JP2009071192A - Photoelectric conversion device and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technology capable of preventing damage caused by a hot spot phenomenon by making the simple modification of a structure. <P>SOLUTION: The photoelectric conversion device is provided with: a plurality of photoelectric conversion cells disposed on a substrate, and a bypass wherein the plurality of photoelectric conversion cells have photoelectric conversion layers for receiving light and converting the light into power; a transparent electrode layer formed at a light incident surface side so as to sandwich the photoelectric conversion layer; and a rear surface electrode layer formed reversely to the light incident surface, and the transparent electrode layer and the rear surface electrode layer are divided by split grooves so as to correspond to the plurality of photoelectric conversion cells, and the rear surface electrode layer is connected to the transparent electrode layer of each adjacent photoelectric conversion cell so that the plurality of photoelectric conversion cells may be electrically connected in series. In the photoelectric conversion element, the bypass is provided so as to fill at least a part of the split grooves so that the transparent electrode layers or the rear surface electrode layers of the adjacent photoelectric conversion cells may be connected to each other, respectively. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a photoelectric conversion device and a manufacturing method thereof, and more particularly, to a thin film solar cell and a manufacturing method thereof.

  As a photoelectric conversion device that receives light and extracts electric power, a photoelectric conversion device in which a plurality of photoelectric conversion cells are electrically connected in series is known in order to increase a generated voltage. An example of such a photoelectric conversion device is a solar cell.

  Solar cells are usually installed outdoors. At that time, a part of the light incident surface may become a shadow of a building or a tree. As a result, only some of the plurality of photoelectric conversion cells connected in series may be shielded from light. A cell that normally receives light generates power to generate photovoltaic power. On the other hand, the photovoltaic power is reduced in the light-shielded cell. The light-shielded cell is applied with a voltage due to the photovoltaic force of the cell that has received light normally. As a result, the light-shielded cell behaves as a diode connected with the normal power generation direction as the reverse direction. When a voltage higher than the withstand voltage of the reverse voltage of the cell is applied to the light-shielded cell, dielectric breakdown occurs and the current flows as a reverse current. At this time, a reverse current may begin to flow in a location where the withstand voltage of the reverse voltage is low, and local Joule heating may occur. Since the resistance of the reverse voltage is further reduced at the heat generating portion, the reverse current flows intensively and heat generation increases. Such a phenomenon is called a hot spot phenomenon. Due to local heating of the solar cell due to the hot spot phenomenon, the cell itself may be damaged, or a support substrate exemplified by glass may be damaged due to a temperature difference from the surroundings. A technique capable of preventing damage due to the hot spot phenomenon is desired.

  Techniques relating to measures against the hot spot phenomenon are described in Patent Documents 1 to 5.

  Patent Document 1 describes that in a plurality of photoelectric conversion cells connected in series, a back electrode surface of an arbitrary cell and a back electrode surface of an adjacent cell are connected by a bypass tape.

  Patent Document 2 includes a plurality of series arrays formed by connecting a plurality of thin film photoelectric conversion cells in series, and a pair of common electrodes that connect the plurality of series arrays in parallel, and each of the series arrays has a short-circuit current. A thin film photoelectric conversion module having a current of 600 mA or less is disclosed.

  Patent Document 3 discloses a transparent front electrode provided on a substrate, a thin film photoelectric conversion unit provided on the transparent front electrode, a transparent oxide layer provided on the thin film photoelectric conversion unit, A metal back electrode provided on the transparent oxide layer, and a metal part in contact with one surface of the thin film photoelectric conversion unit in a part of a region sandwiched between the transparent front electrode and the metal back electrode. A thin film photoelectric conversion module is disclosed.

  Patent Document 4 includes a plurality of thin film photoelectric conversion cells connected in series, and a plurality of bypass diodes connected in parallel with each of the n thin film photoelectric conversion cells connected in series. A thin film photoelectric conversion module is disclosed.

  Further, Patent Document 5 discloses a first conductivity type layer formed on the light receiving surface side of the substrate, a second conductivity type electrode formed on the back surface side of the substrate, a first conductivity type layer, and a first conductivity type layer. A solar cell element having a bypass electrode formed so as to be in contact with two conductivity type electrodes is disclosed.

JP 2006-5020 JP JP 2001-68713 A JP 2001-85709 A JP 2001-68696 A JP 2006-4999 A

  The technology described in the above-mentioned patent document prevents heat generation due to a large reverse current flowing into a light-shielded cell by reducing a short-circuit current or providing a bypass passage with a bypass diode or the like for a reverse voltage. . However, such a technique involves a large structural change, which complicates the manufacturing process. In addition, there has been a problem in improving the reliability such that individual characteristic differences occur in the bypass passage with respect to the reverse voltage and the power generation amount is reduced due to imbalance of the bypass passage.

  That is, in order to improve the reliability by taking measures against the hot spot phenomenon, it is necessary to greatly change the structure to make the manufacturing process complicated, and the manufacturing cost has increased.

  Accordingly, an object of the present invention is to provide a technique capable of preventing damage due to a hot spot phenomenon by a simple structural change.

  [Means for Solving the Problems] will be described below using the numbers and symbols used in [Best Mode for Carrying Out the Invention]. These numbers and symbols are added in parentheses in order to clarify the correspondence between the description of [Claims] and [Best Mode for Carrying Out the Invention]. However, these numbers and symbols should not be used for the interpretation of the technical scope of the invention described in [Claims].

  The photoelectric conversion apparatus of this invention comprises the some photoelectric conversion cell (4) arrange | positioned on a board | substrate (3), and a bypass part (8). Each of the plurality of photoelectric conversion cells (4) includes a photoelectric conversion layer (42) that receives light and converts it into electric power, and a transparent electrode provided on the light incident surface side so as to sandwich the photoelectric conversion layer (42). A layer (41), and a back electrode layer (43) provided on the side opposite to the light incident surface. The transparent electrode layer (41) and the back electrode layer (43) are each divided corresponding to the plurality of photoelectric conversion cells by dividing grooves. The back electrode layer (43) is connected to the transparent electrode layer (41) of each adjacent photoelectric conversion cell (4) so that the plurality of photoelectric conversion cells (4) are electrically connected in series. The bypass portion (8) is provided so as to fill at least a part of the dividing groove so as to connect the transparent electrode layers (43) or the back electrode layers (43) of the adjacent photoelectric conversion cells (4). It has been.

  According to such a configuration, even if a reverse bias voltage, which is a reverse voltage, is applied to the light-shielded photoelectric conversion cell (4), it does not pass through the photoelectric conversion layer (42) but via the bypass unit (8). And a lot of reverse current flows. In the light-shielded photoelectric conversion cell (4), it is possible to prevent reverse current from flowing in one place and further concentrate due to heat generation, thereby suppressing local heat generation. Here, a reverse bias voltage is applied to the light-shielded photoelectric conversion cell (4) by a simple structural change in which the transparent electrode layers (41) or the back surface electrodes (43) are connected by the bypass unit (8). Local heat generation can be suppressed.

In the above-mentioned Patent Document 1, since a bypass tape is installed on the surface of the back electrode, a step of installing the bypass tape must be added. On the other hand, in the present invention, the bypass portion is provided so as to fill at least a part of the dividing groove. The bypass portion provided in such a dividing groove can be created, for example, only by changing the laser etching conditions when forming the dividing groove, and does not involve a large manufacturing process.
In the above-mentioned Patent Document 2, a plurality of cells are connected in series to form a series array, and the series arrays are connected in parallel by a pair of common electrodes, and a complicated structure is adopted. Yes. On the other hand, in the present invention, the bypass portion is only provided so as to fill the dividing groove, and there is no need to connect a plurality of series arrays in parallel. A complicated structure of connecting a plurality of serial arrays in parallel is not necessary, and local heat generation can be suppressed with a simple structure.
Moreover, in the above-mentioned patent document 3, the metal part which contacts one surface of a thin film photoelectric conversion unit is provided in a part of area | region pinched by the transparent front electrode and its metal back electrode. The metal part is for causing a short circuit between the metal back electrode layer and the transparent front electrode layer immediately, and between the adjacent photoelectric conversion cells as in the present invention, between the transparent electrode layers or the back electrode layer. It is not for connecting each other.
In Patent Document 4 described above, a plurality of cells connected in series are connected in parallel by a bypass diode. Such a structure is a complicated structure due to the addition of a bypass diode and the parallel connection of a plurality of cells connected in series. Need to change. On the other hand, according to the present invention, it is not necessary to add a large manufacturing process as described above.
Further, in Patent Document 5 described above, the bypass electrode must connect the first conductivity type layer provided on the main surface of the substrate and the second conductivity type layer provided on the back surface. Therefore, the bypass electrode is also provided on the side surface of the substrate, and the structure is complicated. On the other hand, according to the present invention, it is not necessary to provide a bypass portion on the side surface of the substrate, and local heat generation can be suppressed with a simple structure.

  The bypass section between two adjacent photoelectric conversion cells is a part of the separation groove of the transparent electrode layer or the separation groove of the back electrode layer formed when the photoelectric conversion cells are electrically connected in series. It is preferable that the transparent electrode layers or the back electrode layers of the two adjacent photoelectric conversion cells are electrically connected to each other without forming them.

  Between the transparent electrode layers (41) or between the back surface electrodes (43), the bypass portion (8) causes electric separation in the separation groove (7) of the transparent electrode layer (41) or the separation groove (18) of the back surface electrode layer (43). Therefore, the contact resistance is reduced to reduce the unbalance of the electrical resistance value in each bypass part, resulting in a reliable connection of the bypass part. Even if a certain reverse bias voltage is applied, most of the reverse current flows through the bypass unit (8) reliably, not the photoelectric conversion layer (42), and reversely flows to the light-shielded photoelectric conversion cell (4). Concentration of current can be prevented, and local heat generation can be reliably suppressed.

  Moreover, it is preferable that the electrical resistance value of the bypass part (8) between two adjacent photoelectric conversion cells (4) is smaller than the electrical resistance value with respect to the reverse voltage of the dark state of each photoelectric conversion cell (4).

