures described in the other embodiments.

(Embodiment 2)
In this embodiment, a method for integrating a photoelectric conversion device which is one embodiment of the present invention will be described.

The photoelectric conversion device according to one embodiment of the present invention is a thin film type and can be easily integrated to extract a desired voltage. In this embodiment mode, a method for manufacturing an integrated photoelectric conversion device including the structural defect filling step described in Embodiment Mode 1 will be described.

Note that in this embodiment, unlike the example described in Embodiment 1, a configuration in which the side opposite to the substrate side is the light incident side will be described as an example. Of course, a configuration similar to that of the first embodiment is also possible. As a material that can be used for the structure of the photoelectric conversion device described in this embodiment, the same material as that of the photoelectric conversion device described in Embodiment 1 can be used. Also in this embodiment, a description is given using a pinhole as an example of a structural defect.

First, the first electrode 420 is formed over the substrate 400. Here, a polyethylene naphthalate (PEN) substrate made of a resin material is used for the substrate 400. Although the thickness of the substrate 400 is not particularly limited, for example, a roll-to-roll process can be performed if a thin substrate having a thickness of about 100 μm is used.

The Roll-to-Roll process includes not only film forming processes such as sputtering and plasma CVD, but also processes such as screen printing and laser processing. Therefore, almost all manufacturing steps of the photoelectric conversion device can be performed by a Roll-to-Roll process. Further, the process up to the middle may be performed by a Roll-to-Roll process, divided into sheets, and the subsequent processes may be performed on a sheet basis. For example, the cut sheet can be handled in the same manner as a glass substrate or the like by sticking it to a frame formed of ceramic, metal, or a composite thereof.

The first electrode 420 is formed by a sputtering method. Here, a metal film in which aluminum having a thickness of 300 nm and stainless steel having a thickness of 5 nm are sequentially stacked is used for the first electrode 420.

Hereinafter, an example will be described in which the particles 540 are accidentally attached to the first electrode 420 after the first electrode 420 is formed (see FIG. 6A). The particles 540 are illustrated as spherical as an example, but there are various forms regardless of size, shape, and material.

Next, the first impurity semiconductor layer 440 is n-type microcrystalline silicon with a thickness of 100 nm, the intrinsic semiconductor layer 450 is i-type amorphous silicon with a thickness of 600 nm, and the second impurity semiconductor layer 460 is a film. A p-type microcrystalline silicon having a thickness of 50 nm is sequentially formed using a plasma CVD method. Here, the pinhole 500 is formed by the particles 540 (see FIG. 6B).

Since the particles 540 are attached to the first electrode 420 in an unstable state, the particles 540 may move due to slight vibration or airflow. Further, it may be intentionally removed through a cleaning process or the like. Such a state corresponds to FIG.

Next, a step of detecting pinholes in the semiconductor layer is performed using means for detecting structural defects. As the means for detecting the structural defect, the means described in the first embodiment can be used.

After detecting the pinhole in the semiconductor layer, the pinhole is filled with the first insulating resin 520 and cured (see FIG. 7A). As this means, the means described in the first embodiment can be used. At this time, when processing a large area, the step of specifying the position of the pinhole, the step of filling the pinhole with insulating resin and covering the pinhole, and the step of curing the insulating resin It is preferable to carry out in parallel on the same substrate. Processing time can be shortened by performing a plurality of processes simultaneously.

Next, a detailed description for integrating the photoelectric conversion devices will be given.

First, second insulating resins 600a, 600b, 600c, 600d, 600e, and 600f are formed over the second impurity semiconductor layer 460 (see FIG. 7B). The second insulating resins 600a, 600c, and 600e have an action of promoting the absorption of laser light when the stacked semiconductor layers and electrodes are divided. The second insulating resins 600b, 600d, and 600f It acts as a stopper when the single layer of the translucent conductive film as an electrode is divided.

The insulating resin is preferably formed by a screen printing method, and a thermosetting resin such as an epoxy resin can be used. The resin is preferably black in order to promote the above-described absorption of laser light.

Next, a second electrode 480 is formed over the second impurity semiconductor layer 460 and the insulating resin by a sputtering method (see FIG. 7C). For example, an indium oxide-tin oxide alloy with a thickness of 100 nm can be used for the second electrode 480.

