KR20110012955A - Method of inspecting a solar cell module and method of manufacturing the solar cell module by using the same - Google Patents

Abstract

PURPOSE: A solar battery cell module repair method and a manufacturing method using the same are provided to improve the productivity by reducing the process steps by selectively implementing the laser scribing process only on a cell determined to be defective. CONSTITUTION: A PIN film and a back electrode are formed on a front electrode(S100). The cell unit is distinguished by forming the grooves exposing the front electrode with the laser scribing process on the PIN film and the back electrode(S200). A groove having the defect is selected by determining whether the groove is defective(S300).

Description

Method of inspecting a solar cell module and Method of manufacturing the solar cell module by using the same}

The present invention relates to a method for repairing a solar cell module and a method for manufacturing a solar cell module using the same. More specifically, the present invention relates to a method for repairing a solar cell module for converting sunlight into electrical energy and a method for manufacturing a solar cell module using the same.

Recently, as the prediction of depletion of existing energy sources such as oil and coal is increasing, interest in alternative energy to replace them is increasing. Among them, solar energy is particularly attracting attention because of its abundant energy resources and no problems with environmental pollution.

There are two methods of using solar energy: solar energy, which generates steam required to rotate a turbine using solar heat, and solar energy, which converts photons into electrical energy using the properties of semiconductors. Solar energy generally refers to solar cells (hereinafter, referred to as "solar cells"). Various studies are being conducted on such solar cells as future energy means.

As described above, the matters described in the "Background art" are intended to help the understanding of the background of the present invention, and the technology described in this part is not necessarily the prior art, and is not known in the art, such as the technology falling within the protection scope of the present invention. Can be.

One embodiment of the present invention provides a repair method of a solar cell module.

Other embodiments of the present invention provide a solar cell manufacturing method using the repair method.

According to one embodiment of the present invention, a solar cell module repair method is provided. Specifically, a PIN film and a rear electrode are formed on the front electrode. Cells are divided by forming grooves on the PIN layer and the rear electrode to expose the front electrode by a laser scribing process. Subsequently, it is determined whether the grooves are defective and the one having the defect is selected. Thereafter, only the cells containing the defective grooves are formed in the PIN film and the rear electrode spaced apart from the defective grooves.

In order to determine whether the groove is defective, resistance may be measured by installing a probe on each of the grooves located at both sides of the groove. Determining whether the groove is defective may be performed in units of cells. In more detail, when the resistance is measured lower than the neighboring cells, it may be determined as defective. Here, the value of the resistance lower than the peripheral cell may be several KΩ or less. The auxiliary groove may be formed through a laser scribing process. The laser scribing process uses a laser of 532 nm wavelength, the auxiliary groove may be 0.0001 to 1mm away from the groove.

According to another embodiment of the present invention, a method of manufacturing a solar cell is provided. Specifically, the front electrode is formed on the transparent substrate. Subsequently, a first laser scribing process is performed on the front electrode to form a first groove on the front electrode, thereby separating the front electrode in units of cells. And a PIN film is formed so that a 1st groove may be embedded on a front electrode. Subsequently, a second laser scribing process is performed on the PIN film to form a second groove spaced in the predetermined direction from the first groove in the PIN film. And a back electrode is formed so that a 2nd groove may be embedded on a PIN film. Subsequently, a third laser scribing process is performed on the back electrode and the PIN film to form a third groove spaced in the direction from the second groove in the back electrode and the PIN film. Subsequently, the resistance between the parts located on both sides of the third groove among the rear electrodes is measured to determine whether the third groove is defective.

The first laser scribing process may be provided on the transparent substrate side to pass through the transparent substrate to be incident on the front electrode. The first laser scribing process may be provided on the opposite side of the transparent substrate and incident on the front electrode.

Materials included in the front electrode include zinc oxide (ZnO), indium gallium zinc oxide (IGZO), indium tin oxide (ITO), silicon carbide (n-doped SIC) doped with N-type impurities, silicon oxide (SiO ₂ ), or Nitrogen oxide (SiNx). These may be used alone or in combination.

