阅读说明：本技术 用于印刷太阳能电池的二次印刷网版结构及方法 (Secondary printing screen structure and method for printing solar cell ) 是由 蔡富得 简锡添 于 2020-03-26 设计创作，主要内容包括：本发明提供了一种用于印刷太阳能电池的二次印刷网版结构及方法,所述二次印刷网版结构包括：一第一印刷网版,包括：一第一网框；一第一网布,拉伸并固定于所述第一网框上,且所述第一网布包括一第一刮刀面与一第一贴印面；一第一高分子材料层,包覆所述第一网布,且所述第一高分子材料层包括复数个指状式电极图案；其中,所述多个指状式电极图案的每一个的左侧及/或右侧于所述第一贴印面的一侧上包括复数个凹部,所述多个凹部位于所述多个指状式电极图案的每一个的左侧及/或右侧上；其中,所述第一网布上包括复数个预留部分,所述多个预留部分是与一待印物上的复数个整片式电极接触。本发明的方案提升了太阳能电池的发电效率。(The invention provides a secondary printing screen structure and a method for printing a solar cell, wherein the secondary printing screen structure comprises: a first printing screen comprising: a first frame; the first screen cloth is stretched and fixed on the first screen frame and comprises a first scraper surface and a first pasting surface; the first polymer material layer covers the first mesh cloth and comprises a plurality of finger-shaped electrode patterns; wherein the left side and/or the right side of each of the plurality of finger-shaped electrode patterns comprises a plurality of concave parts on one side of the first pasting surface, and the plurality of concave parts are positioned on the left side and/or the right side of each of the plurality of finger-shaped electrode patterns; the first mesh cloth comprises a plurality of reserved parts, and the reserved parts are in contact with a plurality of whole-piece electrodes on an object to be printed. The scheme of the invention improves the power generation efficiency of the solar cell.)

1. A secondary printing screen structure for printing solar cells, comprising:

a first printing screen comprising:

a first frame;

the first screen cloth is stretched and fixed on the first screen frame and comprises a first scraper surface and a first pasting surface;

the first polymer material layer covers the first mesh cloth and comprises a plurality of finger-shaped electrode patterns;

wherein the left side and/or the right side of each of the plurality of finger-shaped electrode patterns comprises a plurality of concave parts on one side of the first pasting surface, and the plurality of concave parts are positioned on the left side and/or the right side of each of the plurality of finger-shaped electrode patterns;

the first mesh cloth comprises a plurality of reserved parts, and the reserved parts are in contact with a plurality of whole-piece electrodes on an object to be printed.

2. The secondary printing screen structure of claim 1, further comprising:

a second printing screen comprising:

a second frame;

the second screen cloth is stretched and fixed on the second screen frame and comprises a second scraper surface and a second pasting surface;

the second polymer material layer covers the second mesh cloth and comprises a plurality of integral electrode patterns;

each of the plurality of integral type electrode patterns comprises a plurality of convex parts on one side of the second pasting surface, and the plurality of convex parts are positioned on the left side and the right side of each of the plurality of integral type electrode patterns.

3. The secondary printing screen structure of claim 2, wherein each of the plurality of full-sheet electrode patterns comprises a first height, and each of the plurality of protrusions comprises a second height, and the second height is 5 to 30 μm.

4. The secondary printing screen structure of claim 1, wherein each of the plurality of finger electrode patterns comprises a first length and each of the plurality of recesses comprises a second length, the second length being any value in a range of 1/3 to 1/10 of the width of the plurality of full-sheet electrodes.

5. A manufacturing method of a secondary printing screen structure for printing a solar cell is characterized by comprising the following steps:

coating and forming a first polymer material layer on a first screen cloth of a first printing screen, wherein the first screen cloth comprises a first scraper surface and a first pasting surface;

forming a plurality of finger-shaped electrode patterns on one side of the first polymer material layer on the first pasting surface through an etching process; and

and forming a plurality of concave parts on the left side and/or the right side of each of the plurality of finger-shaped electrode patterns on one side of the first polymer material layer on the first pasting surface through the etching process.