  If the electrical resistance value of the bypass section (8) is too small, a current flows between the adjacent photoelectric conversion cells (4) via the bypass section (8) even during normal power generation, resulting in a leakage current. This is due to battery characteristics, particularly F.I. F. (Curvature factor) is worsened. Usually, it is preferably higher than the electric resistance value of each photoelectric conversion cell (4) in the bright state (power generation state). Moreover, a reverse bias voltage is applied to the light-shielded photoelectric conversion cell (4) by making the electrical resistance value of the bypass unit (8) smaller than the electrical resistance value of each photoelectric conversion cell (4) in the dark state. In this case, a current can selectively flow through the bypass portion (8). For this purpose, it is more preferable to set the photoelectric conversion cell (4) to an electrical resistance value or less in the dark state.

  Moreover, the length of the longitudinal direction of the photoelectric conversion cell which totaled the part in which the bypass part (8) was provided between adjacent photoelectric conversion cells (4) is the sum total of the part in which the bypass part (8) is not provided. It is preferably smaller than the length of the photoelectric conversion cell in the longitudinal direction.

  By making the length in the longitudinal direction of the photoelectric conversion cell of the bypass part (8) smaller than the part without the bypass part (8), the current through the bypass part (8) can be ignored during normal power generation. Can be reduced as much. Thereby, battery characteristics due to leakage current, particularly F.D. F. Deteriorating (curvature factor) is extremely reduced. Further, when a reverse bias voltage, which is a reverse voltage, is applied to the light-shielded photoelectric conversion cell (4), most of the reverse current can selectively flow through the bypass section (8).

  Further, when each of the plurality of photoelectric conversion cells (4) is formed in a strip shape, the position of the bypass portion (8) provided in one between the photoelectric conversion cells (4) is the adjacent photoelectric conversion. It is preferable that the position of the bypass part (8) provided between the cells (4) is different from the longitudinal direction of each photoelectric conversion cell (4). By arranging the bypass unit (8) in this way, the position where the reverse current flows can be dispersed throughout the plurality of photoelectric conversion cells (4) arranged on the substrate (3). As a result, a light-shielded photoelectric conversion cell (4) is generated at any position of the plurality of photoelectric conversion cells (4) arranged on the substrate (3), and the light-shielded photoelectric conversion cell (4) is reversed. Even when a reverse bias voltage, which is a directional voltage, is applied, local heat generation can be further suppressed.

  From one viewpoint, the bypass portion (8) is a portion where the transparent electrode layer (41) does not form the separation groove (7) of the transparent electrode layer (41) so that the transparent electrode layer (41) is partially connected between the adjacent photoelectric conversion cells. It is preferable that Since the bypass portion (8) is a portion of the transparent electrode layer (41) where the separation groove (7) of the transparent electrode layer (41) is not formed, it is simple to control the position where the separation groove (7) is not formed. In addition, a highly reliable bypass portion (8) substantially free of contact resistance can be formed.

  Further, from another viewpoint, the transparent electrode layer (41) is formed such that the separation grooves (7) of the transparent electrode layer (41) are formed in a plurality of dots at the boundary between the adjacent photoelectric conversion cells (4). Preferably it is formed. At this time, the bypass portion (8) is a portion where the transparent electrode layer (41) remains between the adjacent dots. In the first place, the separation groove (7) of the transparent electrode layer (41) is formed as a continuous separation groove by superimposing dots processed by the laser light irradiated in a pulse shape, so that the pulse oscillation frequency of the laser light is increased. By adjusting the relative movement speed of the substrate (3) with the transparent electrode layer (41), a highly reliable bypass section (8) can be easily formed.

  From another viewpoint, the bypass portion (8) is preferably formed of a metal film provided in the separation groove (7) of the transparent electrode layer (41). Thus, if the bypass part (8) is formed of a metal film, the bypass part (8) and the photoelectric conversion layer (4) part are joined by Schottky connection. As a result, during normal power generation without light shielding, the bypass unit (8) has a reverse voltage, so that the loss due to a minute energization of the bypass unit (8) is further reduced, and a reverse bias is applied to the light-shielded photoelectric conversion cell (4). In some cases, a reverse current flows through the bypass portion (8), and the reverse current hardly flows through the photoelectric conversion layer (4).

  From another viewpoint, the bypass portion (8) is formed of a high resistance film having a higher resistance than the back electrode layer (43) provided in the separation groove (18) of the back electrode layer (43). Preferably it is. As a result, the contact resistance can be easily reduced by forming a high resistance film including the separation groove (18) from the surface of the back electrode layer (43) in a part between the adjacent photoelectric conversion cells (4). It is possible to form the bypass portion (8) that is highly reliable and has a small amount of minute current to be passed during normal power generation without light shielding. Further, by forming a high resistance film in the separation groove (18) between the adjacent photoelectric conversion cells (4) close to the edge of the substrate (3), the outside air moisture enters the photoelectric conversion layer region on the inner side. Since the route is blocked, it contributes to the improvement of the reliability of the solar cell panel.

  In the method for manufacturing a photoelectric conversion device of the present invention, a plurality of photoelectric conversion cells (4) are electrically connected in series, and each of the plurality of photoelectric conversion cells (4) receives light and converts it into electric power. The conversion layer (42), the transparent electrode layer (41) provided on the light incident surface side so as to sandwich the photoelectric conversion layer (42), and the back electrode layer (43 on the opposite side to the light incident surface) The back electrode layer (43) is formed on the transparent electrode layer (41) of each adjacent photoelectric conversion cell (4) so that the plurality of photoelectric conversion cells (4) are electrically connected in series. It is a manufacturing method of the connected photoelectric conversion apparatus. The photoelectric conversion device manufacturing method includes a transparent electrode layer forming step (step S10) for forming the transparent electrode layer (41), a photoelectric conversion layer forming step (step S20) for forming the photoelectric conversion layer (42), and a back surface. And a back electrode layer forming step (step S30) for forming the electrode layer (43). In the transparent electrode layer forming step (S10), the step of forming the transparent electrode layer (41) (step S11), and the formed transparent electrode layer (41) corresponds to each of the plurality of photoelectric conversion cells (4). And a patterning step of patterning the transparent electrode layer (41) so as to be divided. Here, in the patterning step, patterning is performed so that a bypass portion (8) that connects the transparent electrode layers (41) is formed in a part between the adjacent photoelectric conversion cells (4). .

  Thus, the bypass portion (8) can be formed by devising a patterning step when dividing the transparent electrode layer (41). The transparent electrode layer (41) needs to be divided corresponding to the photoelectric conversion cell (4). Therefore, the patterning of the transparent electrode layer (41) is originally a necessary process. That is, it is not necessary to add a new process to provide the bypass portion (8).

  In another embodiment of the method for producing a photoelectric conversion device of the present invention, a plurality of photoelectric conversion cells (4) are electrically connected in series, and each of the plurality of photoelectric conversion cells (4) receives light and receives power. A photoelectric conversion layer (42) for conversion into a transparent electrode layer (41) provided on the light incident surface side so as to sandwich the photoelectric conversion layer (42), and a back surface provided on the opposite side of the light incident surface The back electrode layer (43) includes a transparent electrode layer of each adjacent photoelectric conversion cell (4) so that the plurality of photoelectric conversion cells (4) are electrically connected in series. This is a method for manufacturing the photoelectric conversion device connected to (41). The photoelectric conversion device manufacturing method includes a transparent electrode layer forming step (step S10) for forming the transparent electrode layer (41), a photoelectric conversion layer forming step (step S20) for forming the photoelectric conversion layer (42), and a back surface. A back electrode layer forming step (step S30) for forming the electrode layer (43). In the back electrode layer forming step (S30), the step of forming the back electrode layer (43) and the formed back electrode layer (43) are divided corresponding to each of the plurality of photoelectric conversion cells (4). A patterning step of patterning the back electrode layer (43). Here, in the patterning step, patterning is performed so that a bypass portion (8) that connects the back electrode layers (43) to each other is formed in a part between adjacent photoelectric conversion cells (4). To do.

  A bypass part (8) can be formed by devising the patterning process at the time of dividing | segmenting a back surface electrode layer (43). The back electrode layer (43) needs to be divided so as to correspond to the photoelectric conversion cell (4). Therefore, the patterning of the back electrode layer (43) is an originally necessary process. That is, it is not necessary to add a new process to provide the bypass portion (8).

  In the patterning step, the length in the longitudinal direction of the photoelectric conversion cell in the portion where the bypass portion (8) is provided between the adjacent photoelectric conversion cells (4) is the length of the portion where the bypass portion (8) is not provided. Patterning is preferably performed so as to be smaller than the length in the longitudinal direction of the photoelectric conversion cell. By making the length in the longitudinal direction of the photoelectric conversion cell of the bypass part (8) smaller than the part without the bypass part (8), the current through the bypass part (8) can be ignored during normal power generation. Can be reduced as much. Thereby, battery characteristics due to leakage current, particularly F.D. F. Deteriorating (curvature factor) is extremely reduced. Further, when a reverse bias voltage, which is a reverse voltage, is applied to the light-shielded photoelectric conversion cell (4), a current can selectively flow through the bypass unit (8).

  In the patterning step, it is preferable to perform patterning by irradiating an object to be patterned with a laser. In the first place, the separation groove to be patterned is a continuous separation groove by superimposing the dots processed by the laser beam irradiated in a pulse shape, so that there is a pulse oscillation frequency of the laser light and the object to be patterned. By adjusting the relative movement speed of the substrate (3), the highly reliable bypass section (8) can be easily formed.

  Further, from one viewpoint, the patterning step includes a step of arranging a mask in a region where the bypass portion (8) is to be formed, and a step of irradiating a patterning target with a laser after the mask is arranged. preferable.

  In this way, if the object to be patterned is laser-etched with the mask disposed, the bypass portion (8) can be formed by a simple process.

  From another viewpoint, in the patterning step, it is preferable to perform patterning so that the bypass portion (8) is formed by switching the shutter disposed on the optical path of the laser.

  Thus, if the position irradiated with laser is controlled by switching the shutter, the bypass portion (8) can be accurately formed in a simple process.

  Further, from another viewpoint, when irradiating the laser in the patterning step, it is preferable to perform irradiation so that the laser beam is incident on the patterning target in the form of a plurality of dots spaced from each other.

  The laser is usually oscillated in a pulsed manner and irradiated. As described above, the bypass portion (8) can be provided by irradiating the laser so as to form a plurality of dots at intervals. At that time, it is only necessary to devise the laser irradiation conditions (scanning speed, pulse interval, etc.), and the bypass section (8) can be accurately provided by a simple process.

