KR20150092607A - Solar cell and solar cell module - Google Patents

Abstract

The present invention relates to a solar cell and a solar cell module. According to the present invention, the solar cell module comprises: a first solar cell and a second solar cell including an insulating member which includes a plurality of first electrodes formed on a rear side of a semiconductor substrate, a plurality of second electrodes formed on the rear side of the semiconductor substrate, a first auxiliary electrode and a first auxiliary electrode pad connected to the first electrodes, and a second auxiliary electrode and a second auxiliary electrode pad connected to the second electrodes; and an interconnector electrically and mutually connected to the first auxiliary electrode pad of the first solar cell and the second auxiliary electrode pad of the second solar cell, or electrically and mutually connected to the second auxiliary electrode pad of the first solar cell and the first auxiliary electrode pad of the second solar cell. A concavity is formed on at least one among a connected side of the first and second auxiliary electrode pads with the interconnector. In addition, according to the present invention, the first auxiliary electrode pad and the second auxiliary electrode pad are connected to the interconnector which connects the solar cells to each other, and the concavity can be formed in a part connected to the interconnector in the first auxiliary electrode pad and the second auxiliary electrode pad.

Description

SOLAR CELL AND SOLAR CELL MODULE [0002]

The present invention relates to a solar cell and a solar cell module.

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 under way.

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.

An object of the present invention is to provide a solar cell and a solar cell module.

A solar cell module according to the present invention includes a plurality of first electrodes formed on a rear surface of a semiconductor substrate, a plurality of second electrodes formed on a rear surface of the semiconductor substrate, a first auxiliary electrode connected to the plurality of first electrodes, A first solar cell and a second solar cell including an insulating member having an electrode pad, a second auxiliary electrode connected to the plurality of second electrodes, and a second auxiliary electrode pad; And the first auxiliary electrode pad of the first solar cell and the second auxiliary electrode pad of the second solar cell or may be electrically connected to the second auxiliary electrode pad of the first solar cell and the first auxiliary electrode pad of the second solar cell, And at least one of the bonding surfaces of the first connector and the second auxiliary electrode pad is provided with concavities and convexities.

That is, concaves and convexes may be formed on at least one of a portion connected to the first and second auxiliary electrode pads in the interconnector and a portion connected to the interconnector in each of the first and second auxiliary electrode pads.

Also, the connection width at which the interconnector and the first auxiliary electrode pad or the interconnector and the second auxiliary electrode pad are connected can be changed as the interconnector extends in the longitudinal direction.

Here, the connection width has the maximum connection width and the minimum connection width, and the maximum connection width and the minimum connection width can be repeated as they progress in the longitudinal direction of the interconnector.

Here, in the portion having the minimum connection width, the interconnector may be spaced apart from the first auxiliary electrode pad or the second auxiliary electrode pad.

At this time, the planar shape in which the interconnector and the first auxiliary electrode pad or the second auxiliary electrode pad are connected may include a curved surface.

The solar cell module includes: a front glass substrate positioned above a front surface of a cell string, the first solar cell and the second solar cell being connected to each other by an interconnector; An upper encapsulant positioned between the front glass substrate and the cell string; A lower encapsulant located on the back side of the cell string; And a back sheet positioned on a rear surface of the lower encapsulant.

Each of the first auxiliary electrode and the second auxiliary electrode extends in a first direction and the first auxiliary electrode pad is connected to an end of the first auxiliary electrode extending in the first direction, And the second auxiliary electrode pad is connected to the end of the second auxiliary electrode extending in the first direction and may extend in the second direction.

At this time, the widths of the first and second auxiliary electrode pads in the first direction may not be uniform.

In addition, the ends of the first auxiliary electrode pad and the second auxiliary electrode pad may each include a curved surface.

The plurality of first auxiliary electrode pads and the plurality of second auxiliary electrode pads may be spaced apart from each other.

In addition, the width of the interconnector may be constant or non-uniform as it proceeds in the second direction.

Further, a solar cell according to the present invention includes: a semiconductor substrate; A plurality of first electrodes formed on a rear surface of a semiconductor substrate; A plurality of second electrodes formed on the rear surface of the semiconductor substrate so as to be spaced apart from and spaced apart from the plurality of first electrodes; A first auxiliary electrode connected to a plurality of first electrodes and a first auxiliary electrode pad connected to an end of the first auxiliary electrode, a second auxiliary electrode connected to the plurality of second electrodes, and a second auxiliary electrode connected to an end of the second auxiliary electrode, Wherein the first auxiliary electrode pad and the second auxiliary electrode pad are connected to an interconnector connecting the plurality of solar cells to each other, and the first auxiliary electrode pad and the second auxiliary electrode pad are connected to each other, At least a portion of the electrode pad connected to the interconnector can be formed with irregularities.

The widths of the first auxiliary electrode pad and the second auxiliary electrode pad may be changed as the lengths of the first auxiliary electrode pad and the second auxiliary electrode pad progress.

Each of the first auxiliary electrode and the second auxiliary electrode extends in a first direction and the first auxiliary electrode pad is connected to an end of a first auxiliary electrode extending in a first direction, And the second auxiliary electrode pad is connected to the end of the second auxiliary electrode extending in the first direction and may extend in the second direction.