6. The method for manufacturing a secondary printing screen structure according to claim 5, further comprising:

coating a second mesh of a second printing screen and forming a second polymer material layer, wherein the second mesh comprises a second scraper surface and a second pasting surface;

forming a plurality of integral electrode patterns on the second polymer material layer by the etching process; and

and forming a plurality of convex parts on the left side and the right side of each of the plurality of integral type electrode patterns on one side of the second polymer material layer positioned on the second pasting printing surface through the etching process.

7. The method of claim 6, wherein each of the plurality of electrode patterns comprises a first height, each of the plurality of protrusions comprises a second height, and the second height is 5 to 30 μm.

8. The method of claim 5, wherein each of the plurality of finger electrode patterns comprises a first length, and each of the plurality of recesses comprises a second length, the second length being any value in a range of 1/3-1/10 of a width of a one-piece electrode.

9. The method of claim 5, wherein the etching process is a laser etching process.

10. A secondary printing method of a secondary printing screen structure, which is applied to the secondary printing screen structure of claim 1, comprising:

the slurry penetrates through the plurality of integral type electrode patterns and forms a plurality of integral type electrodes on an object to be printed; and

aligning the plurality of monolithic electrodes through the plurality of reserved portions, and passing the paste through the plurality of finger electrode patterns and the plurality of recesses and forming a plurality of finger electrodes on the object to be printed, wherein each of the plurality of finger electrodes is bonded to the plurality of monolithic electrodes through a half-cut left side and/or a half-cut right side.

11. The secondary printing method of the secondary printing screen structure of claim 10, wherein the half-cut left side and/or the half-cut right side of each of the plurality of finger electrodes has a height, and the height is any value in a range of 5 to 30 μm.

Technical Field

The present invention relates to a printing screen for printing a solar cell, a method for manufacturing the printing screen, and a printing method using the printing screen, and more particularly, to a secondary printing screen structure and a method for secondary printing of a solar cell.

Background

In the prior art, the structure of the solar cell usually includes Finger electrodes (Finger lines) and monolithic electrodes (Bus bars), and most solar cell designs use very fine Finger electrodes to transfer the photoelectrons collected from the active area to the larger monolithic electrodes and then to the circuit system of the module. In order to increase the efficiency of the solar cell, the finger electrodes are designed to be thin and high, so that the aspect ratio in the solar cell structure is good and the energy conversion efficiency is high. In the prior art, the finger-shaped electrodes are perpendicular to the whole-piece electrodes and are distributed on a silicon chip (wafer) in an equidistant manner, and the finger-shaped electrodes become thinner and thinner as the screening technology is improved.

In the prior art, two electrodes of a solar cell are mainly manufactured by a secondary printing technology, wherein the secondary printing means that Bus bar is printed on an object to be printed by primary printing, and then Finger line is printed on the object to be printed with Bus bar by secondary printing, so that the two electrodes of the solar cell can be formed on the object to be printed.

FIG. 1 is a schematic diagram illustrating a prior art printing screen structure for one-time printing; FIG. 2 is a schematic diagram illustrating a prior art printing screen structure for secondary printing; FIG. 3 is a schematic view illustrating a part of a printed object in the prior art; fig. 4 is a schematic side view illustrating a part of a printed object in the prior art. Please refer to fig. 1 to 4. Fig. 1 shows a primary printing screen 10 for making Bus bar, the primary printing screen 10 mainly includes a mesh 101 coated with an emulsion layer and a Bus bar pattern 103 formed on the mesh 101 by exposure and development, in the prior art, a Bus bar electrode 1031 is formed on an object to be printed 14 by using the primary printing screen 10, as shown in fig. 3 and 4. Fig. 2 shows that the secondary printing screen 12 for producing the fingerline is a screen 12, and the secondary printing screen 12 mainly includes a mesh 121 coated with an emulsion layer and fingerline patterns 123 formed on the mesh 121 by exposure and development. In the prior art, after the Bus bar electrode 1031 is formed on the object to be printed 14, the second printing screen 12 is used again to form a fingerline electrode 1231 on the object to be printed 14, and the fingerline electrode 1231 is bridged over the Bus bar electrode 1031, so that the fingerline electrode 1231 and the Bus bar electrode 1031 are in contact with each other and are electrically conductive, as shown in fig. 3 and 4.

