KR20150084517A - Solar cell - Google Patents

Abstract

The present invention relates to a solar cell, including a semiconductor substrate which forms a p-n connection; a first electrode and a second electrode which are located at a different position on the rear surface of the semiconductor substrate; a first auxiliary electrode which is located on the rear surface of the semiconductor and is connected to the first electrodes; and a second auxiliary electrode which is located at a different position of the first auxiliary electrode on the rear surface of the semiconductor where the first electrodes are installed at a different position in a first direction, the second electrode are installed at a different position in a first direction, and the first electrodes arranged in the first direction are located at a different position of the second electrode in the second direction crossed with the first direction.

Description

Solar cell {SOLAR CELL}

The present invention relates to a solar cell.

A typical solar cell has a substrate made of different conductivity type semiconductors, such as p-type and n-type, an emitter, and an electrode connected to the substrate and the emitter, respectively. At this time, a p-n junction is formed at the interface between the substrate and the emitter.

Particularly, research and development on a back electrode type solar cell having an n-electrode and a p-electrode formed only on the back surface of a silicon substrate without forming an electrode on the light receiving surface of a silicon substrate for increasing the efficiency of the solar cell is underway. A modularization technique of connecting a plurality of such back electrode type solar cell cells and electrically connecting them is also in progress.

The module and the technique are typical of a method of electrically connecting a plurality of solar cells with a metal interconnection, and a method of electrically connecting a plurality of solar cells with a metal interconnection using a wiring board on which wiring is previously formed.

The object of the present invention is to provide a solar cell.

A solar cell according to the present invention includes: a semiconductor substrate on which a p-n junction is formed; A first electrode and a second electrode disposed on a rear surface of the semiconductor substrate so as to be spaced apart from each other; A first auxiliary electrode disposed on a rear surface of the semiconductor substrate and connected to the plurality of first electrodes; And a second auxiliary electrode spaced apart from the first auxiliary electrode on the rear surface of the semiconductor substrate and connected to the plurality of second electrodes, wherein the first electrodes are arranged in a plurality of locations spaced apart from each other in the first direction, A plurality of first electrodes arranged in a first direction and a plurality of second electrodes arranged in a first direction are arranged in a second direction intersecting with the first direction, It is separated.

Here, the plurality of first and second electrodes may be provided in a dot shape, and the planar shape of each dot in the plurality of first and second electrodes may be at least one of a rectangle, an ellipse, and a circle.

In the first embodiment, the rear surface of the semiconductor substrate is divided into a first substrate region and a second substrate region in which a boundary line is formed in the second direction, the first auxiliary electrode is disposed on the first substrate region, The electrode may be disposed over the second substrate region.

Here, each of the first and second auxiliary electrodes may be formed as a tubular electrode having a plurality of first and second opening holes, wherein the first and second auxiliary electrodes have a plurality of first aperture holes And the positions of the plurality of second opening holes provided in the second auxiliary electrode in the second substrate region overlap with the positions of at least the plurality of second electrodes.

Further, in the first substrate region, the first electrode and the first auxiliary electrode are connected to each other by an electrode adhesive of a conductive material, and the second electrode and the second auxiliary electrode in the second substrate region are connected to each other by an electrode adhesive .

Here, the first auxiliary electrode may be connected to the first electrode by filling the plurality of first opening holes with the electrode adhesive, and the second auxiliary electrode may be connected to the second electrode by filling the plurality of second opening holes with the electrode adhesive.

An insulating layer of an insulating material is formed between the second electrode and the first auxiliary electrode and between the second electrode and the first electrode in the first substrate region and between the first electrode and the second auxiliary electrode in the second substrate region, And an insulating layer may be formed between the first electrode and the second electrode.

The second embodiment may further include an insulating adhesive layer having a plurality of opening holes formed in the rear surface of the semiconductor substrate so as to overlap the positions of the plurality of first and second electrodes, The size of the planar area of each of the opening holes may be larger than the planar size of each of the first and second electrodes.

As a result, a plurality of first and second electrodes can be positioned in the plurality of opening holes formed in the insulating adhesive layer, and the first and second auxiliary electrodes can be disposed on the insulating adhesive layer.

