WO2023015936A1

WO2023015936A1 - Method and apparatus for laser edge trimming for solar cell

Info

Publication number: WO2023015936A1
Application number: PCT/CN2022/088110
Authority: WO
Inventors: 汪玉树; 胡莹
Original assignee: 苏州迈为科技股份有限公司
Priority date: 2021-08-13
Filing date: 2022-04-21
Publication date: 2023-02-16
Also published as: CN113649701B; CN113649701A

Abstract

A method and apparatus for laser edge trimming for solar cells, comprising the steps: executing a first irradiation operation, performing scribing and segmentation of a thin-film layer of a battery along a preset contour direction using a first laser, and dividing the thin-film layer into an active region and an inactive region; executing a second irradiation operation and removing the thin-film layer in the inactive region using a second laser. Also disclosed is an apparatus implementing the described method. When using the described method and apparatus for edge trimming, the first irradiation operation is performed first, then the second irradiation operation is performed, effectively reducing edge thermal influence on a solar cell in an edge trimming process. Furthermore, the production costs can also be reduced, and edge trimming efficiency and edge trimming quality can be increased.

Description

Laser edge cleaning method and device for solar cells

technical field

The invention belongs to the technical field of solar cells, and in particular relates to a laser edge-clearing method and device for solar cells.

Background technique

A solar cell is usually composed of a glass substrate and a thin-film layer structure attached to the glass substrate. For example, Figure 1 is a schematic diagram of the structure of a perovskite solar cell. The thin-film layer on the glass substrate includes a transparent conductive layer from the bottom up, perovskite Mineral layer (or film layer of other materials), conductive layer. In the production process of solar cells, edge cleaning is carried out along the edge of the glass substrate. In the existing production process, high-power, large-spot, and low-frequency infrared lasers are often used for edge cleaning to remove the edges of the film layer to be removed. When clearing the edges of large-area products, most of them use splicing and scanning to carry out the edge clearing process. As shown in Figure 2, the edge of the scanned small unit area is first cleared, and then the next small unit is scanned and cleared. A combination of small units is spliced into an area that needs to be cleared.

However, using the above-mentioned method, due to the high-energy laser used, the edge-cleaned product will have a larger edge heat-affected zone, as shown in Figure 3, which will affect the power generation efficiency of the solar cell; When cleaning the edges of noodle products, when the squares are spliced and scanned, splicing marks will be generated and the efficiency of edge cleaning will be affected.

In addition, in the prior art, some edge cleaning processes are also provided. For example, the invention patent application with application number 201110205023.2 discloses a multi-pass laser edge removal process for thin-film solar modules. In this invention patent application, through Electromagnetic radiation of one power level removes all layers except the first conductive layer in the thin film layer of the edge region, and then uses electromagnetic radiation of a second power level to remove the edge region of the first conductive layer.

For another example, the invention patent application with application number 202010361352.5 discloses a film removal method, which includes a first irradiation operation, which is used to irradiate the plurality of unit pulse laser beams to the substrate while the substrate is rotating. the substrate; and a second irradiation operation for irradiating the plurality of unit pulse laser beams to a region of the substrate that is not irradiated with the unit pulse laser beams in the first irradiation operation. However, in this patent application, two irradiation operations are performed. In the case of substrate rotation, the area to be treated is irradiated with multiple pulsed lasers for the first time, and the unirradiated area of the area to be treated is irradiated for the second time, so that finally Clean up the area to be treated. The essence of this method is that it cannot be cleaned up in the first irradiation operation, and then another irradiation operation is performed.

For another example, the invention patent application with the application number 201811625492.8 discloses a laser edge cleaning method for solar cells. The technical solution of this patent application includes firstly letting the laser light of the first wavelength pass through the substrate to remove the photoelectric conversion layer and the edge to be removed of the back electrode; then making the laser light of the second wavelength pass through the substrate to remove the The edge to be removed of the front electrode. In this patent application, only a part of the film layer is removed in each process.

However, in the technical solutions described in the above-mentioned patent application documents, the problem of how to reduce the thermal influence of the edge generated in the edge-cleaning process is seldom considered. Therefore, when the above-mentioned technical solution is used to clear the edge of the solar cell, there will still be a large edge thermal impact on the solar cell.