However, in the prior art, when the Bus Bar electrode 1031 is printed on the object 14 and the Finger line electrode 1231 is printed next, the secondary printing screen 12 easily collides with the Bus Bar electrode 1031 on the object 14, which may damage the original Bus Bar electrode 1031. Furthermore, since the Finger line electrode 1231 is bridged over the Bus bar electrode 1031, a gap may be generated between the Finger line electrode 1231 and the Bus bar electrode 1031, which may cause poor contact or too much contact between the Bus bar electrode 1031 and the Finger line electrode 1231 at the bridged portion, which may cause large fluctuation between the two electrodes, thereby affecting the power generation efficiency of the solar cell.

For the above reasons, it is an object of the present invention to provide a novel screen printing plate for printing a solar cell, a method for manufacturing the screen printing plate, and a printing method using the screen printing plate, so that a solar electrode produced by using a secondary printing process has a better power generation efficiency.

Disclosure of Invention

The embodiment of the invention provides a secondary printing screen structure and a method for printing a solar cell, which are used for solving the problem of improving the power generation efficiency of the solar cell.

In order to solve the above technical problem, the present invention provides a secondary printing screen structure for printing a solar cell, comprising: a first printing screen comprising: a first frame; the first screen cloth is stretched and fixed on the first screen frame and comprises a first scraper surface and a first pasting surface; the first polymer material layer covers the first mesh cloth and comprises a plurality of finger-shaped electrode patterns; wherein the left side and/or the right side of each of the plurality of finger-shaped electrode patterns comprises a plurality of concave parts on one side of the first pasting surface, and the plurality of concave parts are positioned on the left side and/or the right side of each of the plurality of finger-shaped electrode patterns; the first mesh cloth comprises a plurality of reserved parts, and the reserved parts are in contact with a plurality of whole-piece electrodes on an object to be printed.

Moreover, the secondary printing screen structure of the invention further comprises: a second printing screen comprising: a second frame; the second screen cloth is stretched and fixed on the second screen frame and comprises a second scraper surface and a second pasting surface; the second polymer material layer covers the second mesh cloth and comprises a plurality of integral electrode patterns; each of the plurality of integral type electrode patterns comprises a plurality of convex parts on one side of the second pasting surface, and the plurality of convex parts are positioned on the left side and the right side of each of the plurality of integral type electrode patterns.

Preferably, each of the plurality of monolithic electrode patterns includes a first height, and each of the plurality of protrusions includes a second height, the second height being 5 to 30 μm.

Preferably, each of the plurality of finger electrode patterns comprises a first length, and each of the plurality of recesses comprises a second length, the second length being any value in the range of 1/3 to 1/10 of the width of the plurality of full-sheet electrodes.

In another aspect, the present invention further provides a method for manufacturing a secondary printing screen structure for printing a solar cell, including: coating and forming a first polymer material layer on a first screen cloth of a first printing screen, wherein the first screen cloth comprises a first scraper surface and a first pasting surface; forming a plurality of finger-shaped electrode patterns on one side of the first polymer material layer on the first pasting surface through an etching process; and forming a plurality of concave parts on the left side and/or the right side of each of the plurality of finger-shaped electrode patterns on one side of the first polymer material layer on the first pasting surface through the etching process.

Furthermore, the manufacturing method of the secondary printing screen structure further comprises the following steps: coating a second mesh of a second printing screen and forming a second polymer material layer, wherein the second mesh comprises a second scraper surface and a second pasting surface; forming a plurality of integral electrode patterns on the second polymer material layer by the etching process; and forming a plurality of convex parts on the left side and the right side of each of the plurality of integral type electrode patterns on one side of the second polymer material layer positioned on the second pasting printing surface through the etching process.

Preferably, each of the plurality of monolithic electrode patterns includes a first height, and each of the plurality of protrusions includes a second height, the second height being 5 to 30 μm.

Preferably, each of the plurality of finger electrode patterns includes a first length, and each of the plurality of recesses includes a second length, the second length being any value in a range of 1/3 to 1/10 of a width of a one-piece electrode.

Preferably, the etching process is a laser etching process.