The first auxiliary electrode is connected to the plurality of first electrodes and includes a plurality of first connecting portions extending in the first direction and a first pad portion connected to the ends of the plurality of first connecting portions and extending in the second direction And the second auxiliary electrode is connected to the plurality of second electrodes and includes a plurality of second connection portions extending in the first direction and a second pad portion connected to the ends of the plurality of second connection portions and extending in the second direction can do.

At this time, each of the plurality of first and second connection portions may be located in an area where the plurality of opening holes are not formed in the insulating adhesive layer.

Further, the first electrode and the first connection portion are connected to each other by an electrode adhesive of a conductive material, the second electrode and the second connection portion are connected to each other by an electrode adhesive, and between the first electrode and the second connection portion, An insulating layer made of an insulating material may be formed between the electrode and the first connection portion.

As described above, the solar cell according to the present invention further includes additional first and second auxiliary electrodes in addition to the first and second electrodes to further reduce the resistance of the electrode. The first and second electrodes are provided in a dot shape, It is possible to further reduce the banding.

FIGS. 1 to 5B illustrate a solar cell according to a first embodiment of the present invention.
FIG. 6 is a view for explaining an example of a method of manufacturing a solar cell according to the first embodiment shown in FIGS. 1 to 5B.
FIGS. 7 to 11 are views for explaining a solar cell according to a second embodiment of the present invention.
FIG. 12 is a view for explaining an example of a method of manufacturing a solar cell according to the second embodiment described in FIGS. 7 to 11. FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention in the drawings, portions not related to the description are omitted, and like reference numerals are given to similar portions throughout the specification.

Hereinafter, the front surface may be a surface of a solar cell to which direct light is incident, and the rear surface may be a surface opposite to a solar cell in which direct light is not incident, or reflected light other than direct light may be incident.

Hereinafter, a solar cell according to an embodiment of the present invention will be described with reference to the accompanying drawings.

FIGS. 1 to 5B illustrate a solar cell according to a first embodiment of the present invention.

1 is a perspective view of a solar cell according to a first embodiment of the present invention. FIG. 2A is a cross-sectional view illustrating a back surface pattern of a semiconductor substrate 110 in which first and second auxiliary electrodes P141 and P142 are removed in FIG. FIG. 2B is a pattern in which an insulating layer IL is formed on the rear surface of the semiconductor substrate 110 in FIG. 2A, and FIGS. 3A and 3B are patterns of first and second 3A and 3B illustrate a state in which the first and second auxiliary electrodes P141 and P142 shown in FIG. 3A are disposed on the rear surface of the semiconductor substrate 110. FIGS. 3A and 3B are views for explaining the electrodes P141 and P142, 4A and 4B are diagrams for explaining a state in which the first and second auxiliary electrodes P141 and P142 are connected to the rear surface of the semiconductor substrate 110. FIG.5A shows a cross section of the line 5A-5A in FIG.4 And Fig. 5B is a cross-sectional view taken along the line 5b-5b in Fig.

1 to 5B, a solar cell according to a first embodiment of the present invention includes a semiconductor substrate 110, a semiconductor substrate 110 formed on one surface thereof, and a pn junction formed between the semiconductor substrate 110 and the semiconductor substrate 110 A plurality of first and second electrodes C141 and C142 spaced apart from each other on the rear surface of the semiconductor substrate 110, A first auxiliary electrode P141 disposed on the rear surface of the semiconductor substrate 110 and connected to the plurality of first electrodes C141 and a first auxiliary electrode P141 disposed on the rear surface of the semiconductor substrate 110, And a second auxiliary electrode P142 connected to the plurality of second electrodes C142.

Although not shown in FIGS. 1 to 5B, the solar cell according to the present invention may further include an antireflection film (not shown) for minimizing the reflection of light incident on the front surface of the semiconductor substrate 110.

1, the solar cell according to the first embodiment includes a first auxiliary electrode P141 having a plurality of first opening holes H1 formed on a rear surface of a semiconductor substrate 110, And a second auxiliary electrode P142 formed with an opening hole H2 may be connected.

