阅读说明：本技术 一种se叠瓦电池电极印刷系统的对位方法 (Alignment method of electrode printing system of SE (selective emitter) laminated cell ) 是由 方志文 林纲正 陈刚 于 2020-10-21 设计创作，主要内容包括：本发明公开了一种SE叠瓦电池电极印刷系统的对位方法,其中,放置于工作台上的待印刷硅片表面设有多条相互平行的副栅激光槽以及至少三个激光MARK点；设于支撑台上的网版上设有主栅线孔、副栅线孔和防断栅线孔,防断栅线孔包括用于丝网相机识别的第一防断栅线孔和第二防断栅线孔；所述对位方法包括先利用MARK点位置坐标信息进行工作台对位,然后再利用第一防断栅线孔的防断栅位置坐标信息进行支撑台对位。实施本发明,可方便丝网印刷定位,优化太阳能电池外观效果。(The invention discloses an alignment method of an electrode printing system of an SE (selective emitter) stack cell, wherein a plurality of mutually parallel auxiliary grid laser grooves and at least three laser MARK (MARK) points are arranged on the surface of a silicon wafer to be printed, which is placed on a workbench; a main grid line hole, an auxiliary grid line hole and an anti-breaking grid line hole are arranged on a screen plate arranged on the supporting table, and the anti-breaking grid line hole comprises a first anti-breaking grid line hole and a second anti-breaking grid line hole which are used for identification of a silk screen camera; the alignment method comprises the steps of firstly carrying out alignment on the workbench by utilizing MARK point position coordinate information, and then carrying out alignment on the support table by utilizing the anti-breakage grid position coordinate information of the first anti-breakage grid line hole. The invention can facilitate the screen printing positioning and optimize the appearance effect of the solar cell.)

1. An alignment method of an SE (element SE) stack cell electrode printing system comprises a controller, a workbench, a printing device and a silk screen camera, wherein the printing device and the silk screen camera are arranged above the workbench, the printing device comprises a support platform and a screen plate arranged on the support platform, and a silicon wafer to be printed is placed on the workbench; the method is characterized in that a plurality of mutually parallel auxiliary grid laser grooves and at least three laser MARK points are arranged on the surface of the silicon wafer to be printed;

the screen printing plate is provided with a main grid line hole, an auxiliary grid line hole and an anti-breakage grid line hole, wherein the anti-breakage grid line hole is arranged between adjacent auxiliary grid line holes and is vertical to the main grid line hole; the breakage-proof grid line hole comprises a first breakage-proof grid line hole and a second breakage-proof grid line hole which are used for identification of the silk screen camera;

the alignment method comprises the following steps:

(1) the controller acquires screen printing position coordinate information and silicon wafer printing position coordinate information uploaded by a user;

(2) loading a silicon wafer to be printed to the workbench;

(3) acquiring MARK point position coordinate information of a laser MARK point on a silicon wafer to be printed by a silk screen camera;

(4) the controller adjusts the position of the workbench according to the position coordinate information of the MARK point and the position coordinate information of the silicon chip printing;

(5) acquiring anti-breakage grid position coordinate information of the first anti-breakage grid line hole by a screen camera;

(6) and the controller adjusts the position of the support platform according to the position coordinate information of the anti-breaking grid and the position coordinate information of the screen printing.

2. The method for aligning an electrode printing system of a SE stack according to claim 1, wherein step (4) comprises:

the controller translates the workbench according to the position coordinate information of the MARK point and the position coordinate information of the silicon chip printing;

acquiring position coordinate information of a second MARK point of a laser MARK point on the silicon wafer to be printed after translation by the silk screen camera;

the controller compares the position coordinate information of the second MARK point with the position coordinate information of the silicon chip printing position;

if the position coordinate information of the second MARK point is the same as the position coordinate information of the silicon chip printing, finishing the alignment of the workbench;

and if the second MARK point position coordinate information is different from the silicon chip printing position coordinate information, rotating the workbench according to the second MARK point position coordinate information and the silicon chip printing position coordinate information so as to complete the alignment of the workbench.