  Further, from another viewpoint, the patterning step is performed after the complete patterning step of patterning so that the objects to be patterned are completely separated between the adjacent photoelectric conversion cells (4), and after the complete patterning step. It is preferable to include a metal paste disposing step of disposing a metal paste in a region where the part is to be formed. If the bypass part (8) is formed of a metal film, the photoelectric conversion layer (42), which is a semiconductor layer, and the bypass part (8) come into contact with each other by a Schottky junction. Therefore, even when a reverse bias voltage is applied to the light-shielded photoelectric conversion cell (4), a reverse current hardly flows to the photoelectric conversion layer (42). That is, when a reverse bias voltage is applied to the light-shielded photoelectric conversion cell (4), a reverse current easily flows through the bypass unit (8). Further, even during normal power generation, it is possible to suppress a loss in which the bypass unit (8) has a reverse voltage and a minute current is leaked from the photoelectric conversion layer (42) to the bypass unit (8). This suppresses the deterioration of the characteristics (FF) of the photoelectric conversion module.

  Further, from yet another aspect, the patterning step is performed after the complete patterning step of patterning so that the objects to be patterned are completely separated between adjacent photoelectric conversion cells (4), and the complete patterning step. It is preferable to include a single pulse irradiation step in which a region to be formed with the bypass portion is irradiated with a laser with a single pulse, and adjacent patterning objects are connected to each other by a residue to be patterned.

  The residue of the electrode layer to be patterned becomes high resistance. If the bypass portion (8) is formed of a laser residue to be patterned, current can be prevented from flowing through the bypass portion (8) during normal power generation.

  Still another embodiment of the photoelectric conversion device of the present invention is a method for manufacturing a photoelectric conversion device in which a plurality of photoelectric conversion cells (4) are electrically connected in series. The photoelectric conversion device manufacturing method includes a transparent electrode layer forming step of forming a transparent electrode layer (41), a photoelectric conversion layer forming step of forming a photoelectric conversion layer (42) that receives light and converts it into electric power, A back electrode layer forming step for forming the back electrode layer (41), and a bypass part forming for forming a bypass part (8) for connecting the back electrode layers (41) to each other between the adjacent photoelectric conversion cells (4). A process. In the back electrode layer forming step, the back electrode layer is formed, and the formed back electrode layer is divided in accordance with each of the plurality of photoelectric conversion cells (4) by the dividing grooves (18). And a patterning step of patterning the back electrode layer (43). The bypass portion forming process is executed after the patterning process. In the bypass portion forming step, the bypass portion (8) is formed by forming a high resistance film (45) having a higher resistance than the back electrode layer (43) so as to fill at least part of the dividing groove (18). It is characterized by forming.

  In this way, the contact resistance can be easily achieved simply by forming a high resistance film having a higher resistance than the back electrode layer (43) so as to fill at least a part of the separation groove (18) of the back electrode layer (43). The bypass part (8) can be formed which is small and highly reliable and has a small amount of minute current to be passed during normal power generation without light shielding. Further, if a high resistance film is formed in the separation groove (18) between the adjacent photoelectric conversion cells (4) close to the end of the substrate (3), a path through which the outside air moisture enters the photoelectric conversion layer region on the inner side. This contributes to improving the reliability of the solar cell panel.

  ADVANTAGE OF THE INVENTION According to this invention, the technique which can prevent the failure | damage of the photoelectric conversion apparatus by a hot spot phenomenon by simple structure change is provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that in this specification, a solar cell is described as an example of the photoelectric conversion device. In addition, as a photoelectric conversion unit that is a plurality of photoelectric conversion cells disposed on a substrate, a photoelectric conversion module 1 in which a solar cell film is formed and power generation is possible is referred to as a photoelectric conversion module 1. Then, a solar cell panel 50 is provided that has a back sheet or a terminal box attached to the photoelectric conversion module 1 to maintain environmental resistance and can be used outdoors.

(First embodiment)
FIG. 1A is a plan view of the photoelectric conversion module 1 according to the present embodiment, and FIG. 1B is a cross-sectional view showing an XX cross section of FIG. 1A. The photoelectric conversion module 1 includes a translucent substrate 3 and a solar cell film (power generation region 6) provided on the translucent substrate 3. The solar cell film is not provided on the peripheral edge of the translucent substrate 3 (hereinafter, the surrounding region 2), and the translucent substrate 3 is exposed. The peripheral region 2 is provided to serve as an adhesive surface when a back sheet or the like is attached to the photoelectric conversion module 1.

  In the power generation region 6, the solar cell film is divided into a plurality of photoelectric conversion cells 4 (hereinafter sometimes simply referred to as cells). Each of the plurality of photoelectric conversion cells 4 has a strip shape with the Y direction as the longitudinal direction. The plurality of photoelectric conversion cells 4 are electrically connected in series. Insulating grooves 5 extending in the X direction are provided at both ends in the Y direction of the power generation region 6. In the insulating groove 5, the solar cell film is completely removed. The insulating groove 5 prevents electrical short-circuiting at the end portion of the photoelectric conversion cell 4 and allows moisture from the substrate end portion to enter the outside of the power generation region 6 or causes the power generation region 6 to be moistened. It is provided for the purpose of preventing the characteristics from being deteriorated.

  With reference to FIG. 1B, the structure of each photoelectric conversion cell 4 is demonstrated. On the translucent substrate 3, a transparent electrode layer 41, a photoelectric conversion layer 42, and a back electrode layer 43 are laminated in this order. The photoelectric conversion layer 42 is a semiconductor layer that receives light and converts it into electric power. The transparent electrode layer 41 is divided by the transparent electrode layer separation groove 7 so as to correspond to each photoelectric conversion cell 4. A photoelectric conversion layer 42 is embedded in the transparent electrode layer separation groove 7. The photoelectric conversion layer 42 is also divided by the grooves 17 so as to correspond to the respective photoelectric conversion cells 4. The groove 17 connects the back electrode layer 43 and the transparent electrode layer 41 of the adjacent photoelectric conversion cell 4 so as to be electrically connected by a component constituting the back electrode layer 43. The back electrode layer 43 is also divided by the grooves 18 so as to correspond to the respective photoelectric conversion cells 4. With such a structure, a plurality of photoelectric conversion cells 4 are electrically connected in series.

  In the present embodiment, the shape of the transparent electrode layer 41 is devised. FIG. 2 is an explanatory diagram for explaining the shape of the transparent electrode layer 41. In FIG. 2, the photoelectric conversion layer 42 and the like are actually laminated on the transparent electrode layer 41, but only the transparent electrode layer 41 is shown for convenience of explanation.

  As shown in FIG. 2, a bypass portion 8 is provided in a part between the transparent electrode layers 41 of the adjacent photoelectric conversion cells 4. The transparent electrode layers 41 of adjacent cells 4 are not completely divided by the transparent electrode layer separation grooves 7, but the transparent electrode layer separation grooves 7 are not completely separated by the bypass portion 8. So that some are connected. The bypass part 8 is the same component as the component which comprises the transparent electrode layer 41, and is the same thickness. That is, since the transparent electrode layer 41 remains in a part of the transparent electrode layer separation groove 7, the bypass portion 8 and the transparent electrode layer 41 are reliably connected with substantially no contact resistance. It is in.

  The bypass unit 8 is provided so that a reverse current hardly flows through the photoelectric conversion layer 42 when a reverse bias voltage is applied to the light-shielded photoelectric conversion cell 4. Even if a reverse bias voltage is applied to the light-shielded photoelectric conversion cell 4, most of the reverse current flows through the bypass unit 8 and hardly flows into the photoelectric conversion layer 42.

  The bypass portions 8 are preferably provided in all the transparent electrode layer separation grooves 7 (between the cells 4), but are not necessarily provided in all the transparent electrode layer separation grooves 7. Except for the case where only the specific cell 4 is shielded over the entire region, it is only necessary to prevent the reverse current from concentrating on the photoelectric conversion layer 42 part. A bypass portion 8 may be provided in the separation groove 7. Further, in a portion that is shaded and easily shielded, or a location that is easily affected when a reverse bias voltage is applied to the light-shielded photoelectric conversion cell 4, such as a region where the temperature around the solar cell panel 1 is likely to rise. Only the bypass unit 8 may be provided.

  The bypass unit 8 needs to be provided so as not to deteriorate the characteristics of the solar cell. If the electrical resistance value of the bypass unit 8 is too large, it is difficult for a reverse current to flow through the bypass unit 8 when a reverse bias voltage is applied to the light-shielded photoelectric conversion cell 4. As a result, when the reverse withstand voltage threshold is exceeded, much of the reverse current flows through the photoelectric conversion layer 42, and local heating is likely to occur. Therefore, it is desirable that the electrical resistance value of the bypass unit 8 is small enough to allow most of the reverse current to flow through the bypass unit 8 when a reverse bias voltage is applied to the light-shielded photoelectric conversion cell 4. Specifically, it is desirable that the electrical resistance value of the bypass unit 8 is smaller than the electrical resistance value in the reverse voltage direction of the cell in a state where the cell is shaded (dark state). On the other hand, if the electrical resistance value of the bypass portion 8 is too small, a current flows as a leakage current through the bypass portion 8 even when power generation is normally performed. This is because F. of solar cell characteristics. F. (Fill factor: curvature factor) is reduced, and the amount of solar cell power generation is reduced. Therefore, the electrical resistance value of the bypass unit 8 is F.D. F. It is desirable that it is large so as not to lower.

From the above viewpoint, the length in the longitudinal direction of the photoelectric conversion cell, which is the sum of the portions provided with the bypass portion, is longer than the length in the longitudinal direction of the photoelectric conversion cell, which is the sum of portions where the bypass portion is not provided. Is preferably small. Further, the bypass portion 8 is a portion of the transparent electrode layer separation groove 7 where the length of the photoelectric conversion cell in the portion where the bypass portion 8 is provided (W2 in FIG. 3 described later) is not provided. It is preferable that the length is 1/400 to 1/100 with respect to the length in the longitudinal direction of the photoelectric conversion cell (L1 in FIG. 3). In order to make such a range, for example, the length (W2) in the longitudinal direction of the photoelectric conversion cell of one bypass unit 8 is set to about 0.5 mm, and the length in the longitudinal direction of the photoelectric conversion cell of the portion not provided is provided. The length (L1) is preferably 50 to 200 mm.
Below, the specific example which installed the bypass part 8 with the length (W2) of the longitudinal direction of such a photoelectric conversion cell and the space | interval (L1) is shown.