Here, the semiconductor substrate 110 is a semiconductor substrate 110 that forms a p-n junction. More specifically, the semiconductor substrate 110 may be a semiconductor substrate 110 of a first conductivity type, for example, n-type conductivity type silicon. The semiconductor substrate 110 may be formed by doping a first conductivity type impurity into a wafer formed of a silicon material.

In addition, a plurality of emitter portions 121 and a plurality of rear electric fields 172 may be formed on the rear surface of the semiconductor substrate 110, as shown in FIG. 2A.

Specifically, as shown in FIG. 2A, each of the emitter portions 121 may be spaced apart from each other on the rear surface of the semiconductor substrate 110, and may extend in a first direction x in parallel with each other. The plurality of emitter sections 121 may be formed by doping a second conductivity type, for example, a p-type impurity opposite to the conductivity type of the semiconductor substrate 110 . Accordingly, the emitter 121 and the semiconductor substrate 110 can form a p-n junction.

The plurality of emitter portions 121 may be spaced apart from each other in a plurality of positions in the back surface of the semiconductor substrate 110. The plurality of emitter portions 121 may be formed in the same direction as the plurality of emitter portions 121, (x). < / RTI > Therefore, as shown in FIG. 2A, a plurality of emitter portions 121 and a plurality of rear electric sections 172 may be alternately arranged on the rear surface of the semiconductor substrate 110. [

The plurality of rear electric fields 172 are impurities, for example, n ++ parts, which contain impurities of the same conductivity type as that of the semiconductor substrate 110 at a higher concentration than the semiconductor substrate 110.

The first electrode C141 may be physically and electrically connected to the emitter section 121 and may be formed on the rear surface of the semiconductor substrate 110 along the emitter section 121. [

The second electrode C142 is physically and electrically connected to the semiconductor substrate 110 through the rear electric part 172 and is formed on the rear surface of the semiconductor substrate 110 along the plurality of rear electric parts 172 .

The first electrodes C141 may be arranged in a plurality of dots spaced apart from each other by a distance DC1x in the first direction x on the rear surface of the semiconductor substrate 110 along the emitter layer 121. [ At this time, the first electrode C141 may be arranged in a dot shape along the plurality of lines C1L1 and C1L2 as shown in Fig. 2A on one emitter section 121 extending in the first direction x , But may be formed along one line as shown. For example, it is also possible to omit the dot-shaped first electrode C141 arranged along the C1L2 line.

The second electrodes C142 may be arranged in the form of a plurality of dots spaced apart from each other by DC2x in the first direction x on the rear surface of the semiconductor substrate 110 along the rear electric field portion 172. [ At this time, the second electrode C142 may also be arranged in a dot shape along the plurality of lines C2L1 and C2L2 as shown in FIG. 2A on one rear electric line 172 extending in the first direction x However, it is also possible to form along one line as shown. For example, it is also possible to omit the second electrode C142 in the form of a dot arranged along the C2L2 line.

The plurality of first electrodes C141 arranged in the first direction x and the plurality of second electrodes C142 arranged in the first direction x are arranged in the first direction x, And can be disposed apart from each other by DCy in two directions (y).

Here, the planar shape of each dot in the plurality of first and second electrodes C141 and C142 may be at least one of a rectangle, an ellipse, and a circle.

2A, the rear surface of the semiconductor substrate 110 having the plurality of first and second electrodes C141 and C142 is divided into the first and second electrodes C141 and C142, 1, the first auxiliary electrode P141 may be disposed on the first substrate region AP1 and the second auxiliary electrode P141 may be disposed on the second substrate region AP1, The electrode P142 may be disposed on the second substrate region AP2.

2B, the insulating layer IL may be formed on the rear surface of the semiconductor substrate 110 having the plurality of first and second electrodes C141 and C142.

More specifically, the insulating layer IL is formed on the rear surface of the semiconductor substrate 110 so as to cover the plurality of second electrodes C142 and the rear electric section 172 in the first substrate region AP1, In the second substrate region AP2, a plurality of first electrodes C141 and an emitter portion 121 may be formed so as to cover the first electrode C141.

As the material of the insulating layer IL, for example, a thermosetting insulating resin such as an epoxy may be used. The insulating layer IL prevents the plurality of first electrodes C141 and the second auxiliary electrode P142 from shorting to each other or the plurality of second electrodes C142 and the first auxiliary electrode P141 from being short- Can play a role.