3. The method of aligning an electrode printing system of an SE stack as set forth in claim 2, wherein a controller translates said stage according to the following equation

T_x＝(X₀-x₀)

T_y＝(Y₀-y₀)

Wherein, T_xFor the translation distance of the table in the X direction, T_yThe translation distance of the workbench in the Y direction; (X)₀，Y₀) Printing position coordinate information for silicon wafer, (x)₀，y₀) And MARK point position coordinate information of the laser MARK point.

4. The alignment method for the electrode printing system of the SE stack cell as claimed in claim 2, wherein the surface of the silicon wafer to be printed is provided with three laser MARK points which are distributed in a right triangle, and the right-angle side of the right triangle is parallel to the edge of the silicon wafer to be printed.

5. The method of aligning an electrode printing system of an SE stack according to claim 4, wherein a controller rotates the table according to the following equation

r＝|θ-α|

Wherein r is the rotation angle of the worktable, (X)₁，Y₁) And (X)₀，Y₀) Printing position coordinate information for silicon wafer, (x)₁，y₁) Position coordinate information of a second MARK point which is a laser MARK point located at a right-angled vertex position, (x)₂，y₂) Coordinate information of a second MARK point position of the laser MARK point positioned at the non-right-angle vertex position; alpha is a first deflection angle and theta is a second deflection angle.

6. The method of aligning an electrode printing system of an SE stack according to claim 4, wherein a controller rotates the table according to the following equation

r＝|β-ω|

Wherein r is the rotation angle of the worktable, (X)₁，Y₁) And (X)₀，Y₀) Printing position coordinate information for silicon wafer, (x)₁，y₁) The coordinate information of the position of a second MARK point of the laser MARK point positioned at the vertex of the right angle, beta is a third deflection angle, and omega is a fourth deflection angle.

7. The method for aligning an electrode printing system for an SE stack battery according to claim 4, wherein the laser MARK points are distributed in an isosceles right triangle.

8. The method of aligning an electrode printing system for an SE stack cell according to claim 1, wherein the screen comprises a printing area and a support area; the main grid line hole, the auxiliary grid line hole and the breakage-proof grid line hole are all arranged in the printing area;

the distance between the first anti-breaking grid line hole and the edge of the printing area is as follows: the width of the printing area is 1: (12-20).

9. The method for aligning electrode printing systems of SE stack cells according to claim 8, wherein the distance between the main gate line hole located at the outermost side of the printing region and the edge of the printing region is: the width of the printing area is 1: (4-10).

10. The alignment method of an electrode printing system of an SE stack battery as claimed in claim 1, wherein four first anti-breaking grid line holes are formed on the screen;

and a second anti-breakage grid wire hole is not arranged between the auxiliary grid wire holes close to the first anti-breakage grid wire hole.

Technical Field

The invention relates to the technical field of crystalline silicon solar cell electrode printing, in particular to a contraposition method of an SE (selective emitter) stack cell electrode printing system.

Background

The traditional solar cell pieces are connected by adopting metal welding strips, so that the traditional solar cell pieces are easy to break and corrode, and the welding strips occupy the light receiving area of the module; the power of the solar cell module is reduced. The more advanced technology is that the connection is carried out in a laminated tile mode, and the quantity of the battery pieces is effectively increased by changing the welding mode (adopting conductive adhesive for bonding) among the battery pieces in the same assembly area, so that the power of the assembly is improved.

For the SE cell, since the sub-gate electrode thereof needs to be printed into the laser groove, the requirement for printing accuracy is high. Therefore, the alignment is often performed in a dual alignment manner; the first counterpoint is counterpoint by using a laser MARK point on the surface of the silicon wafer, and the second counterpoint is counterpoint by using a printing characteristic point arranged on a screen printing plate. The conventional SE cell hides the printed feature points in the main grid and, correspondingly, the screen camera is also disposed near the main grid of the conventional SE cell. However, when a string of stacked cells is made using SE cells, it is often necessary to shift the position of the main grid of the conventional SE cell. Therefore, if the printed feature points are hidden in the main grid, the position of the printing stage camera needs to be moved, which is difficult, and a lot of man-hours are needed to be consumed, which affects the production performance. If the positions of the printed feature points are not moved, the feature points are displayed in the electrode patterns, and the appearance of the solar cell is affected. In addition, in order to improve the printing precision, a plurality of laser MARK points (more than or equal to 4) are often arranged on the surface of the silicon wafer, the appearance quality of the SE stack-tile battery is also reduced, and the risk of hidden cracking of the SE stack-tile battery is improved.