The PIN film can be laminated once or twice and three times. The PIN film may include a P layer including amorphous silicon doped with P-type impurities, an I layer including intrinsic amorphous silicon, and an N layer including amorphous silicon doped with N-type impurities.

 The material used for the I layer is, for example, amorphous silicon (a-Si), micro-crystal Si, microcrystalline silicon germanium (a-SiGe), micro-crystal SiGe or amorphous silicon. Carbide (a-SiC). These may be used alone or in combination.

The second laser scribing process may use a laser in the wavelength range of about 500nm to about 600nm provided on the transparent substrate side. The wavelength band may be about 532 nm.

The third laser scribing process is provided on the transparent substrate side and a laser in the wavelength range of about 500 nm to about 600 nm may be used. The wavelength band may be about 532 nm.

If it is determined that the third groove is defective, the fragment of the rear electrode generated in the third laser scribing process may be connected to the front electrode through the third groove. In contrast, when the third groove is judged to be defective, the depth of the third groove is lower than the height measured from the upper surface of the front electrode to the upper surface of the rear electrode, and the rear surface generated in the third laser scribing process inside the third groove. It may be the case that the fragments of the electrode remain so that the rear electrode is not cut by the third groove.

The determining of whether the third groove is defective may be to measure resistance by installing probes on portions positioned at both sides of the third group. The determining of whether the third groove is defective may be performed in units of cells.

If the resistance is measured lower than the surrounding cells it can be determined that the failure. The value of the resistance lower than the peripheral cell can be several KΩ or less. The method may further include forming a fourth groove spaced apart in the direction from the third groove.

The forming of the fourth groove may be performed through a fourth laser scribing process, and the fourth laser scribing process may be performed only in a cell including a defective one of the third grooves. The fourth laser scribing process is provided on the transparent substrate side and lasers in the wavelength range of about 500 nm to about 600 nm may be used. The fourth laser scribing process uses a laser having a wavelength of about 532 nm, and the fourth groove may be about 0.0001 to about 1 mm away from the third groove.

The material used for the front electrode may be at least one selected from the group consisting of zinc oxide, indium gallium zinc oxide, indium tin oxide, silicon carbide doped with N-type impurities, silicon oxide, and nitrogen oxide.

According to the present invention, a laser scavenging process may be added as a repair process to prevent an effective short circuit between cells. In addition, since the laser scribing process for repairing is selectively performed only on the cells determined as defective cells, process steps can be reduced and production yield can be improved.

Hereinafter, a solar cell module repair method and a manufacturing method of a solar cell module using the same will be described with reference to the accompanying drawings. I) The shape, size, ratio, angle, number, operation, and the like shown in the accompanying drawings may be changed to be rough. ii) Since the drawings are shown with the eyes of the observer, the direction or position for describing the drawings may be variously changed according to the positions of the observers. iii) The same reference numerals may be used for the same parts even if the reference numbers are different. iv) When 'include', 'have', 'consist', etc. are used, other parts may be added unless 'only' is used. v) When described in the singular, the plural can also be interpreted. vi) Even if numerical values, shapes, sizes comparisons, positional relations, etc. are not described as 'about' or 'substantial', they are interpreted to include a normal error range. vii) The terms 'after', 'before', 'following', 'and', 'here', and 'following' are not used to limit the temporal position. viii) The terms 'first', 'second', etc. are merely used selectively, interchangeably or repeatedly, for convenience of distinction and are not to be interpreted in a limiting sense. ix) If the positional relationship between two parts is described as 'upper', 'upper', 'lower' or 'next', etc., one or more Other parts may be interposed. x) When parts are connected by '~', they are interpreted to include not only parts but also combinations, but only when parts are connected by 'or'.

1 is a flowchart illustrating a repair method of a solar cell module according to an embodiment of the present invention.

Referring to FIG. 1, a PIN film and a rear electrode are formed on the front electrode (S100).

Subsequently, grooves are formed on the PIN layer and the rear electrode to expose the front electrode by a laser scribing process, thereby distinguishing the cell units (S200). The grooves have a shape extending in one direction and the grooves expose the front electrode.

The grooves formed here may have a number of defects. For example, even if a groove is formed, a back electrode between cells is connected or a back electrode is connected to a front electrode.