Contents of the invention

Technical problem: Aiming at the problem that the existing technology has a large edge heat effect when clearing solar energy, a laser edge clearing method for solar cells and a device for realizing the method are provided. Utilizing the present invention can improve processing efficiency while reducing edge thermal influence, avoid splicing traces in the prior art, and reduce cost.

Technical solution: On the one hand, the present invention provides a laser edge cleaning method for solar cells, including:

Executing the first irradiation operation, using the first laser to scribe and divide the thin film layer of the battery along the preset contour direction, and divide the thin film layer into an effective area and an invalid area;

A second irradiation operation is performed, using a second laser, to remove the thin film layer in the inactive area.

In the implementation process, the effective area and the invalid area are first divided by the first irradiation operation, and then the invalid area is cleared by the second irradiation operation, then in the process of clearing the invalid area, it will not cause serious damage to the effective area. Even if the power of the second laser is greater, it will only ablate the thin film layer in the invalid area, so it will not affect the effective area, so the edge heat affected area of the product is small, thus ensuring the solar cell conductivity.

Further, after the first irradiation operation is completed, the second irradiation operation is performed.

Further, the power of the first laser is smaller than the power of the second laser.

Further, the use power range of the first laser is 1W-30W, and the use power range of the second laser is 100W-500W.

In the implementation process, the first irradiation operation is completed by using the first laser, which can effectively reduce the thermal impact on the effective area, and because the first irradiation operation is only for area division, therefore, while reducing the thermal impact, it also takes into account The efficiency is improved, and the cost can be reduced by using a lower power laser.

Further, the wavelength bands of the first laser and the second laser are both in the range of 300nm-2000nm. In a preferred embodiment of the present invention, the selected first laser and the second laser are both in the wavelength range of 1064nm.

Further, in one embodiment, when the first irradiation operation is performed, the first laser light is directly irradiated on the thin film layer; when the second irradiation operation is performed, the second laser light is irradiated on the thin film layer through the glass substrate of the battery.

Further, in another embodiment, when the first irradiation operation is performed, the first laser light is directly irradiated on the film layer; when the second irradiation operation is performed, the second laser light is directly irradiated on the film layer.

Further, in another embodiment, when the first irradiation operation is performed, the first laser light is irradiated on the film layer through the glass substrate; when the second irradiation operation is performed, the second laser light is irradiated on the film layer through the glass substrate .

Further, in another embodiment, when the first irradiation operation is performed, the first laser light is irradiated on the film layer through the glass substrate; when the second irradiation operation is performed, the second laser light is directly irradiated on the film layer.

Through the above several implementation forms, the structural form of the laser edge cleaning equipment can be flexibly designed according to the requirements, so as to facilitate the implementation of the edge cleaning process.

Further, when performing the first irradiation operation, the first laser is used to scribe multiple times along the predetermined contour direction on the film layer, and the multiple scribed lines are superimposed to form a scribed area with a certain width along the normal direction of the preset contour direction, so The scribed area divides the film layer into an active area and an inactive area. The invalid area and the effective area are fully separated to avoid a large thermal impact on the effective area when the invalid area is cleaned.

Further, when the first laser is used to scribe the film layer multiple times along the preset contour direction, after one scribing is completed, the first laser moves one unit along the normal direction of the preset contour direction for the next scribing Lines drawn twice adjacently overlap by 0% to 95%.

Further, the lines drawn twice adjacently overlap by 30%-60%.

Further, when performing the second irradiation operation, the second laser is used to perform multiple linear scans on the thin film layer along the normal direction of the preset contour direction to remove all the thin film layers in the invalid area.

Further, when the second laser performs multiple linear scans on the film layer along the normal direction of the preset contour direction, after one linear scan is completed, the spot of the second laser moves a second unit along the tangential direction of the preset contour to perform In the next linear scan, adjacent linear scan lines overlap by 0-95%.

Further, adjacent linear scanning lines overlap by 30%-70%.

Through the above-mentioned method, when the invalid area is cleared, it can be scanned continuously without splicing through multiple small areas as in the prior art, so that no splicing traces will be left, and continuous scanning can effectively improve Edge cleaning efficiency.

Further, when performing the second irradiation operation, the second laser overlaps the scribing area in the area formed by performing multiple linear scanning superimpositions, and the overlapping width is 0 to 95% of the normal width of the scribing area along the preset contour. %. It can not only ensure that the thermal impact on the effective area is small, but also ensure that the entire invalid area is cleaned.