In addition, the first auxiliary electrode pad and the second auxiliary electrode pad may have a constant width in the first direction along the second direction.

At this time, the plane shapes of the ends of the first auxiliary electrode pad and the second auxiliary electrode pad may include curved surfaces.

In addition, a plurality of first auxiliary electrode pads and a plurality of second auxiliary electrode pads may be spaced apart from each other, and a plurality of second auxiliary electrode pads may be spaced apart from each other.

As described above, in the solar cell according to the present invention, since the semiconductor substrate and the insulating member are connected to each other to form one integral individual element, when some solar cells are damaged or defective at the time of module formation, can do.

In addition, the solar cell and the solar cell module according to the present invention change the connection width of the inter-connector and the first auxiliary electrode pad or the second auxiliary electrode pad as they move in the longitudinal direction of the inter-connector, The phenomenon that the solar cell is bent by the thermal expansion coefficient between the insulating member and the first auxiliary electrode pad or the second auxiliary electrode pad can be further reduced.

FIGS. 1A and 2B illustrate a solar cell module according to a first embodiment of the present invention.
FIGS. 3 and 4 are views for explaining an example of a solar cell applied to the solar cell module shown in FIG. 1. FIG.
5 is a view for explaining an example of electrode patterns of a semiconductor substrate and an insulating member to be individually connected to each other in the solar cell shown in Figs. 3 and 4. Fig.
6 is a view for explaining a state in which the semiconductor substrate and the insulating member shown in Fig. 5 are connected to each other.
FIG. 7A shows a cross section of the line 7a-7a in FIG.
7B is a cross-sectional view taken along line 7B-7B in FIG.
7C is a cross-sectional view taken along line 7c-7c in FIG. 6. FIG.
8 is a view for explaining a second embodiment of a solar cell module according to the present invention.
FIG. 9 is a view for explaining an insulating member of a solar cell applied to the solar cell module shown in FIG. 8. FIG.
10 is a view for explaining another example of the first auxiliary electrode pad and the second auxiliary electrode pad shown in FIG.
11 to 14 are views for explaining a third embodiment of the solar cell module according to the present invention.
FIG. 15 is a view for explaining the overall cross-sectional structure of the solar cell module according to the first to third embodiments. 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 semiconductor substrate or a front surface of a front glass substrate to which direct light is incident, and the rear surface may be a surface of a semiconductor substrate on which direct light is not incident, The opposite side of one side of the first side.

Hereinafter, a solar cell module according to the present invention and a solar cell applied thereto will be described.

FIGS. 1A and 2B illustrate a solar cell module according to a first embodiment of the present invention.

1A is a cross-sectional view of a solar cell module according to an embodiment of the present invention, in which two solar cells are connected to each other by an interconnector (IC), and FIG. 1B is a cross- And an unevenness is formed on at least one of the bonding surfaces of the electrode pads PP141 and PP142.

2A is a sectional view taken along line 2a-2a in FIG. 1A, and FIG. 2B is a sectional view taken along line 2b-2b in FIG. 1A.

As shown in FIGS. 1A and 2B, a solar cell module according to the present invention includes a first solar cell Cell 1, a semiconductor substrate 110, and an insulating member 200, the first solar cell Cell-a and the second solar cell Cell-b, and the interconnector IC for electrically connecting the first solar cell Cell-a and the second solar cell Cell-b to each other .

Each of the first solar cell Cell-a and the second solar cell Cell-b is a solar cell in which a semiconductor substrate 110 and an insulating member 200 are connected to each other to form one integral individual element. Lt; / RTI >

A plurality of first electrodes C141 and a plurality of second electrodes C142 may be formed on the rear surface of the semiconductor substrate 110. A plurality of first electrodes C141 may be formed on the rear surface of the insulating member 200, The first auxiliary electrode P141 and the first auxiliary electrode pad PP141 to be connected and the second auxiliary electrode P142 and the second auxiliary electrode pad PP142 connected to the plurality of second electrodes C142 are formed .

Here, the first electrode C141 and the first auxiliary electrode P141, and the second electrode C142 and the second auxiliary electrode P142 may be connected by an electrode coupling material ECA of a conductive material.

Each of the first auxiliary electrode P141 and the second auxiliary electrode P142 extends in a first direction x and the first auxiliary electrode pad PP141 extends in a first direction x, And the second auxiliary electrode pad PP142 is connected to the end of the electrode P141 and extends in a second direction y intersecting the first direction x and the second auxiliary electrode pad PP142 extends in the first direction x, May be connected to the end of the electrode P142 and extend in the second direction y. The structure of such a solar cell will be described in detail with reference to Figs. 3 to 7C.

The interconnector (IC) is electrically connected to the first auxiliary electrode pad PP141 of the first solar cell and the second auxiliary electrode pad PP142 of the second solar cell by an interconnect connector (ICA) The second auxiliary electrode pad PP142 of the solar cell and the first auxiliary electrode pad PP141 of the second solar cell may be electrically connected to each other by an interconnection connector ICA.