Therefore, it is determined whether the grooves are defective by selecting the one having a defect (S300). In order to determine whether the groove is defective, a method of measuring resistance by installing a probe on each of the rear electrode portions positioned at both sides of the groove may be adopted. The step of determining whether the groove is defective may be performed in units of cells. In more detail, whether all the cells are defective may be determined. However, only a predetermined selected cell may determine whether the groove is defective.

In this case, when the resistance is measured lower than the peripheral cells, it may be determined that the electrical short is generated between the rear electrodes or between the rear electrodes and the front electrodes. For example, the value of the resistance lower than the peripheral cell may be several KΩ or less.

Subsequently, only a cell including a defective groove is formed with an auxiliary groove spaced apart from the defective groove on the PIN film and the rear electrode (S400). Electrical insulation between the back electrode or between the back electrode and the front electrode which could not be achieved by a defective groove can be realized by forming an auxiliary groove.

In this case, the auxiliary groove may be performed through a laser scribing process. For example, the laser scribing process uses a laser having a wavelength of about 532 nm, and the auxiliary groove in the unit cell may be formed to be spaced from about 0.0001 to about 1 mm from the groove.

2 to 12 are views showing a method of manufacturing a solar cell module according to an embodiment of the present invention.

Referring to FIG. 2, a transparent substrate 100 is prepared. The transparent substrate 100 may include a glass material. Next, the front electrode 110 is formed on the transparent substrate 100. The front electrode 110 may be formed on the transparent substrate 100 by a physical vapor deposition (PVD) method such as chemical vapor deposition (CVD) or sputtering, but is not limited thereto. It is not.

The front electrode 110 may include a transparent conductive oxide (TCO). Examples of transparent conductive oxides include tin oxide (SnO 2), zinc aluminum oxide (ZAO), indium gallium zinc oxide (IGZO), indium tin oxide (ITO), silicon carbide doped with N-type impurities (n-doped SIC), and oxidation Silicon (SiO ₂ ), nitrogen oxides (SiNx) may be, but are not limited thereto.

Referring to FIG. 3, a first laser scribing process is performed on the front electrode 110. The first laser scribing process may be provided on the transparent substrate 100 to pass through the transparent substrate 100 to enter the front electrode 110, but may be provided on the opposite side of the transparent substrate 100.

First grooves G1 extending in one direction are formed in the front electrode 110 by a first laser scribing process. The first grooves G1 may extend in parallel to each other and the front electrode 110 is exposed at the bottom thereof. The front electrodes 110 are divided into cell regions by two adjacent first grooves G1.

Referring to FIG. 4, a PIN layer 120 is formed on the transparent substrate 100 and the front electrode 110 to fill the first groove G1. The PIN film 120 may be formed using a chemical vapor deposition method such as plasma enhanced chemical vapor deposition (PECVD), but is not limited thereto.

The PIN film 120 includes a P layer containing amorphous silicon doped with P-type impurities, an I layer containing intrinsic amorphous silicon, and an amorphous silicon doped with N-type impurities. It may have an N layer comprising a. When sunlight is applied to the PIN film 120, a potential difference occurs between the P layer and the Nth layer so that a current flows from the P layer to the N layer through the I layer.

The PIN film 120 may be changed in various ways. The PIN film 120 may be stacked twice or three times. And the material used for the I layer is, for example, amorphous silicon (a-Si), micro-crystal Si (micro-crystal Si), amorphous silicon germanium (a-SiGe), micro-crystal silicon germanium (micro-crystal SiGe) or amorphous Silicon carbide (a-SiC). These may be used alone or in combination.

Referring to FIG. 5, a second laser scribing process is performed on the PIN film 120. In this case, the second laser scribing process is provided on the transparent substrate 100 side, and a laser in a wavelength band of about 500 nm to about 600 nm may be used. Preferably a laser of about 532 nm wavelength can be used.

A second groove G2 is formed in the PIN film 120 by the second laser scribing process. The second groove G2 is located tens of micrometers away from the first groove G1. For example, as shown in FIG. 5, the second groove G2 may extend substantially parallel to the first groove G1 at the right side of the first groove G1. The front electrode 110 is exposed on the bottom surface of the second groove G2.