Further, the first laser beam irradiates the film layer vertically to the glass substrate; the second laser beam irradiates the film layer vertically or obliquely to the glass substrate. Therefore, the design of the optical path and the equipment design for the edge cleaning process can be facilitated.

Further, the method further includes: performing the first irradiation operation and the second irradiation operation while performing a dust suction operation, so as to prevent the smoke and dust generated during the laser irradiation process from falling on the effective area and affecting the effective area.

Further, during the vacuuming operation, the vacuuming area covers the spot of the first laser and the spot of the second laser, which can improve the efficiency of vacuuming

Further, the normal width of the scribing area along the predetermined contour is 0.1-5 times of the spot diameter of the second laser. And in one embodiment, it is further defined that the normal width of the scribing area along the preset contour is 0.1 to 0.5 times the spot diameter of the second laser, so that it can effectively avoid damage to the effective area during the second irradiation operation. caused by thermal effects.

Further, the spot diameter of the first laser is 0.08-5 times of the spot diameter of the second laser.

Preferably, the spot diameter of the first laser is 0.2-0.6 times the spot diameter of the second laser.

On the other hand, provide a kind of device for realizing the laser edge cleaning method of the solar cell, comprising:

a laser light source capable of emitting a first laser and a second laser;

a driving mechanism, used to drive the laser light source to realize the tangential and/or normal movement of the spots of the first laser and the second laser along the preset contour;

The control unit is used to control the laser light source to emit the first laser and the second laser, and control the driving mechanism to adjust the movement track of the light spots of the first laser and the second laser; to perform the first irradiation operation, the first laser is used along the Scribing and dividing the thin film layer of the battery in a preset contour direction, dividing the thin film layer into an effective area and an invalid area; and performing a second irradiation operation, using a second laser to remove the thin film layer in the invalid area.

Further, the laser light source is one, and one laser is used to emit the first laser and the second laser.

Further, there are two laser light sources, one of which can emit the first laser, and the other laser can emit the second laser. Further, the device also includes a dust suction device, the dust suction port of the dust suction device can move synchronously with the spot of the first laser and/or the second laser, so that the dust suction port can absorb the first irradiation operation and the second laser light. 2. Smoke and dust during irradiation operation.

Compared with the prior art, the present invention has the following advantages: by performing the first irradiation operation, the thin film layer of the battery is scribed and divided along the predetermined contour direction with the first laser, and the thin film layer is divided into an effective area and an invalid area. Then, a second irradiation operation is performed, using a second laser, to remove the thin film layer in the invalid area. In the implementation process, the purpose of the first irradiation operation is only to divide the area, so as not to cause a large thermal impact on the effective area, and when the second irradiation operation clears the invalid area, because of the separation of the two areas, Therefore, no large edge thermal impact on the active area will be caused. Therefore, the method proposed by the present invention can effectively reduce the edge heat impact on the solar cell during the edge cleaning process.

At the same time, when performing the first irradiation operation, it can be completed by using a low-power laser, thereby reducing the cost. During the second irradiation operation, the invalid area can be scanned continuously, thereby avoiding stitching traces and greatly improving efficiency.

Description of drawings

Figure 1 is a schematic diagram of the structure of a perovskite battery;

Fig. 2 is the technological schematic diagram of existing edge cleaning method;

Fig. 3 is the partial schematic diagram of the process of existing edge cleaning method;

Fig. 4 is the flow chart of the edge clearing method proposed in the embodiment of the present invention;

Fig. 5 is a schematic diagram of dividing batteries in an embodiment of the present invention;

Fig. 6 is a schematic diagram of the direction of laser action during edge cleaning in an embodiment of the present invention;

7 is a schematic diagram of a first form of first and second laser irradiation in an embodiment of the present invention;

8 is a schematic diagram of a second form of first and second laser irradiation in an embodiment of the present invention;

9 is a schematic diagram of a third form of first and second laser irradiation in an embodiment of the present invention;

10 is a schematic diagram of a fourth form of first and second laser irradiation in an embodiment of the present invention;

Fig. 11 is a schematic diagram of the generated area and irradiation operation in the edge cleaning process in the embodiment of the present invention;

Fig. 12 is a schematic diagram during the first irradiation operation in an embodiment of the present invention;

Fig. 13 is a schematic diagram during the second irradiation operation in an embodiment of the present invention;

Fig. 14 is a schematic diagram of the dust cleaning operation in the embodiment of the present invention.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, but not all of them. The following description of at least one exemplary embodiment is merely illustrative in nature and in no way taken as limiting the invention, its application or uses. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Techniques, methods and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, such techniques, methods and devices should be considered part of the Authorized Specification.