In such a solar cell module, the solar cell module according to the present invention may have irregularities formed on at least one of the bonding surfaces of the first and second auxiliary electrode pads PP141 and PP142.

As described above, when concave and convex are formed on at least one of the bonding surfaces of the inter-connector (IC) and the first and second auxiliary electrode pads PP141 and PP142, the bonding surface is increased by the unevenness, The protrusions and depressions formed by the irregularities of the first and second auxiliary electrode pads PP141 and PP142 are engaged with each other to improve the adhesion between the inter connector IC and the first and second auxiliary electrode pads PP141 and PP142 .

More specifically, as shown in FIG. 1B, irregularities are formed in a portion of the interconnector (IC) connected to at least the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 At least portions of the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 which are connected to the interconnector IC may have irregularities.

As shown in FIG. 1B, when the concave and convex portions are formed on at least the portions of the interconnector IC, the first auxiliary electrode pad PP141, and the second auxiliary electrode pad PP142 that are connected to each other, The surface area of the portion connected to each other by the ICA is increased and the protrusions and depressions of the irregularities engage with each other so that the adhesion between the interconnector IC and the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 Can be further improved.

At this time, the shape of the irregularities formed in the interconnector (IC), the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP14 is a cross-sectional view in the first direction x, The plurality of protrusions and the plurality of depressions may be repeated, and each of the protrusions and the depressions may be elongated in the second direction y. In addition, The protrusions or depressions may be connected to depressions or protrusions formed on the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142.

Accordingly, it is possible to further strengthen the adhesion in the first direction (x), and during the tableting process for connecting the interconnector (IC), the first auxiliary electrode pad PP141 and the second auxiliary electrode pad Even if the length in the second direction (y) of the flexible printed circuit board (PP) 142 is partially changed, the influence on the adhesive force of the interconnector (IC) can be minimized.

As described above, the concavo-convex structure formed on the bonding surfaces of the interconnector (IC) and the first and second auxiliary electrode pads PP141 and PP142 is not limited to the first embodiment, but also the second and third embodiments As shown in FIG.

Here, the concavo-convex structure formed on the joint surface of the interconnector (IC) can be formed by irradiating the laser beam to the joint surface of the interconnector (IC) and etching the joint surface of the interconnector (IC).

The concavo-convex structure formed on the bonding surfaces of the first and second auxiliary electrode pads PP141 and PP142 may be formed by irradiating a laser beam onto the bonding surfaces of the first and second auxiliary electrode pads PP141 and PP142, The first and second auxiliary electrode pads PP141 and PP142 may be formed as a thin film on the surface of the insulating member 200 in which the concavities and convexities are formed.

1A, the solar cell module according to the present invention has a structure in which the width at which the interconnector IC, the first auxiliary electrode P141 or the interconnector IC and the second auxiliary electrode P142 are connected (Y) of the interconnector (IC).

Here, in the case where the connection width between the interconnection IC and the first auxiliary electrode P141 or the second auxiliary electrode P142 can be changed as it progresses in the longitudinal direction y of the interconnection IC, This can be the case.

(1) In a state in which the widths of the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 are formed to vary along the longitudinal direction y of the interconnection IC, When the interconnection IC is connected to the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142,

(2) The width of the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 along the longitudinal direction (y) of the interconnection IC is uniformly formed, and the width along the longitudinal direction changes When the interconnection IC is connected to the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142,

(3) The case of (1) and the case of (2) are mixed so that the widths of the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 are different from each other in the longitudinal direction y (IC) having a width varying in the longitudinal direction may be connected to the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 in a state where the second auxiliary electrode pad PP141 is formed to be changed in accordance with the width of the second auxiliary electrode pad PP141.

Among the above cases, an example of the case (1) will be described with reference to FIGS. 1A to 10, and an example of the case (2) will be described with reference to FIG. 11 to FIG.

1A, a solar cell module according to the present invention includes a first auxiliary electrode pad PP141 and a second auxiliary electrode pad PP142 in a first direction x, in which an interconnector IC, a first auxiliary electrode pad PP141, and a second auxiliary electrode pad PP142 are connected to each other. (Y), which is the longitudinal direction (y) of the interconnector (IC).

For example, the width at which the interconnection IC and the first auxiliary electrode pad PP141 are connected may be changed between WC1a and WC1b along the longitudinal direction y of the interconnection IC, WC2a and WC2b along the longitudinal direction y of the midship interconnector IC to which the second auxiliary electrode pad PP142 and the second auxiliary electrode pad PP142 are connected to each other.

As described above, in the solar cell module according to the present invention, the width at which the interconnector (IC), the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 are connected is smaller than the width y (IC) is connected to the first solar cell (Cell-a) or the second solar cell (Cell-b) by progressively increasing or decreasing in the second direction The bending of the insulating member 200 can be minimized due to the difference between the thermal expansion coefficient of the insulating member 200 and the thermal expansion coefficient of the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 made of a metallic material have.

That is, when connecting the interconnector (IC) to each solar cell, by changing the connection width along the longitudinal direction (y) of the interconnector (IC), the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 can disperse the length of thermal expansion in the longitudinal direction y of the interconnection IC so that the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 are arranged in the second direction y ) Can be further reduced as a whole.