Referring to FIG. 6, a rear electrode 130 filling the second groove G2 is formed on the PIN layer 120 and the front electrode 110. The back electrode 130 may be formed by a physical vapor deposition method such as chemical vapor deposition or sputtering, but is not limited thereto.

Referring to FIG. 7, a third laser scribing process is performed on the back electrode 130 and the PIN film 120. Here, the third laser scribing process is provided on the transparent substrate 100 side, and a laser in a wavelength band of about 500 nm to about 600 nm may be used. Preferably a laser of about 532 nm wavelength can be used.

A third groove G3 is formed on the back electrode 130 and the PIN film 120 by a third laser scribing process. The third groove G3 is located tens of micrometers away from the second groove G2. For example, as shown in FIG. 7, the third groove G3 may extend substantially parallel to the second groove G2 at the right side of the second groove G2.

Normal operation of the solar cell module is possible only when the rear electrode 130 is not left inside the third groove G3. If the fragment of the rear electrode 130 is connected to the front electrode 110 as shown in part "A" of FIG. 7 and FIG. 8, the electrical short between the rear electrode 130 and the front electrode 110 ( short) occurs and becomes a defective cell. This reduces the total current and total voltage of the cells in series.

In detail, when the third groove G3 is determined to be defective as shown in FIGS. 7 and 8, fragments of the rear electrode 130 generated in the third laser scribing process are removed from the front electrode 110 by electrostatic attraction. It is a case of sticking through 3 grooves (G3).

9 is a view showing the shape of another defective cell. In detail, the defective cell is illustrated in part “A” of FIG. 9, and a photograph photographing the defective cell is illustrated in FIG. 10. Referring to part “A” of FIG. 9 and FIG. 10, in the process of performing the third laser scribing process, when the intensity of the wavelength decreases due to the overlapping of the wavelength, the PIN film is disposed below the third groove G3. There is a case where 120 remains.

In detail, the defect of the third groove G3 illustrated in FIGS. 9 and 10 may include the height (D1) of the third groove G3 measured from the upper surface of the front electrode 110 to the upper surface of the rear electrode 130. Lower than H), fragments of the rear electrode 130 generated in the third laser scribing process remain inside the third groove G3, and the rear electrode 130 is cut by the third groove G3. If not.

In this case, since the width of the third groove G3 is narrowed or the height is lowered, the rear electrode 130 is not completely separated in units of cells by the third groove G3, thereby causing a short circuit between cells. In this case, the total current and the total voltage of the cells connected in series are reduced.

Referring to FIG. 11, an inspection process is performed for each cell to determine such defective cells. In detail, the probes 1a and 1b are installed at portions positioned at both sides of the third groove G3 of the rear electrode 130. Then, the resistance is measured through the probes 1a and 1b.

When the resistance is measured to be lower than the peripheral probes 1a and 1b as a result of the resistance measurement, it is classified as a defective cell because an electrical short circuit occurs. This resistance measurement can be performed per cell. In this case, the resistance regarded as a defective cell may be a case of about several KΩ or less.

Referring to FIG. 12, a fourth laser scribing process is selectively performed on the defective cells in which the third grooves G3 shown in regions “A” of FIGS. 7 and 9 are formed. Herein, the fourth laser scribing process is performed only on the defective cells, not on all the cells.

The fourth laser scribing process is provided on the transparent substrate 100 side, and a laser in the wavelength band of about 500 nm to about 600 nm may be used. Preferably a laser of about 532 nm wavelength can be used.

A fourth groove G4 is formed on the PIN layer 120 and the rear electrode 130 by a fourth laser scribing process. The fourth groove G4 may communicate with the third groove G3. Alternatively, the fourth groove G4 may be spaced apart from about 0.0001 to about 1 mm from the third groove G3.

For example, as illustrated in FIG. 12, the fourth groove G4 may extend substantially parallel to the third groove G3 at the right side of the third groove G3. Even when the fourth groove is formed, the probability of becoming a defective cell is extremely small.