  As shown in FIG. 3, a plurality of bypass portions 8 are provided for one transparent electrode layer separation groove 7. The thickness of the transparent electrode layer 41 is t (cm), the width in the X direction of the transparent electrode layer 41 in each cell 4 is W1 (cm), the distance between the bypass parts 8 is L1 (cm), and the Y direction of one bypass part 8 The width is W2 (cm), the distance between the cells 4 (X direction width of the bypass unit 8) is L2 (cm), the resistivity of the transparent electrode layer 41 is ρ (Ωcm), the interstage resistance is R, and the bypass unit 8 is between The cell longitudinal direction electric resistance value of the transparent electrode layer 41 of one cell 4 is R1, the cell longitudinal direction electric resistance value of the transparent electrode layer 41 of the adjacent cell 4 is R3, and the inter-cell direction electric resistance of the bypass unit 8 is Let the value be R2.

As described above, in order to allow most of the reverse current to flow through the bypass unit 8 when the reverse bias voltage is applied, the electric resistance value (total) of the bypass unit 8 between the adjacent cells 4 is set to each cell 4. The electrical resistance value in the reverse voltage direction in the dark state may be smaller. Assuming the conditions exemplified in the following (a) to (d), the electric resistance value in the reverse voltage direction in the dark state of each cell 4 is calculated.
(A) The number of photoelectric conversion cells connected in series in the photoelectric conversion module is 160, and the area of the module is 14000 cm ² .
(B) The reverse withstand voltage of one cell 4 in the photoelectric conversion module is set to 10V.
(C) The open circuit voltage Voc per photoelectric conversion cell is 0.88 V, and the short circuit current is 14 mA / cm ² .
(D) The number of cells to which a reverse bias voltage is applied by shading in the hot spot test is assumed to be 3%, and the number of cells is 5 cells.
At this time, short-circuit current of the entire photoelectric conversion module is ^{14mA / cm 2 × 14000cm 2 /160=1.22A} .
Therefore, the electrical resistance value in the reverse voltage direction when the five cells are shielded from light (dark state) is 10% of the reverse current at the maximum of the short-circuit current (1.22 × (160-5) /160=1.18 A). Is effective in preventing the reverse withstand voltage of the cell 4 from being exceeded by flowing through the bypass unit 8 that connects adjacent cells 4 of the light-shielded cell, (10 × 5) / (1.18 × 10%) = 424 (Ω / 5 cell).
Therefore, if the sum of the electrical resistance values R2 of the bypass sections 8 connecting the adjacent cells 4 is smaller than 424/5 = 85 (Ω / cell), a reverse bias voltage is applied to the light-shielded photoelectric conversion cell. However, since most of the reverse current flows through the bypass unit 8 and a reverse voltage higher than the reverse withstand voltage is not applied to the light-shielding cell, the reverse current of the cell hardly flows. The resistivity of the transparent electrode layer 41 is ρ1, ρ2, ρ3, (Ωcm) in the L1, L2, and L3 directions, and the electrical resistance value of one bypass unit 8 is ρ2 × L2 / (W2 × t). expressed. The total electrical resistance value of the bypass portion 8 between the cells 4, when the total width of the bypass portion 8 (W2) and _{W2 total,} a _{ρ2 × L2 / (W2 total ×} t).
Therefore, the width ( _W2total ) of the bypass unit 8 may be determined so that ρ2 × L2 / ( _W2total × t) <85 (Ω) is satisfied.
Illustrate specific numerical values. Assuming that the resistivity of the transparent electrode layer is ρ2 = 7 × 10 ⁻⁴ (Ωcm), L2 = 0.005 (cm), and t = 7 × 10 ⁻⁶ (cm), _W2total > 0.01 ( cm).
That is, in this example, the sum of the widths of the bypass portion 8 connecting the cells 4 adjacent _(W2) (W2 _total) is, so that it wider than 0.01 cm.

Based on the above results, the width W2 of one bypass portion 8 is set to 0.05 cm as an appropriate size as viewed from the manufacturing process so that the total width W2 _total of the bypass portion 8 is larger than 0.01 cm. Assume that
As described above, the electrical resistance value by the bypass unit 8 is F.D. F. It is preferable that it is large so as not to lower. When the width (W2) of one bypass section 8 is determined, the interstage resistance value decreases as the interval (L1) between adjacent bypass sections 8 decreases. Therefore, the interval (L1) between the adjacent bypass portions 8 is F.D. F. It is preferable that the width is as large as possible without lowering. The interstage resistance (R) of the transparent electrode layer 41 between adjacent cells 4 is obtained as R1 + R2 + R3. Therefore, R1 + R2 + R3 is F.I. F. As long as it is within a range that does not lower the temperature.
More specifically, a numerical value will be exemplified and described.
F. F. In other words, the solar cell output can be calculated as the resistance loss due to the interstage resistance (R) = R1 + R2 + R3 being within about 1% of the solar cell output.
R1 to R3 are calculated as R1 = ρ1 × L1 / (W1 × t), R2 = ρ2 × L2 / (W2 × t), and R3 = ρ3 × L1 / (W1 × t), respectively. R1 and R3 are smaller than R2 because R1 and R3 are also connected to the back electrode of the adjacent cell.
Therefore,
Formula; (0.88V × 160) ² / (R × 160)
≦ {(0.88V × 160) × 0.014A / cm 2 × 14000cm 2/160} × 1%
Accordingly, R is desirably 72 (Ω / cell) or more.
(Expression; where R = ρ1 × (L1 / 2) / (W1 × t) + ρ2 × L2 / (W2 × t) + ρ3 × (L1 / 2) / (W1 × t)))
By selecting L1 which is R for which the above holds, F. F. Can be prevented.
The value of R is based on the condition that the sum of the electrical resistance values R2 of the bypass section 8 connecting the adjacent cells 4 is 85 (Ω / cell) or less, based on the difference between the assumed numerical values. Cell) is the selection target. In reality, however, there is a slight difference in each assumed value, so that the resistance loss can be reduced without exceeding the reverse withstand voltage of the cell 4 by targeting the calculated R electrical resistance. Judge that it is possible to do the following calculations.
W2 = 0.05 cm, W1 = 0.7 cm, ρ2 = 7 × 10 ⁻⁴ (Ωcm), ρ1 = ρ3≈ρ2 × 0.1 (Ωcm), L2 = 0.005 (cm), t = 7 It is assumed that it is × 10 ⁻⁶ (cm).
At this time, the range of the interval (L1) of the bypass portion 8 that satisfies the above-described equation is L1> 4.3 (cm).
Therefore, when the width (W2) of one bypass portion 8 is 0.05 cm (0.5 mm), the interval (L1) between the bypass portions 8 may be larger than 4.3 cm (43 mm). Therefore, as described above, the width (W2) of the bypass portion is 0.5 mm, and ρ1 and ρ3 are influenced by the contact state with the back electrode layer 42 of the adjacent cell, but are approximately 1/10 to 1 of ρ2. Since the width is / 50, the width (L1) of the portion not provided is within the range of 50 to 200 mm.
The width (W2: 0.5 mm) of the portion where the bypass portion 8 is provided in the transparent electrode layer separation groove 7 is smaller than the width (L1: 50 mm to 200 mm) of the portion where the bypass portion 8 is not provided. On the other hand, it is 1/400 or more and 1/100 or less.
For example, when the length of the cell 4 (the length in the Y direction) is 140 cm, five to 28 bypass portions 8 may be provided for one transparent electrode layer separation groove 7. It will be.
If the bypass portion 8 is provided with such a width (W2) and interval (L1), the F.V. F. In the case where a reverse bias voltage is applied to one light-shielded photoelectric conversion cell, most of the reverse current can flow through the bypass unit 8 instead of the photoelectric conversion layer 42.

  Then, the formation method of the bypass part 8 is demonstrated. FIG. 4 is a flowchart showing an overall flow of a method for manufacturing a photoelectric conversion module. First, the transparent electrode layer 41 is formed on the translucent substrate 3 (step S10). Next, the photoelectric conversion layer 42 is formed on the transparent electrode layer 41 (step S20). Then, the back electrode layer 43 is formed on the photoelectric conversion layer 42 (step S30). Thereafter, processing such as polishing of the surrounding region 2 is performed, and the photoelectric conversion module 1 is manufactured.

  In this embodiment, in order to form the bypass part 8, the process (S10) of forming the transparent electrode layer 41 is devised. Below, the process (S10) which forms the transparent electrode layer 41 is explained in full detail. In forming the transparent electrode layer 41, first, the transparent electrode layer 41 is formed on the entire surface of the translucent substrate 3 (step S11). Next, the transparent electrode layer 41 is patterned to form the grooves 7 so as to be divided corresponding to the respective photoelectric conversion cells 4 (step S12). For the formation of the photoelectric conversion layer 42 (step S20) and the formation of the back electrode layer 43 (step S30), the transparent electrode layer and the back electrode layer between adjacent cells are formed by dividing each part by paraning. A step of electrically connecting in series is included, but the description is omitted here.

  FIG. 5 is an explanatory diagram showing a state of patterning the transparent electrode layer 41 (S12). The transparent electrode layer 41 is patterned by laser etching. As shown in this figure, the substrate 3 on which the transparent electrode layer 41 is formed is placed on the XY table 9. On the substrate 3, a mask 10 is disposed in a region where the bypass portion 8 is to be formed. In addition, masks 11 for protecting the XY table 9 from laser irradiated outside the range of the substrate 3 are also arranged at both ends in the Y direction of the substrate. For example, a metal plate can be used as the masks 10 and 11. In this state, the transparent electrode layer 41 is irradiated with the laser beam 12 and etched. The irradiation position of the laser beam 12 is moved by moving the XY table 9 in the Y direction while irradiating the laser beam 12. Thereby, the transparent electrode layer 41 is etched along the Y direction and divided so as to correspond to each cell 4. At this time, in the region protected by the masks 10 and 11, the transparent electrode layer 41 is not irradiated with the laser beam 12 and the transparent electrode layer 41 remains. In the region protected by the mask 10, the bypass portion 8 that connects the transparent electrode layers 41 between the adjacent photoelectric conversion cells 4 is formed. In FIG. 5, the region where the photoelectric conversion module peripheral film is scheduled to be removed is drawn, but this is for convenience of explanation, and at this stage, the transparent electrode layer 41 remains in the region where the peripheral film is scheduled to be removed. ing.

  If the bypass portion 8 is formed as shown in FIG. 5, the bypass portion 8 can be formed by a simple process. That is, at the time of laser etching, it is only necessary to protect the substrate 3 by arranging a mask, and it is not necessary to add a special process to form the bypass portion 8.