Accordingly, the thermal stress on the semiconductor substrate 110 integrally attached to the insulating member 200 can be minimized, and damage to the semiconductor substrate 110 can be minimized.

The maximum connection widths WC1a and WC2a of the first interconnection IC and the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 may be 4 mm at maximum and the minimum connection widths WC1b and WC2b may be Unlike in FIG. 2B, it may be 0 mm or not connected. Therefore, the interconnection IC may be spaced apart from the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 at some intervals along the longitudinal direction.

At this time, the maximum connection widths WC1a and WC2a and the minimum connection widths WC1b and WC2b may be repeated as they progress in the second direction y, which is the longitudinal direction of the interconnector IC.

At this time, as shown in FIG. 1A, the planar shape in which the interconnector (IC), the first auxiliary electrode pad PP141, and the second auxiliary electrode pad PP142 are connected may include a curved surface.

At this time, the width WI along the longitudinal direction y of the interconnector IC is constant, and the overlap width of the interconnector IC and the insulating member 200 along the second direction y is constant And the spacing between the interconnector IC and the semiconductor substrate 110 along the second direction y may be constant. Also, as shown in Figs. 1A and 2B, the interconnector IC and the semiconductor substrate 110 may be physically connected to each other.

Hereinafter, an example of a solar cell applied to such a solar cell module will be described in more detail.

FIGS. 3 and 4 are views for explaining an example of a solar cell applied to the solar cell module shown in FIGS. 1A and 1B.

FIG. 3 is an example of a partial perspective view of a solar cell according to an example of the present invention, and FIG. 4 is a sectional view cut along the line 4-4 of the solar cell shown in FIG.

3 and 4, an example of a solar cell according to the present invention includes a semiconductor substrate 110, an antireflection film 130, an emitter section 121, a back surface field (BSF) 172, And may include a plurality of first electrodes C141, a plurality of second electrodes C142, a first auxiliary electrode P141, and a second auxiliary electrode P142.

The antireflection film 130 and the backside electrical conductor 172 may be omitted and may be disposed between the antireflection film 130 and the semiconductor substrate 110 on which the light is incident, (Not shown), which is an impurity portion containing impurities of a higher concentration than that of the semiconductor substrate 110, may be further included.

Hereinafter, as shown in FIGS. 3 and 4, an anti-reflection film 130 and a rear electric conductor 172 are included.

The semiconductor substrate 110 may be a bulk semiconductor substrate 110 made of silicon of a first conductivity type, for example, n-type conductive type. The semiconductor substrate 110 may be formed by doping a first conductivity type impurity into a wafer formed of a silicon material.

The upper surface of the semiconductor substrate 110 is textured to have a textured surface that is an uneven surface. The antireflection film 130 is disposed on the upper surface of the semiconductor substrate 110. The antireflection film 130 may be a single layer or a plurality of layers and may be formed of a hydrogenated silicon nitride film (SiNx: H) or the like. In addition, it is also possible that a front electric part or the like is further formed on the entire surface of the semiconductor substrate 110.

The emitter portions 121 are spaced apart from each other in the rear surface of the semiconductor substrate 110 facing the front surface, and extend in a direction parallel to each other. The plurality of emitter portions 121 may be a second conductive type which is opposite to the conductive type of the semiconductor substrate 110.

The plurality of emitter portions 121 may be formed by doping a p-type impurity of a second conductivity type opposite to the conductivity type of the crystalline silicon semiconductor substrate 110 at a high concentration through a diffusion process.

The plurality of emitter portions 121 may be disposed in the same direction as the plurality of emitter portions 121. The plurality of emitter portions 121 may be spaced apart from each other in a direction parallel to the emitter portions 121, have. Therefore, as shown in FIGS. 3 and 4, a plurality of emitter portions 121 and a plurality of rear electric sections 172 are 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 plurality of rear electric field sections 172 may be formed by doping impurity (n ++) of the same conductivity type as that of the crystalline silicon semiconductor substrate 110 through a diffusion process at a high concentration.

The plurality of first electrodes C141 are physically and electrically connected to the emitter section 121 and extend apart from each other along the emitter section 121. [ The first electrode C141 may extend in the first direction x and the emitter portion 121 may extend in the second direction y when the emitter portion 121 extends in the first direction x. The first electrode C141 may extend in the second direction y.

The plurality of second electrodes C142 are physically and electrically connected to the semiconductor substrate 110 through the rear electric section 172 and extend along the plurality of rear electric sections 172, respectively.

The second electrode C142 may extend in the first direction x and the backside electrical portion 172 may extend in the first direction x when the backside electrical portion 172 extends in the first direction x, y, the second electrode C142 may also extend in the second direction y.

Here, on the rear surface of the semiconductor substrate 110, the first electrode C141 and the second electrode C142 are physically separated from each other and electrically isolated.

The first electrode C141 formed on the emitter section 121 collects charges, for example, holes, which have migrated toward the emitter section 121, and the second electrode C141 formed on the rear electric section 172 C142 may collect electrons, e. G., Electrons, that have migrated toward the backside electrical portion 172. [

The first auxiliary electrode P141 may be electrically connected to the rear surface of the plurality of first electrodes C141. The plurality of first auxiliary electrodes P141 may be formed.