Disclosure of Invention

The invention aims to solve the technical problem of providing an alignment method of an electrode printing system of an SE (element SE) laminated cell, which is convenient for a screen camera to grab and align, is convenient for screen printing and improves the appearance quality of a finished product.

In order to solve the technical problem, the invention provides an alignment method of an SE (element SE) stack cell electrode printing system, wherein the SE stack cell electrode printing system comprises a controller, a workbench, a printing device and a silk screen camera, wherein the printing device and the silk screen camera are arranged above the workbench;

the screen printing plate is provided with a main grid line hole, an auxiliary grid line hole and an anti-breakage grid line hole, wherein the anti-breakage grid line hole is arranged between adjacent auxiliary grid line holes and is vertical to the main grid line hole; the breakage-proof grid line hole comprises a first breakage-proof grid line hole and a second breakage-proof grid line hole which are used for identification of the silk screen camera;

the alignment method comprises the following steps:

(1) the controller acquires screen printing position coordinate information and silicon wafer printing position coordinate information uploaded by a user;

(2) loading a silicon wafer to be printed to the workbench;

(3) acquiring MARK point position coordinate information of a laser MARK point on a silicon wafer to be printed by a silk screen camera;

(4) the controller adjusts the position of the workbench according to the position coordinate information of the MARK point and the position coordinate information of the silicon chip printing;

(5) acquiring anti-breakage grid position coordinate information of the first anti-breakage grid line hole by a screen camera;

(6) and the controller adjusts the position of the support platform according to the position coordinate information of the anti-breaking grid and the position coordinate information of the screen printing.

As an improvement of the technical scheme, the step (4) comprises the following steps:

the controller translates the workbench according to the position coordinate information of the MARK point and the position coordinate information of the silicon chip printing;

acquiring position coordinate information of a second MARK point of a laser MARK point on the silicon wafer to be printed after translation by the silk screen camera;

the controller compares the position coordinate information of the second MARK point with the position coordinate information of the silicon chip printing position;

if the position coordinate information of the second MARK point is the same as the position coordinate information of the silicon chip printing, finishing the alignment of the workbench;

and if the second MARK point position coordinate information is different from the silicon chip printing position coordinate information, rotating the workbench according to the second MARK point position coordinate information and the silicon chip printing position coordinate information so as to complete the alignment of the workbench.

As an improvement of the technical scheme, the controller translates the workbench according to the following formula group

T_x＝(X₀-x₀)

T_y＝(Y₀-y₀)

Wherein, T_xFor the translation distance of the table in the X direction, T_yThe translation distance of the workbench in the Y direction; (X)₀，Y₀) Printing position coordinate information for silicon wafer, (x)₀，y₀) And MARK point position coordinate information of the laser MARK point.

As an improvement of the technical scheme, the surface of the silicon wafer to be printed is provided with three laser MARK points which are distributed in a right triangle, and the right-angle side of the right triangle is parallel to the edge of the silicon wafer to be printed.

As an improvement of the technical proposal, the controller rotates the worktable according to the following formula group

r＝|θ-α|

Wherein r is the rotation angle of the worktable, (X)₁，Y₁) And (X)₀，Y₀) Printing position coordinate information for silicon wafer, (x)₁，y₁) Position coordinate information of a second MARK point which is a laser MARK point located at a right-angled vertex position, (x)₂，y₂) Coordinate information of a second MARK point position of the laser MARK point positioned at the non-right-angle vertex position; alpha is a first deflection angle and theta is a second deflection angle.