It should be noted that like numerals and letters denote like items in the following figures, therefore, once an item is defined in one figure, it does not require further discussion in subsequent figures.

Moreover, the terms "first", "second" and the like are only for convenience of description, and should not be understood as limitations on the quantity and the like.

Since the overall shape of a solar cell is usually a rectangular structure, in order to enable those skilled in the art to understand the concept of the present invention more deeply, in the embodiments of the present invention, the process of edge cleaning of a rectangular solar cell structure will be described in detail.

Fig. 4 shows in one embodiment of the present invention, when carrying out solar cell edge clearing, flow chart, laser edge clearing method comprises:

Step S100: Execute the first irradiation operation, use the first laser to scribe and divide the thin film layer of the battery along the preset outline direction, and divide the thin film layer into an effective area and an inactive area.

Wherein, the preset contour refers to the contour remaining after the edge of the solar cell is removed. For example, in Fig. 5-6, after the edge cleaning of the solar cell is completed, the remaining area (effective area) is a rectangle, because in the production process In , the area and location of the reserved area are pre-designed, so the outline of the area is also known in advance. The purpose of the first irradiation operation is to separate the reserved area (effective area) from the edge area to be removed (invalid area). Therefore, the effective area is also the area to be reserved, and the invalid area is the edge area to be removed.

Step S200: performing a second irradiation operation, using a second laser to remove the thin film layer in the invalid area.

The purpose of this step is to achieve the final edge cleaning operation, because in the process of the first irradiation operation, the effective area and the invalid area have been separated, then through the second irradiation operation, all the film layers in the invalid area are directly removed , the edge cleaning process can be completed.

It can be seen that, using the technical solution in the embodiment of the present invention, the effective area and the invalid area are first divided through the first irradiation operation, and then the invalid area is cleared through the second irradiation operation, then the process of clearing the invalid area In the middle, it will not have a great impact on the effective area, even if the second laser power is greater, because it will only ablate the thin film layer in the ineffective area, it will not affect the effective area, so that the edge of the product will be heated The area of influence is small, thus ensuring the electrical conductivity of the solar cell. According to the procedures given in the above embodiments, the first irradiation operation and the second irradiation operation are performed sequentially, and the second irradiation operation is performed after the first irradiation operation is completed.

Because, in the embodiment of the present invention, because the first irradiation operation is only to divide the effective area and the invalid area, from another perspective, the function of the first laser is only for scribing and dividing. When the first laser is used for scribing and dividing, the area to be ablated by the laser is very small. Therefore, the power of the first laser does not need to be too high to meet the requirement of efficiency. The size of the heat-affected zone in the scribing process, while ensuring the scribing efficiency, the power of the first laser should be as small as possible. The purpose of the second irradiation operation is to quickly clear the invalid area, and because the invalid area and the effective area have been separated, when the laser scanning is performed on the invalid area, even if the power of the second laser is large, it will not affect the effective area. The area has a large thermal influence, so in order to improve the efficiency of edge cleaning, a relatively high-power laser can be used.

Therefore, considering the above factors, in the embodiment of the present invention, the first power is smaller than the second power, which can reduce thermal influence and take into account efficiency.

In the specific implementation of the embodiment of the present invention, the power range of the first laser is 1W-50W, which can meet the requirements of the first irradiation operation, which not only causes relatively small thermal impact, but also meets the requirements of efficiency. Through a large number of engineering tests, it is found that when the edge cleaning of perovskite solar cells is performed, when the power of the first laser is 15-25W, a relatively ideal effect can be achieved, and, in the preferred engineering implementation process, the first laser The power is selected as 20W. In addition, when using low-power lasers, the cost can also be reduced.