  With respect to the photoelectric conversion module 1 manufactured as described above, the maximum output Pmax, F.V. F. Was measured. As described above, as the photoelectric conversion module 1 of the present embodiment, the one in which the bypass portions 8 having a width of about 0.5 mm are provided at intervals of 100 mm between the photoelectric conversion cells is used. In the photoelectric conversion module 1, 160 photoelectric conversion cells are connected in series.

  As a result of the measurement, the characteristics of the photoelectric conversion module 1 of the present embodiment are compared with those of the case where the bypass unit 8 is not provided. F. However, the output of 99.5% was secured as Pmax. From this result, it was confirmed that the performance degradation due to the provision of the bypass portion 8 is in a range that does not substantially cause a problem.

Moreover, the hot spot test was implemented with respect to the photoelectric conversion module 1 of this embodiment. FIG. 6 is an explanatory view showing the hot spot test. As shown in FIG. 6, an optical mask was arranged on a part of the photoelectric conversion module 1, the output terminal was short-circuited, and the simulated light was irradiated for about 1 hour. And the temperature change of the photoelectric conversion module surface was measured. The width shielded by the optical mask was 5 cells. The simulated light was 1000 W / m ² .

  As a result of the hot spot test, in the photoelectric conversion module of this embodiment, a temperature increase of about 80 ° C. was observed after 1 hour. However, the solar cell member was not damaged or the substrate was cracked due to local abnormal temperature rise, and suppression of hot spot generation was confirmed. On the other hand, the same hot spot test was performed also on the photoelectric conversion module in which the bypass unit 8 was not provided. As a result, a temperature increase exceeding 100 ° C. was observed locally. That is, in the photoelectric conversion module of this embodiment, it was confirmed that the local temperature rise could be suppressed.

  As described above, according to the present embodiment, the provision of the bypass unit 8 suppresses a local temperature increase due to the hot spot phenomenon even when a reverse bias voltage is applied to one light-shielded photoelectric conversion cell. be able to.

  In forming the bypass portion 8, it is only necessary to arrange a mask when the transparent electrode layer 41 is subjected to laser etching. That is, the bypass portion 8 can be formed by a simple process.

  In addition, by appropriately setting the width and interval of the bypass unit 8, the F.V. F. The hot spot phenomenon can be suppressed even if a reverse bias voltage is applied to the light-shielded photoelectric conversion cell 4 without dropping.

(Example in the first embodiment)
Then, in order to demonstrate a structure and a manufacturing method in detail about the photoelectric conversion module 1 and solar cell panel of this embodiment, an Example is given and demonstrated.

  First, the structure of the photoelectric conversion module (photoelectric conversion apparatus) manufactured by the Example is demonstrated. FIG. 7 is a schematic view showing a configuration of a photoelectric conversion module manufactured by the method for manufacturing a photoelectric conversion module of the present invention. This photoelectric conversion module is a silicon-based solar cell, and includes a substrate 3 (translucent substrate), a transparent electrode layer 41, a solar cell photoelectric conversion layer 42, and a back electrode layer 43. Here, the silicon-based is a generic name including silicon (Si), silicon carbide (SiC), and silicon germanium (SiGe).

  Next, the manufacturing method of the solar cell panel of this invention is demonstrated. 8A to 8D are schematic views showing a method for manufacturing the solar cell panel of this example.

(1) FIG. 8A (a):
A soda float glass substrate (1.4 m × 1.1 m × plate thickness: 4 mm) is used as the substrate 3. It is desirable that the end face of the substrate is corner chamfered or rounded to prevent breakage.
(2) FIG. 8A (b):
A transparent electrode film mainly composed of a tin oxide film (SnO ₂ ) is formed as the transparent electrode layer 41 at a temperature of about 500 ° C. to 800 nm at about 500 ° C. using a thermal CVD apparatus. At this time, a texture with appropriate irregularities is formed on the surface of the transparent electrode film. As the transparent electrode layer 41, in addition to the transparent electrode film, an alkali barrier film (not shown) may be formed between the substrate 3 and the transparent electrode layer 41. As the alkali barrier film, a silicon oxide film (SiO ₂ ) is formed at a temperature of about 500 ° C. in a thermal CVD apparatus at 50 nm to 150 nm.
(3) FIG. 8A (c):
Thereafter, the substrate 3 is placed on an XY table, and the first harmonic (1064 nm) of the YAG laser is incident from the film surface side of the transparent electrode layer 41 as indicated by an arrow in the figure. The laser power is adjusted to be suitable for the processing speed, the transparent electrode film is moved relative to the substrate 3 in the direction perpendicular to the series connection direction of the cells 4, and the transparent electrode layer separation grooves 7 are formed. Laser etching is performed in a strip shape having a width of about 6 mm to 15 mm so as to be formed. At this time, as described in the above-described embodiment, a mask is disposed on the substrate 3 and laser etching is performed so that the bypass portion 8 is formed.
(4) FIG. 8A (d):
Using a plasma CVD apparatus, a p-layer film / i-layer film / n-layer film made of an amorphous silicon thin film as the photoelectric conversion layer 42 is sequentially formed in a reduced pressure atmosphere: 30 to 1000 Pa and a substrate temperature: about 200 ° C. The photoelectric conversion layer 42 is formed on the transparent electrode layer 41 using SiH ₄ gas and H ₂ gas as main raw materials. The p-layer, i-layer, and n-layer are stacked in this order from the sunlight incident side. In this embodiment, the photoelectric conversion layer 43 is a p-layer: B-doped amorphous SiC and a film thickness of 10 nm to 30 nm, an i-layer: an amorphous Si film and a film thickness of 200-350 nm, and an n-layer: p-doped microcrystalline Si. The film thickness is 30 nm to 50 nm. A buffer layer may be provided between the p layer film and the i layer film in order to improve the interface characteristics.

In the photoelectric conversion layer 42, a p-layer film / i-layer film / n-layer film made of an amorphous silicon thin film is formed as the first cell layer 42-1, and then a reduced pressure atmosphere: 3000 Pa or less, substrate temperature by a plasma CVD apparatus. : About 200 ° C., plasma generation frequency: 40 MHz to 100 MHz, a microcrystalline p layer film / microcrystalline i layer film / microcrystalline n layer film made of a microcrystalline silicon thin film as the second cell 42-3 are sequentially formed. May be.
In this embodiment, the second cell 42-3 has a microcrystalline p layer: mainly B-doped microcrystalline SiC and a film thickness of 10 nm to 50 nm, and a microcrystalline i layer: mainly microcrystalline Si, and a film thickness of 1.2 μm to 3 μm. 0.0 μm, microcrystalline n layer: mainly composed of p-doped microcrystalline Si, with a thickness of 20 nm to 50 nm.

  GZO (Ga doped ZnO) as an intermediate contact layer 42-2, which improves the contact between the first cell layer 42-1 and the second cell layer 42-3 and becomes a semi-reflective film in order to obtain current matching The film may be provided by forming a film with a sputtering apparatus with a film thickness of 20 nm to 100 nm. Further, the intermediate contact layer 42-2 may not be provided.

(5) FIG. 8A (e):
The substrate 3 is placed on an XY table, and the second harmonic (532 nm) of the laser diode-pumped YAG laser is incident from the film surface side of the photoelectric conversion layer 42 as indicated by an arrow in the figure. Pulse oscillation: 10 to 20 kHz, the laser power is adjusted so as to be suitable for the processing speed, and the lateral side of about 100 to 150 μm of the laser etching line (transparent electrode layer separation groove 7) of the transparent electrode layer 41 is formed on the groove 17. Laser etching to form The position of the laser etching line is selected in consideration of positioning intersection so as not to intersect with the etching line in the previous process.

(6) FIG. 8B (a):
As the back electrode layer 43, an Ag film / Ti film is sequentially formed by a sputtering apparatus at about 150 ° C. in a reduced pressure atmosphere. In this embodiment, the back electrode layer 43 is formed by stacking an Ag film: 200 to 500 nm and a Ti film having a high anticorrosion effect: 10 to 20 nm in this order as a protective film. For the purpose of reducing contact resistance between the n-layer and the back electrode layer 43 and improving light reflection, a GZO (Ga-doped ZnO) film is formed between the photoelectric conversion layer 42 and the back electrode layer 43 with a thickness of 50 to 100 nm, a sputtering apparatus. May be provided by forming a film.
(7) FIG. 8B (b)
The substrate 3 is placed on an XY table, and the second harmonic (532 nm) of the laser diode-pumped YAG laser is incident from the substrate 3 side as shown by the arrow in the figure. The laser light is absorbed by the photoelectric conversion layer 42, and the back electrode layer 43 is exploded and removed using the high gas vapor pressure generated at this time. Pulse oscillation: 1 to 10 kHz, the laser power is adjusted so as to be suitable for the processing speed, and the lateral side of about 250 to 400 μm of the laser etching line (transparent electrode layer separation groove 7) of the transparent electrode layer 41 is formed on the groove 18. Laser etching to form
(8) FIG. 8B (c) and FIG. 8C (a):
The power generation region is divided to eliminate the influence that the serial connection portion due to laser etching is likely to be short-circuited at the film edge around the substrate edge. The substrate 3 is placed on an XY table, and the second harmonic (532 nm) of the laser diode pumped YAG laser is incident from the substrate 3 side. The laser light is absorbed by the transparent electrode layer 41 and the photoelectric conversion layer 42, and the back electrode layer 43 explodes using the high gas vapor pressure generated at this time, and the back electrode layer 43 / photoelectric conversion layer 42 / transparent conductive layer 41 is removed. Pulse oscillation: 1 to 10 kHz, the laser power is adjusted so as to be suitable for the processing speed, and the position of 5 to 20 mm from the end of the substrate 3 is placed in the X-direction insulating groove 5 as shown in FIG. Laser etching to form At this time, the Y-direction insulating groove does not need to be provided because the film surface polishing removal processing of the peripheral region 2 of the substrate 3 is performed in a later process. FIG. 8B (c) shows a cross section in the X direction and a cross section in the Y direction for convenience in order to show the laser irradiation position.
The insulating groove 5 exhibits an effective effect in suppressing external moisture intrusion into the photoelectric conversion module 1 from the end of the solar cell panel by terminating the etching at a position 5 to 10 mm from the end of the substrate 3. Therefore, it is preferable.
In addition, although the laser beam in the above process is made into a YAG laser, there exists what can use a YVO4 laser, a fiber laser, etc. similarly.