Here, when a plurality of first auxiliary electrodes P141 are formed, the first auxiliary electrodes P141 may be formed in the same direction as the plurality of first electrodes C141, or may be formed in an intersecting direction.

The first auxiliary electrode P141 may be electrically connected to each other at a portion overlapping the first electrode C141.

The second auxiliary electrode P142 may be electrically connected to the rear surface of the plurality of second electrodes C142. The second auxiliary electrode P142 may also be formed as a plurality of second auxiliary electrodes.

Here, when a plurality of second auxiliary electrodes P142 are formed, the second auxiliary electrodes P142 may be formed in the same direction as the plurality of second electrodes C142, or may be formed in an intersecting direction.

The second auxiliary electrode P142 may be electrically connected to each other at a portion overlapping the second electrode C142.

3 and 4 illustrate a plurality of the first auxiliary electrode P141 and the second auxiliary electrode P142 as an example. Alternatively, the first auxiliary electrode P141 and the second auxiliary electrode P142 may be alternatively P142 may be formed as a single sheet electrode.

The first auxiliary electrode P141 and the second auxiliary electrode P142 may be formed of at least one of Cu, Au, Ag, and Al.

The first auxiliary electrode P141 may be electrically connected to the first electrode C141 through an electrically conductive electrode coupling material ECA and the second auxiliary electrode P142 may be electrically connected to the electrode coupling material ECA To the second electrode (C142).

The material of the electrode connection material (ECA) is not particularly limited as long as it is a conductive material. However, a conductive material having a melting point at a relatively low temperature of 130 ° C to 250 ° C is more preferable. For example, Conductive adhesives including metal particles, carbon nanotubes (CNTs), conductive particles including carbon, wires, needles, and the like can be used.

An insulating layer IL for preventing a short circuit may be disposed between the first electrode C141 and the second electrode C142 and between the first auxiliary electrode P141 and the second auxiliary electrode P142 . The insulating layer IL may be an epoxy resin.

3 and 4 show only the case where the first electrode C141 and the first auxiliary electrode P141 are overlapped with each other and the second electrode C142 and the second auxiliary electrode P142 are overlapped with each other, The first electrode C141 and the second auxiliary electrode P142 may overlap each other and the second electrode C142 and the first auxiliary electrode P141 may overlap with each other. In this case, the insulating layer IL may be disposed between the first electrode C141 and the second auxiliary electrode P142 and between the second electrode C142 and the second auxiliary electrode P142 to prevent a short circuit. have.

The first auxiliary electrode P141 and the second auxiliary electrode P142 may be formed by a heat treatment process that applies heat and pressure between 130 ° C and 250 ° C to the electrode connecting material ECA, have.

3 and 4, a first auxiliary electrode pad PP141 for series connection of the solar cells may be electrically connected to the end of the first auxiliary electrode P141, And a second auxiliary electrode pad PP142 for serial connection of the solar cell may be electrically connected to the end of the auxiliary electrode P142. This will be described in detail with reference to FIG.

The insulating member 200 may be disposed on the rear surface of the first auxiliary electrode P141 and the second auxiliary electrode P142.

The melting point of the insulating member 200 is preferably not less than 300 DEG C, more preferably not less than 300 DEG C, more preferably not less than 300 DEG C, As shown in Fig. More specifically, it may be formed of at least one material selected from the group consisting of heat resistant polyimide, epoxy-glass, polyester, and BT (bismaleimide triazine) resin.

Such an insulating member 200 may be formed in the form of a flexible film or in the form of a hard plate rather than a flexible one.

In the solar cell according to the present invention, a first auxiliary electrode P141 and a second auxiliary electrode P142 are formed in advance on the entire surface of the insulating member 200, and a plurality of first electrodes The insulating member 200 and the semiconductor substrate 110 may be connected to each other to form a single discrete element in a state in which the plurality of second electrodes C141 and the plurality of second electrodes C142 are formed in advance.

That is, there may be one semiconductor substrate 110 attached to and connected to one insulating member 200, and one insulating member 200 and one semiconductor substrate 110 are attached to each other to form one integrated type So that one solar cell can be formed.

More specifically, a plurality of (a plurality of) semiconductor elements 110 are formed on the back surface of one semiconductor substrate 110 by a process of attaching one insulating member 200 and one semiconductor substrate 110 to each other, The first electrode C141 and the plurality of second electrodes C142 are attached to the first auxiliary electrode P141 and the second auxiliary electrode P142 formed on the front surface of one insulating member 200 and electrically connected to each other . A more detailed description thereof will be described later.

In the solar cell according to the present invention, the thickness T2 of each of the first auxiliary electrode P141 and the second auxiliary electrode P142 is less than the thickness T1 of each of the first electrode C141 and the second electrode C142 ).

By thus setting the thickness T2 of the first auxiliary electrode P141 and the second auxiliary electrode P142 larger than the thickness T1 of each of the first electrode C141 and the second electrode C142, The process time can be further shortened and thermal stress stress on the substrate can be further reduced than if the first electrode C141 and the second electrode C142 are formed directly on the rear surface of the semiconductor substrate 110, The efficiency of the device can be further improved.