As for the second laser, of course, the larger the better, in the embodiment of the present invention, the second power is used in the range of 50W to 1000W, which can have relatively small thermal influence and take into account the efficiency of edge cleaning, and , through a large number of engineering tests, it is found that when the edge cleaning of perovskite solar cells is performed, when the power of the second laser is 150-300W, a relatively ideal effect can be achieved. In a specific embodiment, the power of the second laser is selected at 200W, which effectively balances efficiency and reduces thermal influence.

In one embodiment of the present invention, when the first irradiation operation is performed, the first laser light is directly irradiated on the film layer; while the second irradiation operation is performed, the second laser light is irradiated on the film layer through the glass substrate of the battery, That is, as shown in Figure 7, it can be seen that the first laser is irradiated directly on the film layer from above to complete the scribing operation; the second laser is irradiated from below, and the laser is irradiated on the film layer through the glass substrate, and the invalid area is irradiated. The middle film layer is removed.

In a preferred embodiment of the present invention, the range of the wave band of the first laser and the wave band of the second laser is 300nm-2000nm. In this wave band range, the thin film layer of the solar cell can absorb light waves better, thus more conducive to The thin film layer is ablated to complete the first irradiation operation and the second irradiation operation. In a preferred embodiment of the present invention, what the waveband of the first laser and the waveband of the second laser all adopt is 1064nm, under this waveband, the thin film layer of solar cell absorbs the light wave of laser more easily, makes the first irradiation operation and the second Both irradiation operations have good results.

In another embodiment of the present invention, the realization form shown in FIG. 8 can also be adopted, that is, when the first irradiation operation is performed, the first laser light is directly irradiated on the film layer; when the second irradiation operation is performed, the first Two lasers are directly irradiated on the film layer.

In another embodiment of the present invention, the third implementation form shown in FIG. 9 can also be adopted. When the first irradiation operation is performed, the first laser light is irradiated on the film layer through the glass substrate; the second irradiation operation is performed. In operation, the second laser light is irradiated on the thin film layer through the glass substrate.

Alternatively, in another embodiment, the fourth implementation form shown in FIG. 10 is also adopted, that is, the first laser light is irradiated on the film layer through the glass substrate, and the second laser light is directly irradiated on the film layer.

The above implementation forms can be comprehensively selected according to the design requirements of the edge cleaning device. For example, in the edge-clearing process of perovskite solar cells, the first form of implementation is adopted, and the optical path structure is relatively simple, which is more convenient for cost reduction.

In the embodiment of the present invention, the irradiation angles of the first laser and the second laser are not strictly limited, and the irradiation angles of the first laser and the second laser may be perpendicular to the glass substrate or oblique to the glass substrate.

It is worth noting that the more recommended implementation is that the first laser is irradiated perpendicularly to the glass substrate, which is more conducive to ensuring the straightness of the scribing line, improving the accuracy of the scribing line, and is also convenient for dust collection during the edge cleaning process.

In an embodiment of the present invention, when the first irradiation operation is performed, the first laser is used to scribe multiple times along the predetermined contour direction on the film layer, and the multiple scribed lines are superimposed to form a film with a certain width along the normal direction of the preset contour direction. The scribed area, as shown in Figure 11, the scribed area divides the thin film layer into an effective area and an inactive area.

Because for laser cutting, the smaller the spot, the better, because the larger the spot, the easier it is to cause laser damage, which will have a serious thermal impact on the effective area. Therefore, when the light spot is smaller, when only a line is drawn to divide the thin film layer into an effective area and an invalid area, although the division can be completed, the distance between the inactive area and the effective area is only the width of a light spot, so when performing During the second irradiation operation, the control accuracy of the edge cleaning equipment cannot meet the requirements, and it is very easy for the spot of the second laser to hit the effective area when cleaning the invalid area, thereby causing laser damage to the effective area. At the same time, if the width of the scribing line is too thin, the distance between the two areas will be too small, and the power of the second laser is relatively large, then when the invalid area is cleaned, when the second laser irradiates the invalid area close to the effective area so that , High-power lasers will generate higher heat. Although the ineffective area and the effective area are separated, the high heat will still cause a certain thermal impact on the effective area.

Therefore, in order to avoid the above problems, during the first irradiation operation, the first laser is used to scribe multiple times, and the scribe area divides the film layer into an effective area and an inactive area. As for how wide it needs to be, it can be adjusted according to actual needs. For example, if the focus spot of the second laser is larger, it can be wider; if the focus spot of the second laser is smaller, it can be narrower.