3A, the first and second auxiliary electrodes P141 and P142 are formed on the rear surface of the semiconductor substrate 110 in a state where the insulating layer IL is coated on the rear surface of the semiconductor substrate 110. Thus, 1 and 2 substrate regions AP1 and AP2, respectively.

3A, each of the first and second auxiliary electrodes P141 and P142 may be formed as a tubular electrode having a plurality of first and second opening holes H1 and H2.

More specifically, each of the first auxiliary electrodes P141 may be provided with a plurality of first opening holes H1 that are spaced apart from each other in the first direction x and the second direction y, P142 may be provided with a plurality of second opening holes H2 spaced apart from each other in the first direction x and the second direction y.

The pattern of each of the first and second aperture holes H1 and H2 provided in the first and second auxiliary electrodes P141 and P142 may be a pattern of the first and second electrodes C141 and C142 . ≪ / RTI > Therefore, the positions of each of the first and second opening holes H1 and H2 may overlap with the positions of the first and second electrodes C141 and C142, respectively.

Therefore, the spacing DP1x in the first direction x and the spacing DP2x in the plurality of second opening holes H2 in the first direction x from the first opening H1 are And the separation distances DP1x and DP2x of the first and second aperture holes H1 and H2 in the first direction x can be the same as the distances DP1x and DP2x of the first and second electrodes C141 and C142, May be equal to the spacing distance (DC1x, DC2x) in the first direction (x).

3A, each of the first and second auxiliary electrodes P141 and P142 may include a first substrate region AP1 and a second substrate region AP1 on the rear surface of the semiconductor substrate 110, AP2).

The positions of the plurality of first opening holes H1 provided in the first auxiliary electrode P141 in the first substrate region AP1 overlap with the positions of the plurality of first and second electrodes C141 and C142 And the positions of the plurality of second opening holes H2 provided in the second auxiliary electrode P142 in the second substrate region AP2 overlap with the positions of the plurality of first and second electrodes C141 and C142 .

Accordingly, a plurality of first electrodes C141 may be positioned in the plurality of first opening holes H1, and a plurality of second electrodes C142 may be positioned in the plurality of second opening holes H2 .

Since the insulating layer IL is formed on the rear surface of the semiconductor substrate 110 as shown in FIG. 2B, the first auxiliary electrode P141 and the second auxiliary electrode C142 in the first substrate region AP1 And the second auxiliary electrode P142 and the first electrode C141 in the second substrate region AP2 may be insulated by the insulating layer IL.

4 to 5B, in the first substrate region AP1, the insulating layer IL is exposed through the plurality of first opening holes H1, which are overlapped with the second electrode C142, In the second substrate region AP2, the insulating layer IL may be exposed through the plurality of second opening holes H2 overlapping the first electrode C141.

4, a plurality of first electrodes C141 may be exposed through a plurality of first opening holes H1 in the first substrate region AP1, a plurality of first electrodes C141 may be exposed through the plurality of first opening holes H1, The plurality of second electrodes C142 may be exposed through the plurality of second opening holes H2.

As described above, the electrode adhesive (ECA) of a conductive material is applied to the plurality of first and second opening holes (H1, H2) in which the plurality of first and second electrodes (C141, C142) The first electrode C141 and the first auxiliary electrode P141 and the plurality of second electrodes C142 and the second auxiliary electrode P142 may be connected to each other.

As described above, the first and second openings H1 and H2 in which the plurality of first and second electrodes C141 and C142 are exposed are filled with the electrode adhesive ECA to form the first and second electrodes C141 and C142, And the first and second auxiliary electrodes P141 and P142 are connected to each other as shown in FIGS. 5A and 5B.

5A, the first electrode C141 and the first auxiliary electrode P141 may be connected to each other by filling the first opening hole H1 with an electrode adhesive ECA, C142 and the second auxiliary electrode P142 may be connected to each other by filling the opening hole with an electrode adhesive (ECA), as shown in Fig. 5B.

Here, as the electrode adhesive (ECA), a conductive material such as a solder paste or a conductive paste may be used.