More specifically, it is as follows.

A first electrode C141 connected to the emitter section 172 and a second electrode C141 connected to the rear electric section 172 formed on the rear surface of the semiconductor substrate 110. The emitter section 121, The first electrode C141 and the second electrode C142 may be in direct contact with or very close to the back surface of the semiconductor substrate 110 and may be formed by plating, PVD deposition or a high-temperature heat treatment process.

In this case, the thicknesses of the first electrode C141 and the second electrode C142 should be sufficiently thick in order to secure a sufficiently low resistance between the first electrode C141 and the second electrode C142.

However, when the thicknesses of the first electrode C141 and the second electrode C142 are increased, the thermal expansion coefficient of the first electrode C141 and the second electrode C142 including the conductive metal material is lower than the thermal expansion coefficient of the semiconductor substrate 110 ) Of the thermal expansion coefficient of the heat dissipation member.

Therefore, during the process of forming the first electrode C141 and the second electrode C142 on the rear surface of the semiconductor substrate 110 by a high-temperature heat treatment process, the first electrode C141 and the second electrode C142 contract The semiconductor substrate 110 can not withstand the stress of thermal expansion and thus the possibility of fracture or cracking of the semiconductor substrate 110 is increased and the yield of the solar cell manufacturing process is lowered, The efficiency may be lowered.

In addition, when the first electrode C141 or the second electrode C142 is formed by plating or PVD deposition, the growth rate of the first electrode C141 or the second electrode C142 is very small, Time can be excessive.

However, in the solar cell according to the present invention, the first electrode (C141) and the second electrode (C142) are formed on the rear surface of the semiconductor substrate (110) with a relatively small thickness (T1) The first auxiliary electrode P141 and the second auxiliary electrode P142 formed on the front surface of the first electrode C141 and the second electrode C142 are formed to overlap with each other with a relatively large thickness T2, The insulating member 200 and the one semiconductor substrate 110 can be attached to each other by a heat treatment process in which heat and pressure of 130 to 250 ° C, which is relatively low compared to the ECA, It is possible to prevent cracks or cracks from being generated in the semiconductor substrate 110 and at the same time the resistance of the electrodes formed on the rear surface of the semiconductor substrate 110 can be greatly reduced.

In addition, since the thickness T1 of the first electrode C141 and the second electrode C142 is relatively reduced, the solar cell according to the present invention can minimize the semiconductor manufacturing process time, which is relatively long, The first electrode C141 and the first auxiliary electrode P141 and the second electrode C142 and the second auxiliary electrode P142 can be connected to each other by the heat treatment process of the solar cell, can do.

When the first auxiliary electrode P141 and the second auxiliary electrode P142 are bonded to the first electrode C141 and the second electrode C142 formed on the rear surface of the semiconductor substrate 110, , And helps the process more easily.

That is, the insulating member 200 (200) having the first auxiliary electrode P141 and the second auxiliary electrode P142 formed on the rear surface of the semiconductor substrate 110 in which the first electrode C141 and the second electrode C142 are formed in the semiconductor manufacturing process , The insulating member 200 can facilitate the alignment process and the bonding process more easily.

The holes collected through the first auxiliary electrode P141 and the electrons collected through the second auxiliary electrode P142 in the solar cell according to the present invention manufactured by such a structure are electrically connected to the external device through the external circuit device Can be used.

The operation of the solar cell with the rear-bonding structure is as follows.

When a light is irradiated to the solar cell and is incident on the semiconductor substrate 110 through the antireflection film 130, electron-hole pairs are generated in the semiconductor substrate 110 due to light energy.

These electron-hole pairs are separated from each other by the pn junction of the semiconductor substrate 110 and the emitter section 121, and the holes move toward the plurality of emitter sections 121 having the p-type conductivity type, And are collected by the first auxiliary electrode P141 and the second auxiliary electrode P142, respectively. When the first auxiliary electrode P141 and the second auxiliary electrode P142 are connected by a conductor, a current flows and is used as electric power from the outside.

The case where the semiconductor substrate 110 is the single crystal silicon semiconductor substrate 110 and the emitter portion 121 and the back surface electric portion 172 are formed through the diffusion process has been described as an example.

Alternatively, the heterojunction solar cell in which the emitter layer 121 and the rear electric layer 172 formed of an amorphous silicon material are bonded to the crystalline semiconductor substrate 110, or the emitter layer 121 is formed on the front surface of the semiconductor substrate 110 And is connected to the first electrode C141 formed on the rear surface of the semiconductor substrate 110 through a plurality of via holes formed in the semiconductor substrate 110, the present invention can be similarly applied.

A solar cell having such a structure can connect solar cells adjacent to each other by an interconnect (IC), and thus a plurality of solar cells can be connected in series.

In this structure, a pattern of the first electrode C141 and the second electrode C142 formed on the rear surface of the semiconductor substrate 110 and a pattern of the first auxiliary electrode P141 And the second auxiliary electrode P142 will be described in more detail as follows.

5 is a view for explaining an example of electrode patterns of the semiconductor substrate 110 and the insulating member 200 to be individually connected to each other in the solar cell shown in FIGS. 3 and 4. FIG.