As an improvement of the technical proposal, the controller rotates the worktable according to the following formula group

r＝|β-ω|

Wherein r is the rotation angle of the worktable, (X)₁，Y₁) And (X)₀，Y₀) Printing position coordinate information for silicon wafer, (x)₁，y₁) The coordinate information of the position of a second MARK point of the laser MARK point positioned at the non-right-angle vertex position is shown, beta is a third deflection angle, and omega is a fourth deflection angle.

As an improvement of the technical scheme, the laser MARK points are distributed in an isosceles right triangle shape.

As an improvement of the above technical solution, the screen printing plate comprises a printing area and a supporting area; the main grid line hole, the auxiliary grid line hole and the breakage-proof grid line hole are all arranged in the printing area;

the distance between the first anti-breaking grid line hole and the edge of the printing area is as follows: the width of the printing area is 1: (12-20).

As an improvement of the above technical solution, a distance between a main gate line hole located at the outermost side of the printing area and an edge of the printing area is as follows: width of printing area 1: (4-10).

As an improvement of the above technical scheme, four first anti-breaking grid line holes are formed in the screen printing plate;

and a second anti-breakage grid wire hole is not arranged between the auxiliary grid wire holes close to the first anti-breakage grid wire hole.

The implementation of the invention has the following beneficial effects:

1. according to the electrode printing system of the SE laminated cell, the first anti-breaking grid line hole in the screen printing plate is used as a printing characteristic point, so that the grabbing and positioning of a screen camera in the later period are not influenced, and the electrode structure is convenient to screen print; meanwhile, the influence of the printed characteristic points on the appearance of the SE laminated cell is avoided.

2. According to the electrode printing system of the SE laminated cell, only three laser MARK points are arranged on the surface of the silicon wafer to be printed, so that damage to the silicon wafer is reduced, and the hidden cracking of the later-stage slice is prevented; meanwhile, the alignment of the silicon wafer before printing is effectively ensured by a specific setting position and an alignment method, and the printing precision is not influenced; in addition, the appearance quality of the SE stack cell is improved by reducing the laser MARK points.

3. According to the alignment method of the SE stack cell electrode printing system, firstly, a silicon wafer to be printed is aligned through a laser MARK point, and then the first hole of a first anti-breaking grid is aligned with a screen printing plate; the alignment mode can effectively improve the printing precision. And the alignment precision is effectively ensured by controlling the number and the distribution position of the laser MARK points.

Drawings

FIG. 1 is a schematic diagram of an electrode printing system for an SE stack in accordance with an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a silicon wafer to be printed according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a screen printing plate according to an embodiment of the present invention;

FIG. 4 is an enlarged view of a portion of FIG. 3 at A;

FIG. 5 is a flow chart of a method for aligning an electrode printing system of an SE stack in accordance with an embodiment of the present invention;

FIG. 6 is a flowchart illustrating the step of S4 according to an embodiment of the present invention;

FIG. 7 is a schematic diagram illustrating a method for calculating a rotation angle of a stage according to an embodiment of the present invention;

FIG. 8 is a schematic diagram illustrating a method for calculating a rotation angle of a table according to another embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings.

Referring to fig. 1, as a first aspect of the present invention, an SE stack battery electrode printing system includes a controller, a table, a printing device, and a screen camera, the printing device and the screen camera being sequentially disposed above the table; the silicon wafer 1 to be printed is placed on a table.

Referring to fig. 2, the front surface of the silicon wafer 1 to be printed is provided with a plurality of sub-gate laser grooves 11 and at least three laser MARK dots 12, which are parallel to each other. The number of laser MARK spots 12 may be 3, 4, 5, or 6, but is not limited thereto. Preferably, in the embodiment, three MARK points are arranged on the front surface of the silicon wafer 1 to be printed, and the three MARK points are distributed in a triangular shape, so that the deviation between the silicon wafer 1 to be printed and a preset printing position can be effectively determined in the distribution form, a data base is provided for adjusting the placement angle of the silicon wafer 1 to be printed, and the printing precision is ensured; meanwhile, the damage of the SE laminated cell is reduced, and the probability of silicon chip subfissure in the later slicing process is reduced. In addition, the appearance quality of the SE stack-tile battery can be improved by reducing the laser MARK points, the laser engraving time can be shortened, and the production efficiency is improved.