In the first embodiment, a plurality of first opening holes H1 provided in the first auxiliary electrode P141 are not limited to the plurality of first electrodes C141 located in the first substrate region AP1, A plurality of first opening holes H1 are formed at positions overlapping the plurality of second electrodes C142 in the first auxiliary electrode P141, .

The plurality of second openings H2 provided in the second auxiliary electrode P142 may include not only the plurality of first electrodes C141 located in the second substrate region AP2 but also the plurality of second electrodes C142, The second auxiliary electrode P142 may not have a plurality of second opening holes H2 formed at positions overlapping the plurality of first electrodes C141.

However, when a plurality of first and second opening holes H1 and H2 are formed as in the first embodiment, the number of the opening holes is relatively large, so that the coefficient of thermal expansion of the first and second auxiliary electrodes P141 and P142 is reduced .

A method of manufacturing the solar cell according to the first embodiment is as follows.

FIG. 6 is a view for explaining an example of a method of manufacturing a solar cell according to the first embodiment shown in FIGS. 1 to 5B.

The manufacturing method of the solar cell according to the first embodiment of the present invention may be the same as the flowchart shown in Fig. However, this is an example and is not necessarily limited thereto.

As shown in FIG. 6, first, a plurality of second electrodes (not shown) disposed in the first substrate region AP1 of the rear surface of the semiconductor substrate 110 provided with the first and second electrodes C141 and C142 in the dot- A paste for forming the insulating layer IL on the plurality of first electrodes C141 located on the second substrate region C142 and on the second substrate region AP2 may be applied as shown in FIG.

The first and second auxiliary electrodes P141 and P142 described in FIG. 3A may be arranged on the first and second substrate regions AP1 and AP2 as shown in FIG. 3B (S2).

Next, in the state where the first and second auxiliary electrodes P141 and P142 are arranged as shown in FIG. 4, the first and second openings H1 and H2, in which the first and second electrodes C141 and C142 are exposed, (ECA) can be applied.

Thereafter, the paste for forming the insulating layer IL and the paste for forming the electrode adhesive (ECA) are each cured by heat treatment to form the first and second electrodes C141 and C142 respectively on the first and second auxiliary electrodes P141 , And P142, respectively.

Here, the heat treatment may be performed between steps S1 and S2. In such a case, the paste for forming the insulating layer IL may be cured in advance after step S1.

As described above, the solar cell according to the first embodiment of the present invention further includes additional first and second auxiliary electrodes P141 and P142 in addition to the first and second electrodes C141 and C142, .

The solar cell according to the first embodiment of the present invention includes first and second auxiliary electrodes P141 and P142 in a state where first and second electrodes C141 and C142 are formed in a dot shape on the rear surface of the semiconductor substrate 110, It is possible to arrange the first and second electrodes C141 and C142 while confirming the positions of the first and second openings H1 and H2 provided in the first and second openings H1 and H2.

In addition, the solar cell according to the first embodiment of the present invention has a structure in which the first and second electrodes C141 and C142 are provided in the form of a plurality of dots on the rear surface of the semiconductor substrate 110, In the heat treatment process for connecting the first and second auxiliary electrodes P141 and P142, due to the difference in thermal expansion coefficient between the semiconductor substrate 110 and the first and second electrodes C141 and C142, Can be further reduced. Accordingly, the thermal expansion stress of the semiconductor substrate 110 can be further reduced.

At this time, the plurality of first and second opening holes H1 and H2 on the first and second auxiliary electrodes P141 and P142 serve to reduce the thermal expansion rate of the first and second auxiliary electrodes P141 and P142 themselves The thermal expansion stress of the semiconductor substrate 110 can be further reduced.

The structure and the method of forming the first and second auxiliary electrodes P141 and P142 on the rear surface of the semiconductor substrate 110 in which the first and second electrodes C141 and C142 are provided in a plurality of dot- It can be done in other ways as well.

FIGS. 7 to 11 are views for explaining a solar cell according to a second embodiment of the present invention.