5A is a view for explaining an example of a pattern of the first electrode C141 and the second electrode C142 disposed on the rear surface of the semiconductor substrate 110. FIG 5B is a cross- 5C is a sectional view taken along the line 5 (b) -5 (b) in FIG. 5A. FIG. 5C is a sectional view of the first auxiliary electrode P141 and the second auxiliary electrode P142 disposed on the front surface of the insulating member 200, 5 (d) is a cross-sectional view taken along the line 5 (d) to 5 (d) in FIG. 5 (c).

The front surface of one insulating member 200 as shown in FIGS. 5C and 5D is formed on the rear surface of one semiconductor substrate 110 as shown in FIGS. 5A and 5B, By attaching and connecting, the solar cell according to the present invention can form one integrated discrete element. That is, the insulating member 200 and the semiconductor substrate 110 may be bonded or attached at a ratio of 1: 1.

5A and 5B, a plurality of first electrodes C141 and a plurality of second electrodes C142 are formed on the rear surface of the semiconductor substrate 110 of the solar cell illustrated in FIGS. 3 and 4, (C142) may be spaced apart from each other and elongated in the first direction (x).

5 (c) and 5 (d), a plurality of first auxiliary electrodes P141 and a plurality of second auxiliary electrodes P142 are formed on the front surface of the insulating member 200 according to the present invention, And may be formed to be long in the first direction (x).

A first auxiliary electrode pad PP141 extending in a second direction y is further provided at the ends of the plurality of first auxiliary electrodes P141 formed in the first direction x on the front surface of the insulating member 200 And the first auxiliary electrode pad PP141 may be connected to the ends of the plurality of first auxiliary electrodes P141.

A second auxiliary electrode pad PP142 extending in the second direction y is further provided at the end of the plurality of second auxiliary electrodes P142 formed in the first direction x on the front surface of the insulating member 200 And the second auxiliary electrode pad PP142 may be connected to the ends of the plurality of second auxiliary electrodes P142.

The first auxiliary electrode P141 and the first auxiliary electrode pad PP141 may be integrally formed of the same material and the second auxiliary electrode P142 and the second auxiliary electrode pad PP142 may be integrally formed of the same material As shown in FIG.

Here, the first auxiliary electrode P141 and the second auxiliary electrode pad PP142 may be spaced apart from each other, and the second auxiliary electrode P142 and the first auxiliary electrode pad PP141 may be spaced apart from each other.

The first auxiliary electrode pad PP141 is formed in the second direction y at one end of both ends of the first direction x on the front surface of the insulating member 200 and the second auxiliary electrode pad PP142 may be formed in the second direction y, respectively.

As described above, in the solar cell according to the present invention, only one insulating member 200 is coupled to one semiconductor substrate 110 to form one integrated individual element, thereby making it easier to manufacture the solar cell module, Even if the semiconductor substrate 110 included in one of the solar cells is broken or defects are generated during the manufacturing process of the solar cell module, only the corresponding solar cell formed by one integrated type individual element can be replaced and the process yield can be further improved have.

In addition, the solar cell formed by the single integrated device can minimize the thermal stress applied to the semiconductor substrate 110 during the manufacturing process.

Here, when the area of the insulating member 200 is equal to or larger than the area of the semiconductor substrate 110, an interconnector (IC) may be attached to the front surface of the insulating member 200 when the solar cell and the solar cell are connected to each other It is possible to secure a sufficient area. To this end, the area of the insulating member 200 may be larger than the area of the semiconductor substrate 110, and may be less than twice.

The rear surface of the semiconductor substrate 110 and the front surface of the insulating member 200 are adhered to each other so that the first electrode C141 and the first auxiliary electrode P141 are connected to each other and the second electrode C142 and the second The auxiliary electrode P142 may be connected to each other.

5C, the widths of the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 are set such that the widths of the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142), that is, in the second direction (y). The width of the first auxiliary electrode pad PP141 may be changed between WP1a and WP1b and the width of the second auxiliary electrode pad PP142 may be changed between WP2a and WP2b Can be changed.

5C, in the portion having the maximum widths WP1a and WP2a, the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 extend to the ends of the insulating member 200 And the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 may expose a part of the insulating member 200 in a portion having the minimum widths WP1b and WP2b.

At this time, the planar shape of the ends of the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 may include a curved surface.

FIG. 6 is a view for explaining a state in which the semiconductor substrate 110 and the insulating member 200 shown in FIG. 5 are connected to each other. FIG. 7A is a cross-sectional view taken along line 7a-7a in FIG. Fig. 7B is a cross-sectional view taken along line 7B-7B in Fig. 6, and Fig. 7C is a cross-sectional view taken along line 7C-7C in Fig.

As shown in FIG. 6, one semiconductor substrate 110 may be completely overlapped with one insulating member 200 to form one solar cell individual element.

7A, the first electrode C141 formed on the rear surface of the semiconductor substrate 110 and the first auxiliary electrode P141 formed on the front surface of the insulating member 200 are overlapped with each other, And can be electrically connected to each other by a connection material (ECA).