However, according to an embodiment of the present invention, if the defect is not cured even after performing the resistance measurement described in FIG. 11 again on the defective cell in which the fourth groove G4 is formed, the fourth laser scribe described in FIG. 12. The process of performing the ice process again may be repeated.

As mentioned above, although embodiments of the present invention have been described, the examples are merely examples for describing the protection scope of the present invention described in the claims and do not limit the protection scope of the present invention. In addition, the protection scope of the present invention can be extended to the technically equivalent range of the claims.

1 is a flowchart illustrating a repair method of a solar cell module according to an embodiment of the present invention.

2 to 12 are views showing a method of manufacturing a solar cell module according to an embodiment of the present invention.

Claims (20)

Selecting a defective one of the grooves formed to expose the front electrode on the PIN film and the back electrode in order to distinguish the solar cells including the sequentially stacked front electrode, the PIN film, and the back electrode by cell unit; ; And Forming an auxiliary groove in the PIN layer and the rear electrode spaced apart from the groove having the defect only in a cell including the groove having the defect. The solar cell module repair method of claim 1, wherein the selecting of the grooves having defects comprises measuring a resistance by installing probes on portions positioned at both sides of the groove. The method of claim 1, wherein the selecting of the grooves with defects is performed on a cell basis. The solar cell repair method of claim 1, wherein the resistance of the solar cell module is determined to be defective when the resistance is measured to be lower than a peripheral cell. The method of claim 4, wherein a value of the resistance lower than a peripheral cell is several K Ω or less. The method of claim 1, wherein the forming of the auxiliary groove is performed through a laser scribing process. The method of claim 6, wherein the laser scribing process uses a laser having a wavelength of 532 nm, and the auxiliary groove is 0.0001 to 1 mm away from the groove. Forming a front electrode on the transparent substrate; Performing a first laser scribing process on the front electrode to form a first groove on the front electrode to separate the front electrode into cells; Forming a PIN film to fill a first groove on the front electrode; Performing a second laser scribing process on the PIN film to form a second groove on the PIN film spaced apart from the first groove in a predetermined direction; Forming a rear electrode on the PIN layer to fill the second groove; Performing a third laser scribing process on the back electrode and the PIN film to form the third groove spaced in a direction from the second groove on the back electrode and the PIN film; And And measuring resistance between portions of the rear electrode positioned at both sides of the third groove to determine whether the third groove is defective. The method of claim 8, wherein the second laser scribing process uses a laser having a wavelength band of 500 nm to 600 nm provided from the transparent substrate side. The method of claim 8, wherein the third laser scribing process is provided on the transparent substrate side, and a laser in a wavelength band of 500 to 600 nm is used. The solar cell of claim 8, wherein when the third groove is determined to be defective, a fragment of the rear electrode generated in the third laser scribing process is connected to the front electrode through the third groove. Method of manufacturing the module. The method of claim 8, wherein when the third groove is determined to be defective, a depth of the third groove is lower than a height measured from an upper surface of the front electrode to an upper surface of the rear electrode. The method of manufacturing a solar cell module when the debris of the back electrode generated in the third laser scribing process remains inside the third groove so that the back electrode is not cut by the third groove. The method of claim 8, wherein the determining of whether the third groove is defective is performed by measuring a resistance by installing probes on portions positioned at both sides of the third group. The method of claim 13, wherein the determining of whether the third groove is defective is performed on a cell basis. The method of claim 13, wherein the resistance is determined to be defective when the resistance is measured to be lower than a peripheral cell. The method of manufacturing a solar cell module according to claim 15, wherein the value of the resistance lower than a peripheral cell is several KΩ or less. The method of claim 8, further comprising forming a fourth groove spaced in a direction from that determined as a failure among the third grooves. 18. The cell of claim 17, wherein the forming of the fourth groove is performed through a fourth laser scribing process, and the fourth laser scribing process includes a cell determined to be defective among the third grooves. Method for manufacturing a solar cell module performed only. 19. The method of claim 18, wherein the fourth laser scribing process is provided on the transparent substrate side and a laser in a wavelength band of 500 to 600 nm is used. The method of claim 19, wherein the fourth laser scribing process uses a laser having a wavelength of 532 nm, and the fourth groove is 0.0001 to 1 mm away from the third groove.

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