Furthermore, the three MARK points are distributed in a right triangle shape, and the right-angle sides of the MARK points are parallel to the edge of the silicon chip, so that the distribution mode can greatly simplify the calculation of printing position deviation and ensure the printing alignment precision. Furthermore, the three laser MARK points are distributed in an isosceles right triangle shape, and the laser MARK points are arranged close to the edge of the silicon wafer 1 to be printed, so that the arrangement mode is more convenient for calculating the offset position.

Specifically, the printing apparatus of the present invention includes a support table and a screen 2 provided on the support table. Referring to fig. 3, the screen includes a printing zone and a support zone; a main grid hole 21, an auxiliary grid hole 22 and a breakage-proof grid hole 23 are arranged in the supporting area, wherein the main grid hole 21 is perpendicular to the auxiliary grid hole 22 and is parallel to the breakage-proof grid hole 23. The breakage-preventing gate wire hole 23 is provided between the adjacent sub-gate wire holes 22, and the breakage-preventing gate wire hole 23 includes a first breakage-preventing gate wire hole 231 and a second breakage-preventing gate wire hole 232. Among them, the first breakage preventing gate hole 231 is used for screen camera recognition. According to the invention, the first anti-breaking grid hole 231 is used as a printing characteristic point, so that the smooth proceeding of the subsequent screen printing process is ensured; and the two prevent the appearance of the finished battery product from being influenced by the exposure of the printing characteristic points. In addition, when the common SE battery and the SE stack battery are transferred, a printing table camera does not need to be moved, and the production capacity is not influenced.

Specifically, referring to fig. 4, in the present embodiment, the distance between the first breakage prevention gate hole 231 and the edge of the printing area (L1, L2): width (D) of printing region 1: (10-20), the first anti-breaking grid line hole 231 at this position can ensure accurate identification of the screen camera. Preferably, L1: d is 1: (14-18), L2: d is 1: (12-16).

Specifically, in the present embodiment, the distance between the main gate hole 21 located on the outermost side and the edge of the printed area (L3): width (D) of printing region 1: (4-10), L3 > L1 and L2. This is determined by the arrangement of the main grid electrode, the sub-grid electrode and the anti-breaking grid of the shingled cell. Preferably, L3: d ═ 1:5, but is not limited thereto.

Further, in order to facilitate the first breakage prevention gate hole 231 to be recognized by the screen camera, in the present embodiment, the second breakage prevention gate hole 232 is not provided between the sub-gate holes 22 adjacent to the first breakage prevention gate hole 231.

In addition, for convenience of recognition, four first breakage preventing grid line holes 231 are provided in the printing area, which are provided near the edge of the printing camera, to facilitate the screen camera to grasp.

Referring to fig. 5, as a second aspect of the present invention, there is provided an aligning method of an electrode printing system of an SE stack cell, comprising the steps of:

s1: the controller acquires screen printing position coordinate information and silicon wafer printing position coordinate information uploaded by a user;

specifically, the screen printing position coordinate information refers to coordinates of a screen position determined based on a predetermined battery electrode structure design. In the present embodiment, the screen printing position coordinate information includes coordinate information of the four printing feature points (the first breakage preventing gate holes 231) after the alignment, but is not limited thereto.

The silicon chip printing position coordinate information refers to the coordinate of a laser MARK point determined according to the preset battery electrode structure design. In this embodiment, the silicon wafer printing position coordinate information includes coordinate information of the three laser MARK points after alignment, but is not limited thereto.

S2: loading a silicon wafer to be printed to a workbench;

specifically, the silicon wafer after diffusion, film coating and laser grooving is transported and then loaded to a workbench.

S3: acquiring MARK point position coordinate information of a laser MARK point on a silicon wafer to be printed by a silk screen camera;

specifically, the MARK point position coordinate information refers to actual coordinate information of a laser MARK point on a silicon wafer to be printed, which is loaded on the workbench. In the present embodiment, it includes specific coordinate information of three laser MARK points, but is not limited thereto.