8 is a view for explaining the structure of the semiconductor substrate 110 shown in FIG. 7 and the insulating adhesive layer (IAL), and FIG. 9 is a cross-sectional view of the solar cell according to the second embodiment. 8 is a view for explaining a state in which the first and second electrodes C141 and C142 are disposed on the rear surface of the semiconductor substrate 110 on which the insulating adhesive layer IAL shown in FIG. 11A and 11B illustrate a state in which an electrode adhesive ECA and an insulating layer IL are further formed on the rear surface of the semiconductor substrate 110 on which the first and second electrodes C141 and C142 are disposed. 11 is a diagram for explaining a cross section along a line.

In the following description of FIG. 7, the description of the same parts as those of FIGS. 1 to 6 will be omitted.

7, the solar cell according to the second embodiment of the present invention includes a semiconductor substrate 110, an emitter section 121, a rear electric section 172, first and second electrodes C141 and C142, First and second auxiliary electrodes P141 and P142, and may further include an insulating adhesive layer (IAL).

The semiconductor substrate 110, the emitter section 121 and the rear electric section 172 are the same as those described in the first embodiment. The first and second electrodes C141 and C142 are formed on the rear surface of the semiconductor substrate 110 And the first and second auxiliary electrodes P141 and P142 may be disposed on the rear surface of the semiconductor substrate 110 and connected to the first and second electrodes C141 and C142, .

Here, each of the first and second electrodes C141 and C142 may be configured as described with reference to FIG. 2A. However, as shown in FIGS. 7 and 8, the first electrode C141 may be formed in the first direction x The second electrodes C142 may be arranged in a plurality of dots spaced apart from each other by a distance of DC1 along one C1L line and the second electrodes C142 may be arranged in a first direction x along a single C2L line, And may be arranged in a dot shape. Here, the DC1 interval and the DC2 interval may be the same or different from each other.

A plurality of first electrodes C141 arranged in a first direction x and a plurality of second electrodes C142 arranged in a first direction x are arranged in a second direction X intersecting with the first direction x, (y) by DCy.

Here, the planar shape of each dot in the plurality of first and second electrodes C141 and C142 may be at least one of a rectangle, an ellipse, and a circle.

8, the insulating adhesive layer IAL is disposed on the rear surface of the semiconductor substrate 110. As shown in FIG. 7, the first and second auxiliary electrodes P141 and P142 are electrically insulated The insulating adhesive layer IAL may be disposed between the semiconductor substrate 110 and the first auxiliary electrode P141 and between the semiconductor substrate 110 and the second auxiliary electrode P142.

The insulating adhesive layer (IAL) may be formed of any material having an insulating property. For example, the insulating adhesive layer (IAL) may be formed of a thermosetting resin material such as ethylene vinyl acetate (EVA) have.

In addition, as shown in FIGS. 7 and 8, the insulating adhesive layer IAL may be formed with a plurality of opening holes IH.

The size of each of the opening holes IH may be larger than the planar size of each of the plurality of first and second electrodes C141 and C142 and the position of each of the opening holes IH may be a plurality of first and second May be formed in a portion overlapping the positions of the electrodes (C141, C142).

8, when the insulating adhesive layer IAL is disposed on the rear surface of the semiconductor substrate 110, a plurality of first and second electrodes (not shown) are formed in the plurality of opening holes IH formed in the insulating adhesive layer IAL C141, C142) can be located.

In addition, the first and second auxiliary electrodes P141 and P142 may be located on the region where the plurality of opening holes IH are not formed in the insulating adhesive layer IAL in the form shown in FIG.

9, the first auxiliary electrode P141 may include a plurality of first connecting portions PC141 and a first pad portion PP141, and the second auxiliary electrode P142 may include a plurality of A second connection unit PC 142 and a second pad unit PP142.

Here, the plurality of first connection parts PC141 may be connected to the plurality of first electrodes C141 and may extend apart from each other in the first direction x, and the first pad part PP141 may include a plurality of first May be connected to the end of the connection unit (PC 141) and may extend in the second direction (y).

The plurality of second connection parts PC 142 may be connected to the plurality of second electrodes C142 and may extend apart from each other in the first direction x and the second pad part PP142 may extend from the plurality of second electrodes C142, May be connected to the end of the connection unit (PC 142) and may extend in the second direction (y).