Next, as a process for dividing the element, laser light is irradiated to form separation holes (see FIG. 8A). Each of the first separation holes 620a, 620b, and 620c is formed by irradiating a laser beam to the stacked portion of the second electrode 480 and the second insulating resin 600a, 600c, and 600e, and stacked semiconductors The layer and the first electrode are separated. Here, a part of the separation hole may reach the substrate 400.

Each of the second separation holes 640a, 640b, and 640c is formed by irradiating the stacked portion of the second electrode 480 and the second insulating resin 600b, 600d, and 600f with laser light. Only the electrode 480 is divided. Here, grooves may be formed in a part of the second insulating resins 600b, 600d, and 600f.

Here, it is preferable to use a continuous wave or pulsed laser in the visible light region or the infrared light region as the laser used in these laser irradiation steps. For example, a fundamental wave (wavelength 1064 nm) or a second harmonic wave (wavelength 532 nm) of an Nd-YAG laser can be used.

Next, third insulating resins 660a, 660b, 660c, 660d, 660e, and 660f that seal the first separation holes 620a, 620b, and 620c and the second separation holes 640a, 640b, and 640c are formed (FIG. 8 (B)). The insulating resin can be formed using the same method and material as the second insulating resins 600a, 600b, 600c, 600d, 600e, and 600f.

Next, third electrodes 680a, 680b, and 680c are formed. The third electrode 680a is formed so as to be in contact with the second electrode 480 between the third insulating resin 660a and the third insulating resin 660b. The third electrode 680b is formed so as to extend in the direction of the third insulating resin 660c with the third insulating resin 660d as an end and to be in contact with the second electrode 480 of the adjacent cell. The third electrode 680c is formed to extend in the direction of the third insulating resin 660e with the third insulating resin 660f as an end and to be in contact with the second electrode 480 of the adjacent cell.

The third electrodes 680a, 680b, and 680c can be formed by a screen printing method. As the material, a thermosetting conductive paste is preferably used. For example, a silver paste or the like can be used.

After that, laser light is irradiated from above the third electrodes 680a, 680b, and 680c to form connection holes 700a, 700b, and 700c (see FIG. 8C). The connection hole is a region where the first electrode 420 is welded to each of the third electrodes 680a, 680b, and 680c.

Here, the third electrode 680a functions as an extraction electrode for extracting the first electrode 420 to the surface side. The third electrode 680b acts as a connection electrode that connects adjacent cells in series. The third electrode 680 c functions as an extraction electrode for the second electrode 480. Here, even though the connection hole 700c is not formed, it functions as an extraction electrode. However, since a part of the third electrode 680c can be connected to the first electrode 420 to reduce resistance, the connection hole 700c Is preferably formed. Note that, in this embodiment, an integration process in which two cells are connected in series is described as an example. However, the number of cells to be integrated is not limited to this, and a practitioner can appropriately determine.

Further, as shown in FIG. 9, a grid electrode 720 may be formed by extending a part of each of the third electrode 680b and the third electrode 680c in the direction of the adjacent cell. By forming the grid electrode 720, resistance loss can be reduced, and electrical characteristics particularly under high illuminance can be improved. Note that the grid electrode 720 is formed at an interval in the depth direction of the drawing and does not cover the entire light receiving surface. FIG. 9 illustrates a cross section of a region where the grid electrode 720 is formed.

Although not shown, a translucent insulating resin may be provided on the light receiving surface side as a sealing resin in order to improve reliability. The sealing resin can be formed by a screen printing method, and a thermosetting epoxy resin, a phenol resin, or the like can be used.

Through the above steps, an integrated photoelectric conversion device that can suppress defects such as short circuits and leaks as much as possible with a high yield can be manufactured.

This embodiment can be implemented in appropriate combination with the structures described in the other embodiments.

(Embodiment 3)
In this embodiment, a method for integrating photoelectric conversion devices, which is different from that in Embodiment 2, will be described.

In this embodiment, a configuration in which the substrate side is the light incident side will be described as an example. As a material that can be used for the structure of the photoelectric conversion device described in this embodiment, the same material as that of the photoelectric conversion device described in Embodiments 1 and 2 can be used. Also in this embodiment, a description is given using a pinhole as an example of a structural defect.