S4: the controller adjusts the position of the workbench according to the position coordinate information of the MARK point and the position coordinate information of the silicon chip printing;

specifically, referring to fig. 6, S4 includes:

s41: the controller translates the workbench according to the position coordinate information of the MARK point and the position coordinate information of the silicon chip printing;

specifically, the controller translates the table according to the following formula

T_x＝(X₀-x₀)

T_y＝(Y₀-y₀)

Wherein, T_xFor the translation distance of the table in the X direction, T_yThe translation distance of the workbench in the Y direction; (X)₀，Y₀) Printing position coordinate information for silicon wafer, (x)₀，y₀) And MARK point position coordinate information of the laser MARK point.

Preferably, the translation distance is calculated by taking the position coordinate information of the laser MARK point a0 located at the non-right-angle vertex position as a reference during translation.

S42: acquiring position coordinate information of a second MARK point of a laser MARK point on the silicon wafer to be printed after translation by the silk screen camera;

specifically, the second MARK point position coordinate information refers to actual coordinate information of a laser MARK point on the silicon wafer to be printed after translation. In the present embodiment, it includes specific coordinate information of three laser MARK points, but is not limited thereto.

S43: judging whether the alignment is finished;

specifically, the controller compares the position coordinate information of the second MARK point with the position coordinate information of the silicon chip printing position; if the position coordinate information of the second MARK point is the same as the position coordinate information of the silicon chip printing, finishing the alignment of the workbench;

if the position coordinate information of the second MARK point is different from the position coordinate information of the silicon chip printing, the step S44 is carried out;

s44: and rotating the workbench according to the position coordinate information of the second MARK point and the position coordinate information of the silicon chip printing.

Specifically, referring to FIG. 7, in one embodiment of the present invention, the controller rotates the table according to the following formula set

r＝|θ-α|

Wherein r is the rotation angle of the worktable, (X)₁，Y₁) And (X)₀，Y₀) Printing position coordinate information for silicon wafer, (x)₁，y₁) Position coordinate information of a second MARK point which is a laser MARK point located at a right-angled vertex position, (x)₂，y₂) Coordinate information of a second MARK point position of the laser MARK point positioned at the non-right-angle vertex position; alpha is a first deflection angle and theta is a second deflection angle.

Specifically, α is a deflection angle between the silicon wafer located at the printing position and the coordinate system, and may be any angle. Preferably 0.

Specifically, referring to fig. 7, during rotation, a0 is taken as a rotation center; meanwhile, a0 is also a position reference point when translating. The direction of rotation can be determined from the sign of r,

referring to fig. 8, in another embodiment of the present invention, the controller rotates the table according to the following formula set

r＝|β-ω|

Wherein r is the rotation angle of the worktable, (X)₁，Y₁) And (X)₀，Y₀) Printing position coordinate information for silicon wafer, (x)₁，y₁) The coordinate information of the position of a second MARK point of the laser MARK point positioned at the vertex of the right angle, beta is a third deflection angle, and omega is a fourth deflection angle.

Specifically, β is a deflection angle between the silicon wafer at the printing position and the coordinate system, and may be any angle. Preferably 0.

Specifically, referring to fig. 8, during rotation, a2 is taken as a rotation center; a2 is the non-right angle vertex of the right triangle A0A1A 2. When translating, the position reference point is A0.

S5: the method comprises the steps that a screen camera obtains anti-breakage grid position coordinate information of a first anti-breakage grid line hole;

specifically, the information of the position coordinates of the breakage-proof grid refers to the actual coordinate information of the first breakage-proof grid line hole on the screen printing plate. In the present embodiment, it includes specific coordinate information of four breakage prevention gate holes, but is not limited thereto.

S6: and the controller adjusts the position of the support table according to the position coordinate information of the anti-breaking grid and the position coordinate information of the screen printing.

Specifically, the adjustment method can refer to the existing MARK point alignment mode. Such as the method provided in CN 108493267A.

While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention.