JP2675428B2 - Method for manufacturing solar cell device - Google Patents

Description

TECHNICAL FIELD The present invention relates to an improvement in a method for manufacturing a solar cell device in which a solar cell is formed on the back surface of a substrate. (B) Conventional technology The development of solar cells for converting light energy into electrical energy for use is in progress. However, if this solar cell is used for household power, it is necessary to install solar cells over a wide range. There is an attempt to use roof tiles as this method. That is, the roof tile main body is formed of a material having a light-transmitting property and an insulating property, and a solar cell is formed on the back surface thereof. When the solar cell is formed by laser patterning, the roof tile main body is formed on the back surface. It is necessary to move this laser beam while the laser beam is focused. However, the roof tile main body is curved to prevent rainwater, and the processing accuracy of the roof tile main body is relatively low. Therefore, the roof tile main body does not fit within the shallow focus advance of the laser generator, so the focus is processed. Machining defects are likely to occur in the method of controlling the program according to the position. As a countermeasure against this, using a displacement measuring device that projects light from the laser beam generator onto the surface of the roof tile main body and captures this reflected light with a light receiver, the vertical distance between the issuer and light receiver and the roof tile main body is used. It is considered promising that the sensor in the photodetector detects the change in the horizontal direction as a horizontal position and the roof tile position is adjusted so that this distance always matches the focal length of the laser generator. However, when such a method is adopted, the conventional roof tile main body has a smooth back surface in order to reduce reflection loss, so that the light projected from the light emitting device of the displacement measuring device onto the roof tile main body is However, there is a problem that the curved portion may not be captured by the light receiver. 7 (a), (b), and (c) are schematic diagrams showing an optical system of a displacement side constant part for capturing the reflected light from the back surface of the roof tile main body and measuring the displacement thereof, and 1 in the figure. Light emitters 2 forming a displacement measurement unit, light receivers 3, and the back surface of the roof tile main body are shown. Now, the light emitted from the light emitter 1 is incident on the roof tile main body and partly transmitted, but the rest is reflected, and the vertical line at the incident point on the roof tile main body emits light as shown in FIG. 7 (a). When the light receiving unit 2 and the light receiving unit 2 coincide with the bisector of the optical axis, the light receiving unit 2 catches the light, but when they do not match, the reflected light is as shown in FIG. 7 (b) or (c). The light receiver 2 could not be reached, accurate distance adjustment could not be performed, and the distance was erroneously recognized, resulting in poor reliability. (C) Problem to be Solved by the Invention The present invention has been made in view of the above problems, and its object is to use a surface of a roof tile main body on which a solar cell is to be formed as a diffuse reflection surface of light. Form a diffused reflection surface of light on the back surface of the roof tile so that the receiver can accurately capture the reflected light from the roof tile main body and automatically adjust the focus and improve the processing accuracy. Is. (D) Means for Solving the Problems On the back surface side of the curved substrate having translucency and insulation,
When a plurality of solar cell elements are separated and arranged in parallel in a direction orthogonal to the bending direction, irradiation light is irradiated to the back surface of the sample and the displacement of the back surface of the substrate is measured. In the method for manufacturing a solar cell device in which the solar cell element is irradiated with an energy beam based on the above, the irregular surface is formed on the back surface of the substrate at a position irradiated with the irradiation light, and the irregular reflection is performed. The displacement of the back surface of the substrate is measured by receiving the irradiation light that is diffusely reflected by the surface. (E) Operation During laser patterning of a solar cell, when light is incident on the front surface of the substrate of the solar cell device, a diffused reflection surface is formed on the back surface at the location where the irradiation light is applied.
A part of the light emitted from the light emitting device of the displacement measuring device is diffusely reflected and is always accurately captured by the light receiving device. (F) Example FIG. 1 is a schematic view of the back surface of a solar cell device according to the present invention, in which 10 is a roof tile main body made of a translucent and insulating material such as glass, and 11 is a roof. Using the roof tile body 10 as a substrate,
The solar cell formed on the back surface is shown. Although not specifically shown, each solar cell 11 is configured by laminating a transparent electrode, an amorphous silicon layer, and a back electrode in this order, and the light transmitted through the roof tile main body 10 is the solar cell 11.