In this embodiment mode, a process for forming a semiconductor layer and a process for forming a pinhole 500 in the semiconductor layer are the same as those in Embodiment Mode 2, and FIGS. 6A, 6B, and 6C and the description thereof. Please refer to.

However, as described above, the present embodiment describes a configuration example in which the substrate side is the light incident side. Therefore, in the process until the pinhole 500 is formed in the semiconductor layer, a light-transmitting conductive film is used for the first electrode 420, and p-type microcrystalline silicon is used for the first impurity semiconductor layer 440. This is different from Embodiment Mode 2 and in that n-type microcrystalline silicon is used for the second impurity semiconductor layer 460. Each film thickness is the same as in the second embodiment.

In addition, a step of detecting a pinhole in the semiconductor film in which the pinhole 500 is formed, and a step of filling the detected pinhole with a liquid insulating resin material and curing it to form a first insulating resin 520. Is the same as that in Embodiment 2, and FIG. 7A and the description thereof are referred to.

Next, a detailed description for integrating the photoelectric conversion devices will be given.

First, the first separation holes 820a, 820b, 820c, and the second separation holes are formed for the first electrode 420, the first impurity semiconductor layer 440, the intrinsic semiconductor layer 450, and the second impurity semiconductor layer 460. 840a, 840b, and 840c are formed (see FIG. 10A).

The separation hole can be formed by a laser irradiation step similar to that in Embodiment 2, and the first electrode 420, the first impurity semiconductor layer 440, the intrinsic semiconductor layer 450, and the second impurity semiconductor layer 460 are formed. Divide all layers.

Next, second insulating resins 860a, 860b, and 860c that seal the first separation holes 820a, 820b, and 820c are formed (see FIG. 10B). The insulating resin can be formed using a method and a material similar to those of the second insulating resins 600a, 600b, 600c, 600d, 600e, and 600f described in Embodiment 2.

Next, second electrodes 880a, 880b, and 880c are formed. The second electrode 880a is formed so as to fill the second separation hole 840a. The second electrode 880b fills the second separation hole 840b, extends in the direction of the second insulating resin 860b, and is formed so as to be connected to the second impurity semiconductor layer 460 of an adjacent cell with a large area. To do. The second electrode 880c fills the second separation hole 840c, extends in the direction of the second insulating resin 860c, and is formed so as to be connected to the second impurity semiconductor layer 460 of an adjacent cell with a large area. To do.

The second electrodes 880a, 880b, and 880c can be formed by a screen printing method. As the material, a thermosetting conductive paste is preferably used. For example, a silver paste or the like can be used.

Here, the second electrode 880a functions as an extraction electrode for extracting the first electrode 420 to the surface side. The second electrode 880b is an electrode facing the first electrode 420, and also functions as a connection electrode that connects adjacent cells in series. The second electrode 880c is an electrode facing the first electrode 420 and functions as an extraction electrode. Here, the formation of the second separation hole 840c is not essential, but a part of the second electrode 880c can be connected to the first electrode 420 to reduce the resistance. Preferably, 840c is formed. Note that, in this embodiment, an integration process in which two cells are connected in series is described as an example. However, the number of cells to be integrated is not limited to this, and a practitioner can appropriately determine.

Although not shown, an insulating resin may be provided as a sealing resin on the surface on which the second electrodes 880a, 880b, and 880c are formed in order to improve reliability. Further, a light-transmitting insulating resin may also be provided on the surface of the substrate 400 on the light receiving surface side (the bottom surface side in FIG. 10). The translucent insulating resin can act as an antireflection film in addition to filling scratches on the surface of the substrate 400. The insulating resin and the light-transmitting insulating resin can be formed by a screen printing method, and a thermosetting epoxy resin or the like can be used.

Through the above steps, an integrated photoelectric conversion device that can suppress defects such as short circuits and leaks as much as possible with a high yield can be manufactured.

This embodiment can be implemented in appropriate combination with the structures described in the other embodiments.