In addition, the invention also provides a secondary printing method, which is applied to the secondary printing screen structure and comprises the following steps: the slurry penetrates through the plurality of integral type electrode patterns and forms a plurality of integral type electrodes on an object to be printed; and aligning the plurality of monolithic electrodes through the plurality of reserved portions, and passing the paste through the plurality of finger electrode patterns and the plurality of recesses and forming a plurality of finger electrodes on the object to be printed, wherein each of the plurality of finger electrodes is bonded to the plurality of monolithic electrodes through a half-cut left side and/or a half-cut right side.

Preferably, the left half-cut side and/or the right half-cut side of each of the plurality of finger electrodes has a height, and the height is any value in a range of 5 to 30 μm.

The invention has the beneficial effects that:

in the above scheme, the secondary printing screen structure includes: a first printing screen comprising: a first frame; the first screen cloth is stretched and fixed on the first screen frame and comprises a first scraper surface and a first pasting surface; the first polymer material layer covers the first mesh cloth and comprises a plurality of finger-shaped electrode patterns; wherein the left side and/or the right side of each of the plurality of finger-shaped electrode patterns comprises a plurality of concave parts on one side of the first pasting surface, and the plurality of concave parts are positioned on the left side and/or the right side of each of the plurality of finger-shaped electrode patterns; the first mesh cloth comprises a plurality of reserved parts, and the reserved parts are in contact with a plurality of whole-piece electrodes on an object to be printed. The scheme of the invention ensures that the integral electrode and the finger-shaped electrode have better contact effect, thereby improving the power generation efficiency of the solar cell.

Drawings

FIG. 1 is a schematic diagram of a printing screen structure for one-time printing in the prior art;

FIG. 2 is a schematic view of a prior art printing screen structure for secondary printing;

FIG. 3 is a schematic view of a printed part of an object to be printed in the prior art;

FIG. 4 is a schematic side view of a printed object to be printed in the prior art;

fig. 5 is a schematic view of a printing screen structure for secondary printing according to an embodiment of the present invention;

fig. 6 is a schematic view of a printing screen structure for one-time printing according to another embodiment of the present invention;

FIG. 7 is a schematic view of the cross-sectional structure A-A shown in FIG. 5 with an increased relationship with the object to be printed;

FIG. 8 is a schematic view of the cross-sectional structure A-A of FIG. 6;

fig. 9 is a flowchart of a method for manufacturing a secondary printing screen structure for printing a solar cell according to another embodiment of the present invention;

fig. 10 is a flowchart of a method for manufacturing a secondary printing screen structure for printing a solar cell according to another embodiment of the present invention;

fig. 11 is a flowchart of a secondary printing method using the secondary printing screen structure of the present invention according to another embodiment of the present invention;

fig. 12 is a schematic view of a part of a printed object after being printed by the printing screen structure according to an embodiment of the present invention;

fig. 13 is a schematic view of a part of a structure of an object to be printed after being printed by the printing screen structure according to an embodiment of the present invention;

fig. 14 is a schematic view of a part of an object to be printed after being printed by the printing screen structure according to another embodiment of the present invention;

fig. 15 is a side view of a part of an object to be printed after being printed by the printing screen structure according to another embodiment of the present invention.

Description of reference numerals:

10-one-time screen printing; 12-secondary screen printing; 14-an object to be printed; 101-mesh cloth; 121-mesh cloth; a 103-Bus bar pattern; 1031-Bus bar electrode; 123-Finger line pattern 1231-Finger line electrode; 20-a first printing screen; 22-a second printing screen; 201-a first frame; 203-a first mesh fabric; 205-a first polymer material layer; 207-finger electrode pattern; 209-part; 2071-recess; 221-a second frame; 223-a second mesh; 225-a second polymer material layer; 227-monolithic electrode pattern; 229-protrusions; 60-a monolithic electrode; 601-an electrode recess; 70-finger electrodes; 701-left/right; s10 — a first rake face; s12-first pasting printing surface; s20-a second rake face; s22-second pasting printing surface; h1 — first height; h2-second height H3-third height; h4-fourth height; h5-height; h7-height; h6-depth; l1-first length; l2-second length; w1-monolithic electrode width; l4-fourth length.

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 detail with reference to the accompanying drawings and specific embodiments.