Specifically, usually the width can be determined according to the spot size of the second laser. Usually in a specific edge cleaning process, the width can be set to 0.1 to 5 times the spot diameter of the second laser, which can effectively avoid the thermal impact on the effective area during the second irradiation operation. However, when the width is too wide, the time for the first operation will increase. Therefore, in order to balance the efficiency and thermal influence, in the specific implementation process, the width can be set to 0.1~ 0.5 times can achieve the desired effect. In the implementation of the present invention, by controlling the spot diameter of the first laser to be 0.08-5 times of the spot diameter of the second spot, the two lasers can be effectively controlled to have an ideal scribing width. In a preferred embodiment of the present invention, the spot diameter of the first laser is controlled to be 0.2 to 0.6 times the spot diameter of the second spot, so that on the one hand, the efficiency of laser scribing is ensured, and at the same time, the two lasers have an ideal Line width.

In the first irradiation operation, in order to make the scribing area have a certain width because of multiple scribing operations, the first laser moves a first unit along the normal direction of the preset contour direction after completing one scribing , and then draw the next line. As shown in Figure 11-12, take the edge cleaning of the lower edge of the battery as an example. After the first laser completes a scribing along the X axis, the first laser moves along the Y axis by a first unit to perform the next scribing. For the first unit, it needs to be set according to the spot size of the first laser.

Ideally, it is hoped that two adjacent dashed lines can be seamlessly spliced, that is, the overlapping area of the lines is 0. However, due to certain errors in the equipment, it is relatively difficult to realize the seamless connection of the two lines. If you want to achieve seamless splicing, the accuracy of the equipment is very high, which will greatly increase the cost. In addition, in order to avoid traces of markings, two adjacent markings overlap to a certain extent, as shown in FIG. 12 , specifically, the overlap of two adjacent markings is 0-95%. In the specific implementation process, taking into account the efficiency and the accuracy of the equipment, it can be controlled within the overlapping range of 30% to 60%.

When performing the second irradiation operation, due to the spot limitation of the second laser, it is impossible to clear the entire area in one scan. Therefore, the second laser is directed along the normal direction of the preset contour (for example, for the lower edge shown in FIG. 11 , The normal direction is the Y-axis direction) to perform multiple linear scans on the film layer to remove all the film layers in the invalid area.

Based on the same principle as the first laser irradiation operation, when the second laser performs multiple linear scans on the film layer along the normal direction of the preset contour, after a linear scan is completed, the cut of the spot of the second laser along the direction of the preset contour Move to one second unit to perform the next linear scan, and the adjacent linear scan lines overlap by 0-95%, as shown in Figure 13 . However, in the specific implementation process, it can be controlled within the range of 30% to 70%. For the second unit, it needs to be set according to the spot size of the second laser. Through the above-mentioned method, when the invalid area is cleared, it can be scanned continuously without splicing through multiple small areas as in the prior art, so that no splicing traces will be left, and continuous scanning can effectively improve Edge cleaning efficiency.

In order to clear all the invalid areas, the second laser will inevitably scan the invalid area close to the edge of the scribed area during the irradiation process. The ideal state is still to hope that the spot of the second laser will not hit the scribed area. , but also because of the accuracy of the equipment, it is difficult to achieve the ideal state. Therefore, in order to clean the invalid area, the area scanned by the second laser must have a certain overlap with the scribing area, and the width of this overlapping area , in the specific implementation process, it is 0-95% of the normal width of the scribing area along the preset contour, and the specific position is shown in Figure 13. Get the desired effect. This can not only ensure that the thermal impact on the effective area is small, but also ensure that the entire invalid area is cleaned.

Further, in the embodiment of the present invention, while performing the first irradiation operation and the second irradiation operation, the dust suction operation is performed, because the purpose of doing so is that smoke and dust will be generated during the laser ablation process , and these dusts may fall in the effective area, thus causing damage to the effective area. The above problems can be avoided by performing dust removal while the laser is irradiating.

In the preferred implementation process, it is found that when the first irradiation operation is performed, the dust suction area covers the spot of the first laser light when the dust is sucked, as shown in Figure 14, that is, the dust suction area of the dust suction device can follow the first laser light spot. The spot of a laser moves, so that it can draw lines and vacuum at the same time, which effectively improves the efficiency of vacuuming, and at the same time reduces the impact of smoke on the effective area.