100 substrate 120 first electrode 140 first impurity semiconductor layer 150 intrinsic semiconductor layer 160 second impurity semiconductor layer 180 second electrode 200 pinhole 201 flaw 220 insulating resin 240 particle 300 laser displacement meter 320 laser light 340 semiconductor film 400 Substrate 420 First electrode 440 First impurity semiconductor layer 450 Intrinsic semiconductor layer 460 Second impurity semiconductor layer 480 Second electrode 500 Pinhole 520 First insulating resin 540 Particle 720 Grid electrode 600a Second insulating resin 600b Second insulating resin 600c Second insulating resin 600d Second insulating resin 600e Second insulating resin 600f Second insulating resin 620a First separation hole 620b First separation hole 620c First separation hole 640a First Second separation hole 640b second separation hole 640c second Separation hole 660a Third insulating resin 660b Third insulating resin 660c Third insulating resin 660d Third insulating resin 660e Third insulating resin 660f Third insulating resin 680a Third electrode 680b Third electrode 680c Third electrode Third electrode 700a Connection hole 700b Connection hole 700c Connection hole 820a First separation hole 820b First separation hole 820c First separation hole 840a Second separation hole 840b Second separation hole 840c Second separation hole 860a First separation hole 860a Second insulating resin 860b Second insulating resin 860c Second insulating resin 880a Second electrode 880b Second electrode 880c Second electrode

Claims (12)

Forming a first electrode on a substrate;
Forming a first impurity semiconductor layer having one conductivity type on the first electrode;
Forming an intrinsic semiconductor layer on the first impurity semiconductor layer;
Forming a second impurity semiconductor layer having a conductivity type opposite to that of the first impurity semiconductor layer on the intrinsic semiconductor layer;
Using a means for detecting a structural defect, the position of the structural defect existing in the region including the first impurity semiconductor layer, the intrinsic semiconductor layer, and the second impurity semiconductor layer, or a part of the region is specified. And a process of
Using a means for discharging a liquid, a liquid insulating resin material is discharged to the structural defect and its surroundings to fill the inside of the structural defect and cover the structural defect. The process of forming
Using the means for curing the liquid insulating resin material, curing the liquid insulating resin material formed so as to fill the structural defects and cover the structural defects;
Forming a second electrode over the second impurity semiconductor layer and the cured insulating resin. A method for manufacturing a photoelectric conversion device, comprising: 2. The step of identifying the position of the structural defect, the step of filling the liquid insulating resin material into the structure defect and covering the structural defect, and the liquid insulating resin according to claim 1. A method for manufacturing a photoelectric conversion device, wherein a step of curing a material is performed in parallel. The method for manufacturing a photoelectric conversion device according to claim 1, wherein the structural defect is a pinhole or a scratch. 4. The method for manufacturing a photoelectric conversion device according to claim 1, wherein an image analysis method or a method of analyzing reflected light of laser light is used as the means for detecting the structural defect. 5. 5. The method for manufacturing a photoelectric conversion device according to claim 1, wherein the means for discharging the liquid is an ink-jet method or a dispensing method. 6. The method for manufacturing a photoelectric conversion device according to claim 1, wherein the insulating resin material is a thermosetting resin, an ultraviolet curable resin, or a heat combined ultraviolet curable resin. The means for curing the insulating resin material according to any one of claims 1 to 6 is heating, ultraviolet rays, or a combination thereof, and locally heating the insulating resin material covering the structural defect, or A method for manufacturing a photoelectric conversion device, characterized by performing ultraviolet irradiation. 8. The method for manufacturing a photoelectric conversion device according to claim 1, wherein the diameter or minor axis diameter of the cured insulating resin is 1 mm or less. A first electrode formed on a substrate;
A first impurity semiconductor layer having one conductivity type formed on the first electrode;
An intrinsic semiconductor layer formed on the first impurity semiconductor layer;
A second impurity semiconductor layer formed on the intrinsic semiconductor layer and having a conductivity type opposite to that of the first impurity semiconductor layer;
A second electrode formed on the second impurity semiconductor layer;
Have
A structural defect exists in a region including the first impurity semiconductor layer, the intrinsic semiconductor layer, and the second impurity semiconductor layer, or a part of the region, and the structural defect is filled with an insulating resin. The photoelectric conversion device is characterized in that the insulating resin is formed on the upper side of the structural defect so as to cover the structural defect. The photoelectric conversion device according to claim 9, wherein the structural defect is a pinhole or a scratch. 11. The photoelectric conversion device according to claim 9, wherein the insulating resin is formed of an ultraviolet curable resin or a thermosetting resin. 12. The photoelectric conversion device according to claim 9, wherein a diameter or a short axis diameter of the insulating resin formed so as to cover the structural defect is 1 mm or less.

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