Electrons and holes generated by being incident on the amorphous silicon layer of each of the transparent electrodes, the back electrode, and further the transparent electrodes and the back electrodes of the other adjacent solar cells 11 are collected and superposed electrically. The added power is taken out. By the way, when the solar cell 11 as described above is formed by laser patterning, as shown in FIG. 2, the roof tile main body 10 is, as shown in FIG. Are formed. More specifically, on the entire back surface (or a part) of the roof tile main body 10, a large number of fine concaves and convexes are formed parallel to each other in a direction orthogonal to the curved direction of the roof tile main body 10 to form the solar cell 11. Roof tile body to be
Diffuse reflection surface 10a consisting of smooth uneven surface on the back side of 10a
It is formed in. The formation pitch of the concave and convex shapes is about several tens to 100 μm, and the shape is a combination of sine curve and other arcs, and the light from the light emitting device 1 in the displacement measuring device is shown in FIG. As shown, the roof tile main body 10 is irregularly reflected on the back surface, and at least a part of this reflected light can be reliably captured by the light receiver 2. For example, when the light emitting device 1 and the light receiving device 2 of the displacement measuring device are arranged at an angle symmetrical with respect to a vertical line to the surface of the roof tile main body 10, the concave shape and the convex shape at least partially form the horizontal plane 10c. It may be set to have it. Of course, this concave and convex forming pitch,
The shape is not particularly limited to the above, and the light projected from the light emitting device 1 of the roof tile main body 10 is reflected by the roof tile main body 10 and at least a part thereof is always captured by the light receiver 2. It may be of any type. However, it is desirable that the concave and convex back surfaces be as smooth as possible so that the sunlight that has entered the roof tile main body 10 will enter the solar cell 11 with the lowest possible reflectance. As a result, as shown in FIG. 5, the back surface of the roof tile main body 10 constructed in this way is diffusely reflected by the uneven surface formed on the back surface when light is incident as shown in FIG. When light is incident from the light emitting device 1 of the displacement measuring device, a part of the light is diffusely reflected and is always accurately captured by the light receiving device 2. FIG. 6 is a schematic diagram showing a mode in which laser patterning is applied in the process of forming a solar cell formed on the back surface of the roof tile main body 10 according to the present invention, and 21 is a moving table in the Z-axis direction, that is, in the vertical direction. , 22 is in the X-axis direction, that is, left,
A moving table to the right, 23 to the Y-axis direction, that is, a moving table in the front-rear direction, 24 to a laser generator, and 25 to a displacement measuring device. The roof tile main body 10 is placed on the moving table 21 with the back surface facing upward so that the amorphous silicon layer formed on the transparent electrode on the back surface of the roof tile main body 10 is divided and formed for each part constituting each unit solar cell. ing. A displacement measuring device 25 faces the roof tile main body 10 on the moving table 21, and a laser generator 24 faces vertically downward to the center between the light emitting device 1 and the light receiving device 2 of the displacement measuring device 25, and They are arranged with their focal points aligned with the surface of the amorphous silicon layer on the roof tile body 10. 26 is a Z-axis direction drive control unit, 27
Is an X- and Y-axis direction drive control unit, and the locus of the laser beam for patterning the amorphous silicon layer on the back surface of the roof tile main body 10 is preset, and based on the laser patterning start signal, Table 2
Move 2 and 23, move the laser beam on the amorphous silicon layer of the roof tile main body 10 to the back side of the substrate,
The amorphous silicon layer is divided and formed in parallel with the direction orthogonal to the bending direction. On the other hand, from the light emitting device 1 of the displacement measuring device 25, the roof tile main body 10
The light is projected onto the amorphous silicon layer surface on the back surface of the light receiving device, the diffuse reflection is captured by the light receiving device 2 from the back surface, and a signal corresponding to a change in the light receiving position of the one-dimensional sensor of the light receiving device 2 is output.