(9) FIG. 8C (a: view from the solar cell film side, b: view from the substrate side of the light receiving surface)
In order to ensure a healthy adhesion / seal surface with the back sheet 19 through EVA or the like in the post-process, the laminated film around the substrate 3 (surrounding region 2) has a step and is easy to peel off. Remove. When removing the film over the entire periphery of the substrate 3 at 5 to 20 mm from the end of the substrate 3, the X direction is closer to the substrate end than the insulating groove 5 provided in the step of FIG. The back electrode layer 43 / photoelectric conversion layer 42 / transparent electrode layer 41 are removed by using grinding stone polishing, blast polishing, or the like on the substrate end side with respect to the groove 7 near the side portion. Polishing debris and abrasive grains were removed by washing the substrate 3.
(10) FIG. 8D (a)
At the terminal box mounting portion, an opening through window is provided in the back sheet 19 and the current collector plate is taken out. A plurality of layers of insulating materials are installed in the opening through window portion to suppress intrusion of moisture and the like from the outside.
It processes so that electric power can be taken out from the terminal box part on the back side of a solar cell panel by collecting electricity using the copper foil from the photoelectric conversion cell 4 at one end arranged in series and the photoelectric conversion cell 4 at the other end. In order to prevent a short circuit with each part, the copper foil arranges an insulating sheet wider than the copper foil width.
After the current collecting copper foil and the like are disposed at a predetermined position, an adhesive filler sheet made of EVA (ethylene vinyl acetate copolymer) or the like is disposed so as to cover the entire photoelectric conversion module 1 and not to protrude from the substrate 3. .
On the EVA, the back sheet 19 having a high waterproof effect is installed. In this embodiment, the back sheet 19 has a three-layer structure of PET sheet / AL foil / PET sheet so that the waterproof and moisture-proof effect is high.
While the back sheet 19 is disposed at a predetermined position, the EVA is crosslinked and brought into close contact with the laminator while degassing the inside in a reduced pressure atmosphere and pressing at about 150 to 160 ° C.

(11) FIG. 8D (b)
A terminal box 20 is attached to the back side of the photoelectric conversion module 1 with an adhesive.
The copper foil and the output cable of the terminal box 20 are connected with solder or the like, and the inside of the terminal box is filled with a sealing agent (potting agent) and sealed. Thus, the solar cell panel 50 is completed.
(12) FIG. 8D (c) and FIG. 8D (d)
A power generation inspection and a predetermined performance test are performed on the solar cell panel 50 formed through the steps up to FIG. 8D (b). The power generation inspection is performed using a solar simulator of AM1.5 and solar radiation standard sunlight (1000 W / m ² ).

  By the said manufacturing method, the solar cell panel used as the product using this invention was manufactured, and it confirmed that the characteristic was not different from the thing by the conventional process.

In the above embodiments, the solar cell is a single-layer amorphous silicon solar cell having an amorphous silicon photoelectric conversion layer, or the amorphous silicon photoelectric conversion layer is a top cell, and the crystalline (microcrystalline) silicon system is a bottom cell. Although the case where a tandem solar cell having a photoelectric conversion layer is used has been described, the present invention is not limited to this example.
For example, it can be similarly applied to other types of thin-film solar cells such as multi-junction solar cells in which one or more other photoelectric conversion layers are provided in addition to the top cell and the bottom cell as the photoelectric conversion layer. It is.

(Second Embodiment)
Subsequently, a second embodiment of the present invention will be described. In the present embodiment, the method for patterning the transparent electrode layer 41 is further devised as compared with the first embodiment. Since other points are the same as those in the first embodiment, description thereof will be omitted.

  FIG. 9 is an explanatory diagram showing a state when the transparent electrode layer 41 is patterned. Similar to the first embodiment, the substrate 3 having the transparent electrode layer 41 formed on the entire surface on one side is disposed on the XY table 9. At both ends of the substrate in the Y direction, masks 11 for protecting the XY table 9 from the laser irradiated outside the range of the substrate 3 are arranged. However, the mask 10 as described in the first embodiment is not disposed in the power generation region on the substrate 3. In the present embodiment, a shutter 14 is added on the optical path of the laser beam 12 oscillated from the oscillator 13. The shutter 14 is opened and closed according to an instruction from the shutter control device 15 so as to block the optical path of the laser beam 12. Further, the transparent electrode layer 41 may be substantially not etched by shifting the focus of the laser beam 12. The shutter control device 15 is exemplified by a computer, and is connected to a driving device 16 for moving the XY table 9.

  Information indicating the driving amount of the XY table 9 is notified from the driving device 16 to the shutter control device 15. Thereby, the shutter control device 15 can grasp which position on the substrate 3 is irradiated with the laser beam 12. The shutter control device 15 stores information indicating the position of the bypass portion 8 formation area in advance. The shutter control device 15 opens and closes the shutter 14 based on the driving amount of the XY table 9 so that the laser beam 12 is not irradiated to the bypass portion 8 formation region.

  According to the present embodiment, unlike the first embodiment, it is not necessary to arrange a metal plate mask or the like in the formation region of the bypass portion 8. There is no need for a protective mask, the substrate can be easily attached and detached, and there is no displacement when the protective mask is disposed. Compared with the first embodiment, processing that is simpler and more reliable is possible.

(Third embodiment)
Subsequently, a third embodiment of the present invention will be described. In the present embodiment, the method for patterning the transparent electrode layer 41 is further devised as compared with the above-described embodiments. The other points are the same as in the above-described embodiment, and thus the description thereof is omitted.

  FIG. 10A is an explanatory view showing a state when the transparent electrode layer 41 is patterned. Similar to the above-described embodiment, the substrate 3 on which the transparent electrode layer 41 is formed is disposed on the XY table 9. The laser beam 12 is generated by the oscillator 13 in a pulsed manner, irradiated onto the transparent electrode layer 41, and continuous transparent electrode layer separation is performed by superimposing dots that are etched into a dot shape by the pulsed laser beam. A groove 7 is formed. The laser beam 12 generation condition of the oscillator 13 is controlled by the laser control device 21. Further, the XY table 9 is driven by the driving device 16 at the time of laser irradiation. Thereby, the laser beam 12 is irradiated to the transparent electrode layer 41 while changing the irradiation position. In the present embodiment, the bypass portion 8 is formed by adjusting the pulse oscillation frequency of the laser beam and the relative moving speed of the substrate 3 having the transparent electrode layer 41.

  The laser control device 21 is connected to a drive device 16 that drives the XY table 9. The laser control device 21 controls the pulse interval of the laser beam 12 generated by the oscillator 13 based on the driving speed notified from the driving device 16. Specifically, as shown in FIG. 10B, the pulse interval is controlled so that the laser beam 12 is incident on the transparent electrode layer 41 in the form of spaced dots. Thereby, the transparent electrode layer 41 is etched and removed in a dot shape by the laser beam 12 of each pulse. The portion where the transparent electrode layer 41 remains between the dots becomes the bypass portion 8.

  The width of the portion where the transparent electrode layer 41 remains without being irradiated with the laser beam 12 between each pulse (bypass portion 8) is the width of the portion where the transparent electrode layer 41 is etched away by the laser beam 12 in each pulse. On the other hand, it is preferable to be in the range of 1/400 to 1/100. If it is smaller than 1/400, the electrical resistance value of the bypass unit 8 increases, and when a reverse bias voltage is applied to the light-shielded photoelectric conversion cell 4, it becomes difficult for a reverse current to flow through the bypass unit 8 and the photoelectric conversion layer is reversed. A reverse voltage exceeding the directional withstand voltage is applied, and much of the reverse current tends to flow. On the other hand, if it is larger than 1/100, a current flows through the bypass unit 8 even during normal power generation, and F.A. F. Decreases. Since the bypass portion 8 is provided in a substantially dispersed manner, the width of the bypass portion 8 is a portion where the transparent electrode layer 41 is removed by the laser beam 12 in each pulse from the viewpoint of suppressing deterioration of battery characteristics as much as possible. More preferably, the width is 1/400 to 1/200.

  By controlling the oscillation conditions of the laser beam 12 as in this embodiment, the bypass portion 8 can be easily formed. As a result, the hot spot phenomenon can be prevented from occurring as in the above-described embodiment.

  Moreover, according to this embodiment, the process of arrange | positioning a mask like 1st Embodiment is unnecessary. Thereby, it is possible to perform a simple and highly reliable process with no mask displacement.

  In addition, using the number of pulse oscillations (pulse interval) as a parameter, the relationship between the power generation characteristics (especially FF) of solar cells, interstage resistance, and hot spot heat generation can be numerically grasped. Monitoring and selection of stable production conditions.

(Fourth embodiment)
Subsequently, a fourth embodiment of the present invention will be described. In the present embodiment, the arrangement of the bypass unit 8 is devised compared to the above-described embodiment. About another point, since it can be made the same as that of above-mentioned embodiment, description is abbreviate | omitted.

  FIG. 11 is a perspective view showing the structure of the transparent electrode layer 41 of the present embodiment. Configurations on the transparent electrode layer 41 such as the photoelectric conversion layer 42 and the back electrode layer 43 are omitted for convenience of explanation.

  In the present embodiment, the bypass unit 8 is provided so as to be arranged in a staggered manner in the photoelectric conversion module 1. That is, the position of the bypass portion 8 provided in the transparent electrode layer separation groove 7 is different in the Y direction from the position of the bypass portion 8 disposed in the adjacent transparent electrode layer separation groove 7 (between the cells 4).

  As a result, the bypass unit 8 is arranged by dispersing the bypass unit 8 in the photoelectric conversion module 1. Therefore, when a reverse bias voltage is applied to the light-shielded photoelectric conversion cell 4 and a reverse current flows through the bypass unit 8, the positions where the reverse current flows are dispersed. Therefore, the occurrence of the hot spot phenomenon is further suppressed regardless of where the light-shielded position occurs in the photoelectric conversion module 1.

(Fifth embodiment)
Subsequently, a fifth embodiment of the present invention will be described. In the present embodiment, the configuration and the formation method of the bypass portion 8 are different from the above-described embodiment. In the above-described embodiment, the bypass portion 8 is a portion formed by patterning the transparent electrode layer 41, whereas the bypass portion 8 in the present embodiment is a metal film formed of a metal paste. . Since the other points can be the same as those of the above-described embodiment, detailed description thereof is omitted.