The embodiment of the invention provides a secondary printing screen structure and a method for printing a solar cell, aiming at the problem of improving the power generation efficiency of the solar cell in the prior art. Fig. 5 is a schematic view illustrating a printing screen structure for secondary printing according to an embodiment of the present invention; FIG. 7 is a schematic view illustrating the cross-sectional structure A-A of FIG. 5 and increasing the relationship between the cross-sectional structure A-A and the object to be printed. Referring to fig. 5 and 7, in an embodiment of the present invention, a secondary printing screen structure for printing a solar cell includes a first printing screen 20. It should be appreciated that in one embodiment of the present invention, the full-sheet electrode pattern is printed using a prior art printing screen structure, and then the finger electrodes are printed by the first printing screen 20 of the present invention.

The first printing screen 20 includes a first frame 201, a first mesh 203, and a first polymer material layer 205. The first mesh 203 is stretched and fixed on the first frame 201, and the first mesh 203 includes a first scraping surface S10 and a first printing surface S12, the first polymer material layer 205 wraps the first mesh 203, and the second polymer material layer 205 includes a plurality of finger-like electrode patterns 207, wherein the left and/or right sides of the finger-like electrode patterns 207 include a plurality of concave portions 2071 on one side of the first printing surface S12, and the concave portions 2071 are located on the left and/or right sides of the finger-like electrode patterns 207. In addition, the first mesh 203 is reserved with a portion 209 contacting with a plurality of integral electrodes on a to-be-printed object.

On the other hand, as shown in fig. 5, not every finger electrode pattern 207 has its left side and right side contacting the portion 209, for example, the finger electrode pattern 207 on the right side of the first printing screen 20 contacts the full-scale electrode pattern 207 through its left side, the finger electrode pattern 207 on the left side of the first printing screen 20 contacts the full-scale electrode pattern 207 through its right side, and the finger electrode pattern 207 in the middle of the first printing screen 20 contacts the full-scale electrode pattern 207 through its left side and right side simultaneously. Accordingly, the finger electrode pattern 207 includes a recess 2071 on the left and/or right side.

Furthermore, as shown in fig. 7, the object to be printed 14 and the integral electrode 60 printed on the object to be printed 14, the integral electrode 60 has an integral electrode width W1, and the integral electrode 60 is embedded into the portion 209 during printing, so that the finger-shaped electrode can be directly printed on the integral electrode 60. In addition, each of the finger electrode patterns 207 includes a first length L1 and a first height H1, the recess 2071 includes a second length L2 and a second height H2, and the second length L2 may be any value in the range of 1/3 to 1/10 of the full-sheet electrode width W1, i.e., the finger electrode may contact the full-sheet electrode 60 through the protruding portion of the second length L2. It should be appreciated that although a few of the finger electrode patterns 207 are shown in FIG. 5 as having different lengths, such as the finger electrode patterns 207 located at the four corners of the second mesh 203, a majority of the finger electrode patterns 207 are illustrated primarily in the present invention.

Fig. 12 is a schematic view illustrating a part of a to-be-printed object after being printed by the printing screen structure according to an embodiment of the present invention; fig. 13 is a schematic side view illustrating a part of a to-be-printed object after being printed by the printing screen structure according to an embodiment of the present invention. Referring to fig. 5, 7, 12 and 13, in an embodiment of the present invention, after printing on the object 14 by using the prior art printing screen, a monolithic electrode 60 is formed on the object 14. After printing the monolithic electrode 60 on the object 14, the first printing screen 20 of the embodiment of the invention is used again to print on the object 14, and the portion 209 is aligned with the monolithic electrode 60 to form the finger electrode 70 on the object 14, and the finger electrode 70 is tightly combined with the monolithic electrode 60 through the half-cut left side 701 or the half-cut right side 701. In this way, when the first printing screen 20 is used for printing, the finger electrodes 70 can be directly bonded to the monolithic electrode 60, and a gap is not easily generated between the finger electrodes 70 and the monolithic electrode 60, so that the conductivity is increased, the monolithic electrode 60 and the finger electrodes 70 can have a better contact effect, and the height fluctuation between the two electrodes is not too large, thereby improving the power generation efficiency of the solar cell.