Amplified by the amplifier 28, Z as the amount of change of the roof tile 10
It is input to the axial drive control unit 26. The Z-axis direction drive control unit 26 outputs a control signal to the moving table 21 and moves the moving table 21 in the vertical direction to solve the amount of change in the upper and lower directions of the roof tile main body 10 and moves the roof tile main body 10 in the vertical direction.
The point of incidence of the laser beam on the lens is always matched with the focal point of the lens of the laser generator 24. Although the above embodiment has been described with respect to the configuration for performing the laser patterning, it is needless to say that it can be applied to the case where a high energy beam such as an electron beam or an ion beam is used instead of the laser. It is also possible to apply it to the measurement of surface dimensions and properties of the main body. FIG. 8 is a schematic cross-sectional view showing another embodiment of the present invention. In this roof tile main body 10 ', a portion where a tangent line in the curved portion is horizontal, that is, a mountain top portion 10 of the curved portion.
The portion excluding d'and the valley bottom portion 10e 'is formed as diffuse reflection 10a'. This is because the reflected light at this portion can be captured within the field of view of the objective lens of the displacement measuring device 25 without forming an uneven surface, which also improves the transmittance of the roof tile main body 10 ', The effect is to reduce the reflection loss of. In the above-mentioned embodiment, the roof tile main body 10 'has a structure in which the irregular reflection surface is not formed on the peak portion and the valley bottom portion.However, the region where the irregular reflection surface is not formed is not limited to the above portion, and displacement measurement is performed. Needless to say, the unevenness may be small or not formed in the portion where the light from the light emitter 1 can be reliably captured by the light receiver 2 depending on the relative position of the light emitter 1 and the light receiver 2 of the device 25. (G) Effect of the Invention According to the present invention, on the back surface side of a curved substrate having a light-transmitting property and an insulating property, a plurality of solar cells are formed in a separated arrangement in parallel to a direction orthogonal to the bending direction, On the back surface of the substrate, a diffused light reflection surface is formed at a position where the light from the light emitter is irradiated, and the light diffusedly reflected by the diffused reflection surface is received by the light receiver. By doing so,
The receiver can reliably capture the reflected light of the light incident from the light emitter, recognize the displacement of the surface position of the roof tile main body, and it becomes possible to accurately position the processing beam focus on the roof tile main body surface, The present invention has excellent effects such that the roof tile main body can be easily processed even if its curved surface and molding tolerance are large, the roof tile main body can be easily manufactured, and the cost of the product can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view of a solar cell used in the present invention, FIG. 2 is a schematic cross-sectional view of a roof tile main body used in the present invention, and FIG. 3 is a roof tile of FIG. Partial enlarged view of the main body, FIG. 4 is a further enlarged partial enlarged view, FIG. 5 is a relationship diagram between the roof tile main body and the displacement measuring device in the present invention, and FIG. 6 is a schematic view showing a mode of laser patterning, 7 (a), (b) and (c) are relationship diagrams of a conventional roof tile main body and its rear surface displacement detection amount, and FIG. 8 is a schematic sectional view showing another embodiment of the present invention. . 1 ... Light emitter, 2 ... Light receiver, 10, 10 '... Roof tile main body, 11 ... Solar cell, 21, 22, 23 ... Moving table, 24
...... Laser generator, 25 …… Displacement measuring device.

Claims (1)

(57) [Claims] On the back surface side of the curved substrate having a light-transmitting property and an insulating property, a plurality of solar cell elements are separated and arranged in parallel to the direction orthogonal to the bending direction, and irradiation light is applied to the back surface of the substrate. While irradiating and measuring the displacement of the back surface of the substrate, the solar cell element is irradiated with an energy beam based on the measured value, in the method for manufacturing a solar cell device for separating the element, the back surface of the substrate, A method for manufacturing a solar cell device, comprising: forming a diffused reflection surface at a position irradiated with irradiation light, and measuring the displacement of the back surface of the substrate by receiving the irradiation light diffusely reflected by the reflection surface.