Here, each of the first and second connection portions PC141 and PC142 may be located in an area where the plurality of opening holes IH are not formed in the insulating adhesive layer IAL, as shown in FIG.

As described above, the first and second auxiliary electrodes P141 and P142 disposed on the rear surface of the insulating adhesive layer IAL can be connected to the first and second electrodes C141 and C142 by an electrode adhesive (ECA) of a conductive material have.

10 and 11, the first electrode C141 and the first connection portion PC141 are connected to each other by an electrode adhesive (ECA) made of a conductive material, and the second electrode C142 and the first connection portion And the second connecting portions (PC 142) can be connected to each other by an electrode adhesive (ECA).

10 and 11, the first electrode P141 of the first auxiliary electrode P141 and the first electrode PC141 exposed through the opening HH of the insulating adhesive, An electrode adhesive (ECA) is formed on one side surface and a part of the rear surface of the first electrode C141 so that the first auxiliary electrode P141 and the first electrode C141 can be connected to each other.

An electrode adhesive (not shown) is formed on one side surface and the rear surface of the second electrode C142 exposed through one side of the second connection part PC 142 included in the second auxiliary electrode P142 and the opening hole IH of the insulating adhesive ECA) is formed, and the second auxiliary electrode P142 and the second electrode C142 can be connected to each other.

10 and 11, between the first electrode C141 and the second connection unit PC 142 and between the second electrode C142 and the first connection unit PC141, an insulating layer IL May be formed.

11, the insulating layer IL is formed on the other side of the first auxiliary electrode P141, the side of the electrode adhesive (ECA), the other side of the second electrode (C142) and the rest of the rear surface, So that the first auxiliary electrode P141 and the second electrode C142 can be insulated from each other.

The insulating layer IL is formed on the other side of the second auxiliary electrode P142, the side surface of the electrode adhesive ECA, the other side of the first electrode C141, and the rest of the rear surface, And the first electrode C141 may be insulated from each other.

Here, the materials of the electrode adhesive (ECA) and the insulating layer (IL) are the same as those described in the first embodiment.

The solar cell according to the second embodiment of the present invention having such a structure also has additional first and second auxiliary electrodes P141 and P142 in addition to the first and second electrodes C141 and C142, And the first and second electrodes C141 and C142 are provided in the form of a dot, so that the banding of the semiconductor substrate 110 can be further reduced.

In addition, an insulating adhesive layer (IAL) having a plurality of opening holes (IH) is formed on the back surface of the semiconductor substrate (110) having the first and second electrodes (C141, C142) The first and second auxiliary electrodes P141 and P142 can be disposed while confirming the positions of the first and second electrodes C141 and C142 exposed through the opening hole IH, have.

The manufacturing method of the solar cell according to the second embodiment is one example as follows.

FIG. 12 is a view for explaining an example of a method of manufacturing a solar cell according to the second embodiment described in FIGS. 7 to 11. FIG.

12, an insulating adhesive layer IAL having a plurality of opening holes IH is formed on the rear surface of a semiconductor substrate 110 provided with first and second electrodes C141 and C142 in a dot shape The sheet for alignment can be aligned and aligned as shown in Fig. 8 (S1 ')

Then, the first and second auxiliary electrodes P141 and P142 can be arranged at a position on the sheet on which the opening hole IH is not formed as shown in FIG. 9 (S2 ').

Next, as shown in FIGS. 10 and 11, a paste for forming an electrode adhesive (ECA) is applied so that the first and second electrodes C141 and C142 and the first and second auxiliary electrodes P141 and P142 are electrically connected to each other (S3 '), and a paste for forming the insulating layer (IL) can be applied (S4') to a portion where no paste is formed for forming the electrode adhesive (ECA).

Thereafter, the paste for forming the electrode adhesive (ECA) and the paste for forming the insulating layer (IL) are each cured by performing the heat treatment process so that the first and second electrodes (C141, C142) , And the two auxiliary electrodes P141 and P142 (S5 ').