Similarly, for the same reason and purpose, when performing the first irradiation operation, when vacuuming, the dust suction area covers the spot of the second laser, that is, the dust suction area of the dust suction device can move with the spot of the second laser, In this way, it is possible to scan and clean while vacuuming.

The edge cleaning method proposed in the embodiments of the present invention can not only be applied to the edge cleaning process of perovskite thin-film batteries, but also can be applied to silicon-based thin-film batteries, cadmium telluride (CdTe) thin-film batteries, copper indium gallium In the edge-clearing process of solar thin-film batteries such as selenium (CIGS) thin-film batteries and gallium arsenide (GaAs) thin-film batteries, it has good versatility and can significantly improve the edge-clearing quality of existing solar cells.

In an embodiment of the present invention, there is also provided a device for realizing the above solar cell laser edge cleaning method, the device at least includes a laser light source, a drive mechanism and a control unit, wherein the laser light source can emit the first laser and second laser. For the laser light source, a dual-channel laser can be used to emit the first laser and the second laser, or it can be a single-channel laser with adjustable laser power. The second laser can also use two single-channel lasers. In a preferred embodiment of the present invention, two lasers are used, wherein a low-power laser is used to emit the first laser, and a high-power laser is used to emit the second laser.

The driving mechanism is used to drive the laser light source to realize the tangential and/or normal movement of the spots of the first laser and the second laser along the preset contour; in a specific embodiment, the driving mechanism can use high-precision The linear motor drives the movement of the laser light source. For example, when cleaning the edge of the perovskite battery shown in Figure 11, for each edge, two lasers are set, a high-power laser and a low-power laser, to For example, the first laser is irradiated from above, and the second laser is irradiated from below through the glass substrate. Two linear motors can be designed to drive a low-power laser or a high-power laser along the X-axis and Y-axis respectively. laser, so as to realize the tangential and/or normal movement of the spots of the first laser and the second laser along the preset contour.

Since the edge area that may need to be removed is not very large during the second irradiation operation, the second laser can be emitted through the vibrating mirror during the second laser irradiation. At this time, it is only necessary to use a linear motor to drive the second The laser can move along the preset contour direction.

The control unit is used to control the laser light source to emit the first laser and the second laser, and control the drive mechanism to adjust the movement track of the light spots of the first laser and the second laser; to perform the first irradiation operation, the first laser is used to Scribing and dividing the thin film layer of the battery in a predetermined contour direction, dividing the thin film layer into an effective area and an invalid area; and performing a second irradiation operation, using a second laser to remove the thin film layer in the invalid area. For example, a programmable controller can be used to control the emission time and power of the first laser and the second laser according to the process requirements, and to control the emission time and power of the second laser, and to control the driving mechanism to realize the track control of the spot, so as to perform the first irradiation operation and the second Irradiation operation.

Further, in an embodiment of the present invention, the edge cleaning device also includes a dust suction device, wherein the dust suction port of the dust suction device can be directly arranged at the light exit of the laser, so that the dust suction port can follow the first laser and/or The light spot of the second laser moves synchronously, so that when vacuuming, the suction port covers the light spots of the first laser and the second laser, thereby effectively improving the dust collection efficiency and avoiding damage to the effective area by smoke and dust.

With the above-mentioned device, the proposed edge cleaning method can be realized, and the edge heat effect caused is small when cleaning the edge.

Claims

A method for laser edge cleaning of solar cells, characterized in that it comprises:

Executing the first irradiation operation, using the first laser to scribe and divide the thin film layer of the battery along the preset contour direction, and divide the thin film layer into an effective area and an invalid area;