On the other hand, in another embodiment of the present invention, a printing screen for printing a full-sheet electrode can be structurally improved. Fig. 6 is a schematic view illustrating a printing screen structure for one-time printing according to another embodiment of the present invention; fig. 8 is a schematic view illustrating the cross-sectional structure a-a of fig. 6. Referring to fig. 6 and 8, in another embodiment of the present invention, the secondary printing screen structure for printing the solar cell further includes a second printing screen 22, and the second printing screen 22 includes a second frame 221, a second mesh cloth 223 and a second polymer material layer 225. The second mesh cloth 223 is stretched and fixed on the second frame 221, and the second mesh cloth 223 includes a second scraping surface S20 and a second pasting surface S22, the second polymer material layer 225 covers the second mesh cloth 223, and the second polymer material layer 225 includes a plurality of whole-sheet electrode patterns 227, wherein the whole-sheet electrode patterns 227 include a plurality of protrusions 229 on one side of the second pasting surface S22, and the protrusions 229 are located on the left and right sides of the whole-sheet electrode patterns 227.

Furthermore, the full-sheet electrode pattern 227 comprises a third height H3 and a full-sheet electrode width W1, and the protrusions 229 comprise a fourth height H4 and a fourth length L4, wherein in another embodiment of the present invention, the fourth height H4 may be any value within a range of 5 to 30 μm, and the fourth length L4 may be any value within a range of 1/3 to 1/10 of the full-sheet electrode width W1.

It should be understood that, in the above embodiments of the present invention, the first mesh 203 and the second mesh 223 may be both meshes of a single material, while in other embodiments of the present invention, the first mesh 203 and the second mesh 223 may be a composite mesh, i.e., the first mesh 203 and the second mesh 223 may be composed of two materials, for example, the first mesh 203 comprises a teflon material and a metal mesh material, and the finger-shaped electrode pattern 207 and the whole-piece electrode pattern 227 are formed on the metal mesh material.

Fig. 14 is a schematic view illustrating a part of a to-be-printed object after being printed by the printing screen structure according to another embodiment of the present invention; fig. 15 is a schematic side view illustrating a part of an object to be printed after being printed by the printing screen structure according to another embodiment of the present invention. As shown in fig. 5 to 8, 14 and 15, in another embodiment of the present invention, after the second printing screen 22 is used to print on the object 14 to be printed, the whole-piece electrode 60 is formed on the object 14 to be printed, and an electrode recess 601 is formed on each of the left and right sides of the whole-piece electrode 60. After the printing of the monolithic electrode 60 on the object to be printed 14 is completed, the first printing screen 20 is used again to print on the object to be printed 14, so as to form the finger electrode 70 on the object to be printed 14, and the finger electrode 70 can be embedded into the electrode recess 601 of the monolithic electrode 60. In this way, when the first printing screen 20 is used for printing, the finger electrodes 70 can be directly embedded in the electrode recesses 601 and are less likely to collide with the monolithic electrodes 60, and the monolithic electrodes 60 and the finger electrodes 70 can have better contact effect, and the height fluctuation between the two electrodes is not too large, thereby further improving the power generation efficiency of the solar cell.

Fig. 9 is a flowchart for explaining a method of fabricating a secondary printing screen structure for printing a solar cell according to still another embodiment of the present invention. As shown in fig. 5, 7 and 9, the method for manufacturing a secondary printing screen structure for printing a solar cell according to the present invention includes steps S101 to S105, where the step S101 is: coating and forming a first polymer material layer 205 on a first mesh 203 of a first printing screen 20, wherein the first mesh 203 includes a first scraping surface S10 and a first pasting surface S12; step S103 is: forming a plurality of finger electrode patterns 207 on a side of the first polymer material layer 205 on the first printing surface S12 by an etching process; and step S105 is: on one side of the first polymer material layer 205 on the first pasting surface S12, a plurality of concave portions 2071 are formed on the left and/or right side of each of the finger electrode patterns 207 by the etching process.

On the other hand, each of the finger electrode patterns 207 includes a first length L1 and a first height H1, the recess 2071 includes a second length L2 and a second height H2, and the second length L2 may be any value in the range of 1/3 to 1/10 of the full-sheet electrode width W1. In addition, the etching process is a laser etching process.