  12A and 12B are explanatory diagrams for explaining the transparent electrode layer patterning step (corresponding to step S12 of the above-described embodiment) in the present embodiment. In the present embodiment, as shown in FIG. 12A, first, the transparent electrode layer 41 is laser-etched (patterned) so as to be completely divided corresponding to each photoelectric conversion cell 4. Next, a metal paste is disposed in a region where the bypass portion is to be formed. As the metal paste, for example, Ag paste or Al paste can be used. And the arrange | positioned metal paste is dried and the bypass part 8 which consists of a metal film is formed as FIG. 12B shows. The bypass portion 8 made of a metal film is preferably provided in the transparent electrode layer separation groove 7 at a rate of one place every 50 to 200 mm. When the bypass part 8 is provided at a rate larger than one rate every 50 mm, current leaks through the bypass part 8 during normal power generation. F. Tend to decrease. On the other hand, when the reverse bias voltage is applied to the light-shielded photoelectric conversion cell 4 when the reverse bias voltage is applied to the light-shielded photoelectric conversion cell 4, the reverse current flows to the photoelectric conversion layer side when the reverse bias voltage is applied to the photoelectric conversion cell 4. Many of them are easy to flow.

  If the bypass portion 8 is formed of a metal film as in the present embodiment, the photoelectric conversion layer 42 that is a semiconductor layer and the bypass portion 8 come into contact with each other by a Schottky junction. Therefore, even when a reverse bias voltage is applied to the light-shielded photoelectric conversion cell 4, a reverse current hardly flows to the photoelectric conversion layer 42. That is, when a reverse bias voltage is applied to the light-shielded photoelectric conversion cell 4, most of the reverse current easily flows through the bypass unit 8. Further, even during normal power generation, the bypass unit 8 becomes a reverse voltage, and a loss that causes a minute current to leak from the photoelectric conversion layer 42 to the bypass unit 8 side can be suppressed. This suppresses the deterioration of the characteristics (FF) of the photoelectric conversion module.

(Sixth embodiment)
Subsequently, a sixth embodiment of the present invention will be described. In the present embodiment, the configuration and the formation method of the bypass portion 8 are different from the above-described embodiment. That is, the bypass portion 8 in the present embodiment is formed by the residue generated by the evaporation of the transparent electrode layer 41 by laser etching. Since the other points can be the same as those of the above-described embodiment, detailed description thereof is omitted.

  In the present embodiment, similarly to the fifth embodiment, when patterning the transparent electrode layer 41, first, the patterning is performed so that the transparent electrode layer 41 is completely divided. This patterning is performed by laser etching, for example.

  Subsequently, the laser beam is irradiated again with a pulse near the separation groove of the transparent electrode layer in the region where the bypass portion 8 is to be formed. Thereby, the transparent electrode layer 41 evaporates. And the transparent electrode layers 41 between the adjacent photoelectric conversion cells 4 are connected by the residue. Thereby, the bypass part 8 in this embodiment is formed. In the transparent electrode layer separation groove 7, the bypass portion 8 made of residue is preferably provided at a rate of one place every 50 to 200 mm. When the bypass part 8 is provided at a rate larger than one rate every 50 mm, current leaks through the bypass part 8 during normal power generation. F. Tend to decrease. On the other hand, when the reverse bias voltage is applied to the light-shielded photoelectric conversion cell 4 when the reverse bias voltage is applied to the light-shielded photoelectric conversion cell 4, the reverse current easily flows to the photoelectric conversion layer side.

  The residue of the transparent electrode layer 41 has a higher resistance than the transparent electrode layer 41. Therefore, the F.D. F. The decrease can be suppressed. Moreover, it is only necessary to change the number of times of laser etching, and it is not necessary to add a specially devised process for forming the bypass portion 8. Therefore, the bypass portion 8 can be formed with a simple process change.

(Seventh embodiment)
Subsequently, a seventh embodiment of the present invention will be described. In the present embodiment, the bypass portion 8 is formed of a high resistance film 45 having a higher resistance than the back electrode layer 43 provided in the separation groove 18 of the back electrode layer 43, compared to the above-described embodiment, The structure and forming method are different. In the embodiment described above, the bypass portion 8 partially forms the bypass portion 8 in the separation groove 7 of the transparent electrode layer 41, whereas the bypass portion 8 in this embodiment has the separation groove of the back electrode layer 43. 18 is a film formed by a high-resistance film 45 having a higher resistance than the back electrode layer 43 provided on 18. Since the other points can be the same as those of the above-described embodiment, detailed description thereof is omitted.

13A and 13B are explanatory diagrams for explaining the laying state of the high resistance film 45 in the present embodiment. In the present embodiment, the back electrode layer 43 / photoelectric conversion layer 42 / transparent electrode layer 41 is removed using grinding stone polishing or blast polishing over the entire circumference of the substrate 3 at 5 to 20 mm from the edge of the substrate 3, As shown in FIG. 13A, the high-resistance film 45 is provided from the back electrode layer 43 side to the photoelectric conversion module 1 (see FIG. 8C) in which the polishing scraps and abrasive grains have been removed by cleaning the substrate 3. To do.
As the high resistance film 45, four strips of a 100 mm wide strip are provided on the back electrode layer 43 side of the photoelectric conversion module 1 so that the bypass portions 8 are provided as evenly as possible. The high resistance film 45 is a film having a higher resistance than the back electrode layer 43. The high resistance film 45 is devised to reduce the contact resistance by applying a slurry-like coating liquid containing low conductive fine particles such as titanium oxide into the separation groove 18 of the back electrode layer 43 and applying it. Installed by baking at ℃. Compared to connecting the back electrode surface and the back electrode surface of an adjacent cell with the bypass tape shown in Patent Document 1 described above, the contact resistance is reduced and stable in the separation groove 18 portion of the back electrode layer 43. The highly reliable connection that has been made is greatly improved.
The high resistance film 45 has a film thickness of about 0.002 (cm) and a sheet resistance at this film thickness of 1 × 10 ⁶ (Ω / □), and L2 = 0.005 (cm). To do.
At this time, the interstage resistance is R = 1 × 10 ⁶ (Ω / □) × 0.005 (cm) / {10 (cm) × 4 (book)}
= 125 (Ω / cell)
Thus, the target of 72 (Ω / cell) or more which does not deteriorate the battery performance is satisfied.

With respect to the photoelectric conversion module 1 manufactured as described above, the maximum output Pmax, F.V. F. Was measured. As a result of the measurement, the characteristics of the photoelectric conversion module 1 of the present embodiment are compared with those of the case where the bypass unit 8 is not provided. F. However, the output of 99.6% was secured as Pmax. From this result, it was confirmed that the performance degradation due to the provision of the bypass portion 8 by the high resistance film 45 is in a range that does not cause a problem.
Moreover, the hot spot test was implemented with respect to the photoelectric conversion module 1 of this embodiment. As shown in FIG. 6, an optical mask was arranged on a part of the photoelectric conversion module 1, the output terminal was short-circuited, and the simulated light was irradiated for about 1 hour. And the temperature change of the photoelectric conversion module surface was measured. The width shielded by the optical mask was 5 cells. The simulated light was 1000 W / m ² . As a result of the hot spot test, in the photoelectric conversion module of this embodiment, a temperature rise of about 75 ° C. was observed after 1 hour, and the temperature rise was suppressed almost as in the first embodiment, but the temperature rise could be further suppressed. The reason is that the reverse current is more effectively distributed by providing the wide bypass section 8 although the resistance between the cell stages is high, and the light-shielded cell has a voltage higher than the withstand voltage of the reverse voltage of the cell. This is considered to be because a large amount of reverse current is suppressed from flowing to the light-shielded photoelectric conversion layer without applying a voltage. Moreover, the solar cell member was not damaged or the substrate was cracked due to local abnormal temperature rise, and suppression of hot spot generation was confirmed.

In addition to the slurry-like coating solution, the high resistance film 45 can be formed by a sol-gel method or by vacuum deposition such as sputtering. A coating dispersed in a solvent such as a coating film is sufficiently dried after coating. You may let them. Alternatively, a surface layer of an adhesive filler sheet made of EVA (ethylene vinyl acetate copolymer) or the like that is in close contact with the back electrode layer 43 in a later step may be provided so as to contain low conductive fine particles such as titanium oxide. .
In the present embodiment, four strips having a width of 50 mm are installed, but they may be installed on the entire surface of the back electrode layer 43. Installation over the entire surface is preferable because the reverse current is more effectively dispersed.
Furthermore, the formation of the high-resistance film 45 may be performed on the photoelectric conversion module 1 (see FIG. 8B) that has finished a series of laser etching processes, and the slurry-like coating liquid that becomes the high-resistance film 45 is applied to the back electrode. After coating into the separation groove 18 of the layer 43 so as to reduce the contact resistance and baking at about 150 ° C., the back electrode layer 43 / photoelectric layer is formed over the entire circumference of the substrate 3 at 5 to 20 mm from the end of the substrate 3. The conversion layer 42 / transparent electrode layer 41 is removed using grinding stone polishing, blast polishing, or the like, and polishing waste and abrasive grains are removed by washing the substrate 3 to form the photoelectric conversion module 1 (see FIG. 8C). You may do it.

As a result, by simply forming the high-resistance film 45 including the separation groove 18 from the surface of the back electrode layer 43 in a part between the adjacent photoelectric conversion cells 4, the contact resistance is easily reduced and the bypass is highly reliable. The part 8 can be formed. As a result, the hot spot phenomenon can be prevented from occurring as in the above-described embodiment.
Further, by forming the high resistance film 45 in the separation groove 18 between the adjacent photoelectric conversion cells 4 near the edge of the substrate 3, it is formed in the groove portion where the outside air moisture enters the photoelectric conversion layer region inside this. Therefore, it is possible to contribute to improving the reliability of the solar cell panel.

The first to seventh embodiments have been described above. These embodiments and examples are not independent of each other, and can be used in combination within a consistent range.
In the embodiment, the glass substrate 3 / the transparent electrode layer 41 / the photoelectric conversion layer 42 / the back electrode layer 43 is configured in this order, and the solar light is incident from the glass substrate 3 side. Even if the back electrode layer 43 / photoelectric conversion layer 42 / transparent electrode layer 41 are formed in this order, and sunlight is incident from the transparent electrode layer 41 side, the same effect can be obtained.

  In the first to sixth embodiments, the case where the bypass portion 8 is provided in the transparent electrode layer dividing groove 7 has been described. However, in the step of forming the back electrode layer, laser etching for dividing the adjacent photoelectric conversion cells 4 may be performed in the same manner as in the step of forming the transparent electrode layer. Therefore, the bypass portion 8 provided in the transparent electrode layer dividing groove 7 in the first to sixth embodiments may be provided in the back electrode layer dividing groove 18. In this case, in the step of laser etching the back electrode layer, the device described in the first to sixth embodiments (device in the step of laser etching the transparent electrode layer) can be applied. In this way, the same effect as described in the above-described embodiment can also be achieved by connecting the back electrode layers of the adjacent photoelectric conversion cells 4 by the bypass unit 8.

It is a top view of a photoelectric conversion module. It is sectional drawing of a photoelectric conversion module. It is explanatory drawing which shows the shape of the transparent electrode layer in the photoelectric conversion module of 1st Embodiment. It is explanatory drawing for demonstrating how to obtain | require the width | variety and space | interval of a bypass part. It is a flowchart which shows the manufacturing method of the photoelectric conversion module of 1st Embodiment. It is explanatory drawing for demonstrating the patterning of a transparent electrode layer in 1st Embodiment. It is explanatory drawing for demonstrating a hot spot generation | occurrence | production test. It is a schematic sectional drawing which shows the structure of the photoelectric conversion module in an Example. It is process sectional drawing which shows the manufacturing method of the solar cell panel in an Example. It is process sectional drawing which shows the manufacturing method of the solar cell panel in an Example. It is process sectional drawing which shows the manufacturing method of the solar cell panel in an Example. It is process sectional drawing which shows the manufacturing method of the solar cell panel in an Example. It is explanatory drawing for demonstrating the patterning of the transparent electrode layer in 2nd Embodiment. It is explanatory drawing for demonstrating the patterning of the transparent electrode layer in 3rd Embodiment. It is explanatory drawing for demonstrating the structure of the bypass part in 3rd Embodiment. It is explanatory drawing for demonstrating the structure of the transparent electrode layer in 4th Embodiment. It is explanatory drawing for demonstrating formation of the bypass part in 5th Embodiment. It is explanatory drawing for demonstrating formation of the bypass part in 5th Embodiment. It is explanatory drawing for demonstrating formation of a bypass part in the back surface electrode layer in 7th Embodiment. It is explanatory drawing for demonstrating formation of a bypass part in the back surface electrode layer in 7th Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Photoelectric conversion module 2 Surrounding area | region 3 Translucent board | substrate 4 Photoelectric conversion cell 41 Transparent electrode layer 42 Photoelectric conversion layer 43 Back surface electrode layer 45 High resistance film 5 Insulation groove | channel 6 Electric power generation area | region 7 Transparent electrode layer separation groove | channel 8 Bypass part 9 X- Y table 10 Mask 11 Mask 12 Etching laser beam 13 Oscillator 14 Shutter 15 Shutter control device 16 Drive device 17 Groove 18 Groove 19 Back sheet 20 Terminal box 21 Laser control device 50 Solar cell panel

Claims (19)

A plurality of photoelectric conversion cells arranged on a substrate;
A bypass section;
Comprising
Each of the plurality of photoelectric conversion cells is
A photoelectric conversion layer that receives light and converts it into electric power;
A transparent electrode layer provided on the light incident surface side so as to sandwich the photoelectric conversion layer, and a back electrode layer provided on the opposite side of the light incident surface,
The transparent electrode layer and the back electrode layer are each divided corresponding to the plurality of photoelectric conversion cells by dividing grooves,
The back electrode layer is a photoelectric conversion device connected to the transparent electrode layer of each adjacent photoelectric conversion cell so that the plurality of photoelectric conversion cells are electrically connected in series,
The bypass section is provided so as to fill at least a part of the dividing groove so as to connect the transparent electrode layers or the back electrode layers of the adjacent photoelectric conversion cells. Conversion device. The photoelectric conversion device according to claim 1,
The bypass part is adjacent to the transparent electrode layer without forming a separation groove of the transparent electrode layer or a separation groove of the back electrode layer formed when the photoelectric conversion cells are electrically connected in series. The photoelectric conversion device, wherein the transparent electrode layers or the back electrode layers of the two photoelectric conversion cells are connected so as to be electrically connected. The photoelectric conversion device according to claim 2,
An electrical resistance value of the bypass section between two adjacent photoelectric conversion cells is smaller than an electrical resistance value with respect to a reverse voltage in a dark state of each photoelectric conversion cell. The photoelectric conversion device according to claim 3,
Between the photoelectric conversion cells adjacent to each other, the length in the longitudinal direction of the photoelectric conversion cell obtained by totaling the portions provided with the bypass portion is the length of the photoelectric conversion cell obtained by adding up the portions not provided with the bypass portion. A photoelectric conversion device characterized by being smaller than the length in the direction. The photoelectric conversion device according to claim 4,
Each of the plurality of photoelectric conversion cells is formed in a strip shape,
The position of the bypass portion provided in the separation groove between the photoelectric conversion cells is the position of the bypass portion provided in the separation groove between the adjacent photoelectric conversion cells and the longitudinal direction of each photoelectric conversion cell. A photoelectric conversion device characterized by being different. A photoelectric conversion device according to claim 1,
The bypass unit is a photoelectric conversion device in which the transparent electrode layer is a part where a separation groove of the transparent electrode layer is not formed so as to be connected at a part between adjacent photoelectric conversion cells. A photoelectric conversion device according to any one of claims 1 to 6,
The transparent electrode layer is formed so that the separation groove of the transparent electrode layer has a plurality of dots at the boundary between the adjacent photoelectric conversion cells,
The said bypass part is a part with which the said transparent electrode layer remains between the said adjacent dots, The photoelectric conversion apparatus characterized by the above-mentioned. A photoelectric conversion device according to any one of claims 1 to 6,
The bypass unit is formed of a metal film provided in a separation groove of the transparent electrode layer. A photoelectric conversion device according to claim 1,
The bypass unit is provided in a separation groove of the back electrode layer, and is formed of a high resistance film having higher resistance than the back electrode layer. A method of manufacturing a photoelectric conversion device in which a plurality of photoelectric conversion cells are electrically connected in series,
A transparent electrode layer forming step of forming a transparent electrode layer;
A photoelectric conversion layer forming step of forming a photoelectric conversion layer that receives light and converts it into electric power;
A back electrode layer forming step of forming a back electrode layer;
Comprising
The transparent electrode layer forming step includes
Forming a film of the transparent electrode layer;
A patterning step of patterning the transparent electrode layer so that the formed transparent electrode layer is divided corresponding to each of the plurality of photoelectric conversion cells by a dividing groove; Patterning is performed so that a bypass part that connects the transparent electrode layers of the photoelectric conversion cells to be formed is formed. A method of manufacturing a photoelectric conversion device in which a plurality of photoelectric conversion cells are electrically connected in series,
A transparent electrode layer forming step of forming a transparent electrode layer;
A photoelectric conversion layer forming step of forming a photoelectric conversion layer that receives light and converts it into electric power;
A back electrode layer forming step of forming a back electrode layer;
Comprising
The back electrode layer forming step includes
Forming the back electrode layer; and
A patterning step of patterning the back electrode layer such that the formed back electrode layer is divided corresponding to each of the plurality of photoelectric conversion cells by a dividing groove; Patterning is performed so that a bypass portion that connects the back electrode layers is formed in a part between the photoelectric conversion cells. A method for manufacturing a photoelectric conversion device, comprising: It is a manufacturing method of the photoelectric conversion device according to claim 10 or 11,
In the patterning step, the length in the longitudinal direction of the photoelectric conversion cell in the portion where the bypass portion is provided between the adjacent photoelectric conversion cells is the length of the photoelectric conversion cell in the portion where the bypass portion is not provided. A method for manufacturing a photoelectric conversion device, wherein patterning is performed so that the length is smaller than a length in a direction. It is a manufacturing method of the photoelectric conversion device according to any one of claims 10 to 12,
In the said patterning process, patterning is performed by irradiating a laser, The manufacturing method of the photoelectric conversion apparatus characterized by the above-mentioned. It is a manufacturing method of the photoelectric conversion device according to claim 13,
The patterning step includes
Placing a mask in a region where the bypass portion is to be formed;
And a step of irradiating a laser after disposing the mask. It is a manufacturing method of the photoelectric conversion device according to claim 13,
In the patterning step, patterning is performed so that the bypass portion is formed by switching a shutter arranged on an optical path of a laser. It is a manufacturing method of the photoelectric conversion device according to claim 13,
A method for manufacturing a photoelectric conversion device, wherein irradiation is performed such that a laser beam is incident in a plurality of spaced apart dots when laser irradiation is performed in the patterning step. A method for manufacturing a photoelectric conversion device according to any one of claims 10 to 13,
The patterning step includes
A complete patterning step of patterning so that the objects to be patterned are completely separated between the adjacent photoelectric conversion cells;
A method of manufacturing a photoelectric conversion device, comprising: a metal paste arranging step of arranging a metal paste in an area where the bypass portion is to be formed after the complete patterning step. A method for manufacturing a photoelectric conversion device according to any one of claims 10 to 13,
The patterning step includes
A complete patterning step of patterning so that the objects to be patterned are completely separated between the adjacent photoelectric conversion cells;
A pulse that irradiates a laser near the separation groove of the patterning target in a region where the bypass portion is to be formed after the complete patterning step, and connects adjacent patterning targets with the residue of the patterning target An irradiation step. A method for manufacturing a photoelectric conversion device. A method of manufacturing a photoelectric conversion device in which a plurality of photoelectric conversion cells are electrically connected in series,
A transparent electrode layer forming step of forming a transparent electrode layer;
A photoelectric conversion layer forming step of forming a photoelectric conversion layer that receives light and converts it into electric power;
A back electrode layer forming step of forming a back electrode layer;
A bypass part forming step of forming a bypass part connecting the back electrode layers in a part between the adjacent photoelectric conversion cells;
Comprising
The back electrode layer forming step includes
Forming the back electrode layer; and
A patterning step of patterning the back electrode layer so that the formed back electrode layer is divided corresponding to each of the plurality of photoelectric conversion cells by dividing grooves, and the bypass portion forming step includes Performed after the patterning step;
In the bypass portion forming step, the bypass portion is formed by forming a high resistance film having a higher resistance than that of the back electrode layer so as to fill at least a part of the dividing groove. A method for manufacturing a conversion device.

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