It will be apparent to those skilled in the art that various modifications, substitutions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. will be. Therefore, the embodiments disclosed in the present invention and the accompanying drawings are intended to illustrate and not to limit the technical spirit of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments and the accompanying drawings . The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

Claims (17)

a semiconductor substrate on which a pn junction is formed;
A first electrode and a second electrode spaced apart from each other on a rear surface of the semiconductor substrate;
A first auxiliary electrode disposed on a rear surface of the semiconductor substrate and connected to the plurality of first electrodes; And
And a second auxiliary electrode disposed on a rear surface of the semiconductor substrate and spaced apart from the first auxiliary electrode and connected to the plurality of second electrodes,
Wherein the first electrodes are arranged in a plurality of locations spaced apart from each other in the first direction,
The second electrodes are arranged in a plurality of locations spaced apart from each other in the first direction,
Wherein the plurality of first electrodes arranged in the first direction and the plurality of second electrodes arranged in the first direction are spaced apart from each other in a second direction intersecting the first direction. The method according to claim 1,
Wherein the plurality of first and second electrodes are provided in a dot shape. 3. The method of claim 2,
Wherein the planar shape of each dot in the plurality of first and second electrodes is at least one of a rectangle, an ellipse, and a circle. The method according to claim 1,
Wherein a rear surface of the semiconductor substrate is divided into a first substrate region and a second substrate region in which a boundary line is formed in the second direction,
Wherein the first auxiliary electrode is disposed on the first substrate region, and the second auxiliary electrode is disposed on the second substrate region. 5. The method of claim 4,
Wherein each of the first and second auxiliary electrodes is formed as a tubular electrode having a plurality of first and second opening holes. 6. The method of claim 5,
Wherein a position of the plurality of first opening holes provided in the first auxiliary electrode in the first substrate region overlaps at least a position of the plurality of first electrodes,
Wherein a position of the plurality of second opening holes provided in the second auxiliary electrode in the second substrate region overlaps at least a position of the plurality of second electrodes. 6. The method of claim 5,
Wherein the first electrode and the first auxiliary electrode are connected to each other by an electrode adhesive of a conductive material in the first substrate region,
And the second electrode and the second auxiliary electrode in the second substrate region are connected to each other by the electrode adhesive. 6. The method of claim 5,
Wherein the first auxiliary electrode is connected to the first electrode by filling the plurality of first opening holes with the electrode adhesive,
And the second auxiliary electrode is filled with the electrode adhesive in the plurality of second opening holes and connected to the second electrode. 6. The method of claim 5,
An insulating layer of an insulating material is formed between the second electrode and the first auxiliary electrode in the first substrate region and between the second electrode and the first electrode,
Wherein the insulating layer is formed between the first electrode and the second auxiliary electrode in the second substrate region, and between the first electrode and the second electrode. The method according to claim 1,
And an insulating adhesive layer on the rear surface of the semiconductor substrate, the insulating adhesive layer having a plurality of opening holes formed in a portion overlapping the positions of the plurality of first and second electrodes. 11. The method of claim 10,
Wherein the planar size of each of the plurality of opening holes formed in the insulating adhesive layer is larger than the planar size of each of the first and second electrodes. 11. The method of claim 10,
Wherein the plurality of first and second electrodes are located in a plurality of opening holes formed in the insulating adhesive layer. 11. The method of claim 10,
Wherein the first and second auxiliary electrodes are disposed on the insulating adhesive layer. 11. The method of claim 10,
The first auxiliary electrode
A plurality of first connection portions connected to the plurality of first electrodes and extending in the first direction,
And a first pad portion connected to an end of the plurality of first connection portions and extending in the second direction,
The second auxiliary electrode
A plurality of second connection portions connected to the plurality of second electrodes and extending in the first direction,
And a second pad portion connected to an end of the plurality of second connection portions and extending in the second direction. 15. The method of claim 14,
Wherein each of the plurality of first and second connection portions is located in a region of the insulating adhesive layer where the plurality of opening holes are not formed. 15. The method of claim 14,
The first electrode and the first connection portion are connected to each other by an electrode adhesive of a conductive material,
And the second electrode and the second connection portion are connected to each other by the electrode adhesive. 15. The method of claim 14,
Wherein an insulating layer of an insulating material is formed between the first electrode and the second connecting portion and between the second electrode and the first connecting portion.

Images