Further, fig. 10 is a flowchart for explaining a method of manufacturing a secondary printing screen structure for printing a solar cell according to still another embodiment of the present invention. Referring to fig. 6, 8 and 10, in another embodiment of the present invention, the method for manufacturing a secondary printing screen structure for printing a solar cell further includes steps S107 to S111. Step S107 is: coating and forming a second polymer material layer 225 on a second mesh cloth 223 of a second printing screen 22, wherein the second mesh cloth 223 includes a second scraping surface S20 and a second pasting surface S22; step S109 is: forming a plurality of monolithic electrode patterns 227 on the second polymer material layer 225 by the etching process; and step S111 is: on one side of the second polymer material layer 225 on the second printing surface S22, a plurality of protrusions 229 are formed on the left and right sides of each of the full-sheet electrode patterns 227 by the etching process.

On the other hand, the one-piece electrode pattern 227 includes a third height H3 and a one-piece electrode width W1, and the protrusions 229 include a fourth height H4 and a fourth length L4, in yet another embodiment of the present invention, the fourth height H4 may be any value within a range of 5 to 30 μm, and the fourth length L4 may be any value within a range of 1/3 to 1/10 of the one-piece electrode width W1.

As can be seen from the above-mentioned manufacturing method, the protrusions 229 and the recesses 2071 of various specifications can be manufactured by the laser etching process in the present invention.

Fig. 11 is a flowchart for describing a secondary printing method using the secondary printing screen structure according to another embodiment of the present invention. Referring to fig. 5 to 13, a secondary printing method according to another embodiment of the present invention includes steps S201 and S203, where the step S201 is: the paste penetrates through the whole-piece electrode pattern and forms a plurality of whole-piece electrodes 60 on an object to be printed 14; and step S203 is: the monolithic electrode 60 is aligned by the reserved portion 209, and the paste is made to pass through the finger electrode pattern 207 and the recess 2071 and form a plurality of finger electrodes 70 on the object 14 to be printed, wherein the finger electrodes 227 are bonded to the monolithic electrode 60 by the half-cut left side 701 and/or the half-cut right side 701. It should be appreciated that the half-cut left side 701 and/or the half-cut right side 701 is created by slurry passing through the recess 2071.

In another embodiment of the present invention, the printing screen structure shown in fig. 6 and 8 may be applied to print the monolithic electrodes. For example, as shown in fig. 6, 8, 14 and 15, in a printing method according to another embodiment of the present invention, the slurry can pass through the monolithic electrode pattern 227 and the protrusions 229 and form a plurality of monolithic electrodes 60 on a to-be-printed object 14. Wherein, the left and right sides of each integral electrode 60 respectively comprise an electrode concave 601; the finger electrodes 227 may be further fitted to the electrode recesses 601 of the monolithic electrode 60 via the half-cut left side 701 and/or the half-cut right side 701.

On the other hand, as shown in fig. 12 and 13, among the electrodes printed on the object 14 through the first printing screen 20 and the second printing screen 22, the full-sheet electrode 60 includes a height H5. The half-cut left side 701 and/or the half-cut right side 701 of the finger electrode 70 each have a height H7, and the height H7 may be any value in the range of 5 to 30 μm. In addition, in the electrode structure shown in fig. 14 and 15, the electrode recess 601 of the monolithic electrode 60 includes a depth H6, and the depth H6 is any value in the range of 5 to 30 μm.

In summary, the present invention provides a secondary printing screen structure and a method for printing a solar cell. In the secondary printing screen structure for printing a solar cell and the method for manufacturing the same of the present invention, a finger-shaped electrode pattern including a concave portion may be provided, and a full-sheet electrode pattern including a convex portion may be further provided. On the other hand, the present invention further provides a secondary printing method using the secondary printing screen structure, as is apparent from fig. 4 and 13, compared with the prior art, the two solar electrodes printed by the secondary printing screen structure of the present invention have no large fluctuation, and the whole sheet type electrode 60 and the finger type electrode 70 have a better contact effect, thereby improving the power generation efficiency of the solar cell.

While the preferred embodiments of the present invention have been described, 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 as defined in the following claims.