A second irradiation operation is performed, using a second laser, to remove the thin film layer in the inactive area.
The method according to claim 1, characterized in that, after the first irradiating operation is completed, the second irradiating operation is performed.
The method of claim 2, wherein the power of the first laser is less than the power of the second laser.
The method according to claim 3, characterized in that the power range of the first laser is 1W-50W, and the power range of the second laser is 50W-1000W.
The method according to claim 4, characterized in that, the wavelength bands of the first laser light and the second laser light are both in the range of 300nm-2000nm.
The method according to claim 5, characterized in that, when the first irradiation operation is performed, the first laser light is directly irradiated on the film layer; when the second irradiation operation is performed, the second laser light is irradiated on the film layer through the glass substrate of the battery superior.
The method according to claim 5, wherein when the first irradiation operation is performed, the first laser light is directly irradiated on the film layer; when the second irradiation operation is performed, the second laser light is directly irradiated on the film layer.
The method according to claim 5, characterized in that, when the first irradiation operation is performed, the first laser light is irradiated on the film layer through the glass substrate; when the second irradiation operation is performed, the second laser light is irradiated on the film layer through the glass substrate layer.
The method according to claim 5, characterized in that, when the first irradiation operation is performed, the first laser light is irradiated on the film layer through the glass substrate; when the second irradiation operation is performed, the second laser light is directly irradiated on the film layer.
The method according to any one of claims 1-9, characterized in that, when the first irradiation operation is performed, the first laser is used to scribe multiple times along the preset contour direction, and the multiple scribes are superimposed to form a The normal direction of the predetermined contour has a scribe area with a certain width, and the scribe area divides the film layer into an effective area and an inactive area.
The method according to claim 10, characterized in that, when the first laser is used to scribe the film layer along the preset contour direction for multiple times, after the scribing is completed once, the first laser along the preset contour direction Move one unit in the normal direction to draw the next line, and the lines drawn twice adjacent overlap by 0-95%.
The method according to claim 11, characterized in that the lines drawn twice adjacently overlap by 30%-60%.
The method according to claim 10, characterized in that, when performing the second irradiation operation, the film layer is linearly scanned multiple times along the normal direction of the preset contour direction by the second laser to remove the film layer in the invalid area.
The method according to claim 13, wherein when the second laser performs multiple linear scans on the film layer along the normal direction of the preset contour direction, after one linear scan is completed, the spot of the second laser follows the preset contour Tangentially move a second unit for the next linear scan, and adjacent linear scan lines overlap by 0-95%.
The method according to claim 14, characterized in that adjacent linear scanning lines overlap by 30%-70%.
The method according to claim 15, characterized in that, when the second irradiation operation is performed, the area formed by the superposition of multiple linear scans of the second laser overlaps the scribed area, and the width of the overlap is the scribed area along the predetermined Set the normal width of the outline to 0 to 95%.
The method according to claim 16, wherein the first laser beam irradiates the film layer vertically to the glass substrate; the second laser beam irradiates the film layer vertically or obliquely to the glass substrate.
The method according to claim 17, characterized in that the method further comprises: performing a dust suction operation while performing the first irradiation operation and the second irradiation operation.
The method according to claim 18, characterized in that, during the dust suction operation, the dust suction area covers the light spot of the first laser and the light spot of the second laser.
The method according to claim 10, characterized in that, the normal width of the scribing area along the preset contour is 0.1-5 times the spot diameter of the second laser.
The method according to claim 20, characterized in that, the normal width of the scribing area along the predetermined contour is 0.1-0.5 times the spot diameter of the second laser.
The method according to claim 21, characterized in that the spot diameter of the first laser is 0.08-5 times the spot diameter of the second laser.
The method according to claim 22, characterized in that the spot diameter of the first laser is 0.2-0.6 times the spot diameter of the second laser.
A device for realizing the solar cell laser edge cleaning method according to any one of claims 1-23, characterized in that it comprises:

a laser light source capable of emitting a first laser and a second laser;

a driving mechanism, used to drive the laser light source to realize the tangential and/or normal movement of the spots of the first laser and the second laser along the preset contour;

The control unit is used to control the laser light source to emit the first laser and the second laser, and control the driving mechanism to adjust the movement track of the light spots of the first laser and the second laser; to perform the first irradiation operation, the first laser is used along the Scribing and dividing the thin film layer of the battery in a preset contour direction, dividing the thin film layer into an effective area and an invalid area; and performing a second irradiation operation, using a second laser to remove the thin film layer in the invalid area.
The device according to claim 24, wherein the laser light source is a laser, and the first laser and the second laser are emitted by one laser.
The device according to claim 24, wherein the laser light source is two lasers, one of which can emit the first laser, and the other laser can emit the second laser.
The device according to any one of claims 24-26, characterized in that the device also includes a dust suction device, the dust suction port of the dust suction device can be synchronized with the spot of the first laser and/or the second laser Movement, so that the dust suction port can absorb the smoke and dust in the first irradiation operation and the second irradiation operation.