The second electrode C142 formed on the rear surface of the semiconductor substrate 110 and the second auxiliary electrode P142 formed on the front surface of the insulating member 200 are also overlapped with each other and electrically connected to each other by the electrode connector ECA .

The space between the first electrode C141 and the second electrode C142 may be filled with an insulating layer IL and a gap between the first auxiliary electrode P141 and the second auxiliary electrode P142 The insulating layer IL may be filled.

7B, the insulating layer IL may be filled in the spaced space between the second auxiliary electrode P142 and the first auxiliary electrode pad PP141. As shown in FIG. 7C, The insulating layer IL may be filled in the spaced space between the first auxiliary electrode P141 and the second auxiliary electrode pad PP142.

6, each of the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 may include a first region PP141-S1 and a second auxiliary electrode pad PP142-S1 overlapping the semiconductor substrate 110, And second regions PP141-S2 and PP142-S2 that do not overlap with the semiconductor substrate 110. [

As described above, the second area PP141-S2 of the first auxiliary electrode pad PP141 and the second area PP142 of the second auxiliary electrode pad PP142, which are provided for securing a space that can be connected to the inter connector IC, -S2). ≪ / RTI > The first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 according to the present invention include the second areas PP141-S2 and PP142-S2, respectively, In addition, when connecting the interconnector (IC), thermal stress stress on the semiconductor substrate 110 can be minimized.

7B and 7C, the second area PP141-S2 of the first auxiliary electrode pad PP141 to which the interconnector IC is connected and the second area PP141-S2 of the second auxiliary electrode pad PP142, Irregularities can be formed in the region PP142-S2, as mentioned in part of FIG. 1B above. Thus, the bonding strength with the interconnector (IC) can be further strengthened.

Here, the second regions PP141-S2 and PP142-S2 of the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 are arranged in the first direction x along the second direction y, The width is not constant and can be changed repeatedly from WPS1a to WPS1b or from WPS2a to WPS2b.

The first electrode C141 and the second electrode C142 formed on the semiconductor substrate 110 are overlapped with the first auxiliary electrode P141 and the second auxiliary electrode P142 formed on the insulating member 200 in a direction parallel to the first auxiliary electrode P141 and the second auxiliary electrode P142, The first electrode C141 and the second electrode C142 formed on the semiconductor substrate 110 are electrically connected to the first auxiliary electrode P141 formed on the insulating member 200 and the second auxiliary electrode P141 formed on the insulating member 200, The widths of the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 along the second direction y may be changed even when they are overlapped and connected to each other in the direction crossing the auxiliary electrode P142.

In addition, even when the first auxiliary electrode P141 and the second auxiliary electrode P142 are not formed in plural but are formed as a single tubular electrode, the first auxiliary electrode pad PP141 along the second direction y The width of the second auxiliary electrode pad PP142 may be changed.

The first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 are formed by only one of the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142, May be formed in plural numbers.

FIG. 8 is a view for explaining a second embodiment of the solar cell module according to the present invention, and FIG. 9 is a view for explaining the insulating member 200 of the solar cell applied to the solar cell module shown in FIG. to be.

8 and FIG. 9, the description of the same contents as those described above with reference to FIGS. 1 to 7C will be omitted.

8, in the solar cell module according to the present invention, the width at which the interconnector IC is connected to the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 is the width (IC) and the first auxiliary electrode pad (PP141) or the second auxiliary electrode pad (PP142) are connected to each other while the connection width gradually increases or decreases in the longitudinal direction (y) The connection width may be fixed to WC1 or WC2 and the interconnection IC and the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 may not be connected in the remaining sections.

At this time, the widths of WC1 and WC2 may be the same or different from each other. At this time, the structure of the interconnector (IC) may be the same as that described in Fig.

The structure of the semiconductor substrate 110 may be the same as that described with reference to FIGS. 3 to 5A and 5B, but the first auxiliary electrode P141 formed on the insulating member 200 and the second auxiliary electrode P142 ) Are different from those described in Fig. 5 (c).

For example, the patterns of the first auxiliary electrode P141 and the second auxiliary electrode P142 formed in the insulating member 200 of the solar cell applied to the solar cell module shown in FIG. 8 may be as shown in FIG.

As shown in FIG. 9, the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 may be formed in plural numbers.

A plurality of first auxiliary electrodes P141 are connected to each of the plurality of first auxiliary electrode pads PP141 and a plurality of second auxiliary electrodes P142 are connected to each of the plurality of second auxiliary electrode pads PP142. .

The plurality of first auxiliary electrode pads PP141 and the plurality of second auxiliary electrode pads PP142 may be arranged in the second direction y and the plurality of first auxiliary electrode pads PP141 may be arranged in the second direction y, (y), and the plurality of second auxiliary electrode pads PP142 may be spaced apart from each other in the second direction (y).

The end of the insulating member 200 is connected to a portion AOP where a plurality of first auxiliary electrode pads PP141 and second auxiliary electrode pads PP142 are formed and a plurality of first auxiliary electrode pads PP141, The second auxiliary electrode pad PP142 may not be formed and may include an exposed portion ANP.

Here, the widths WP1 and WP2 of the plurality of first auxiliary electrode pads PP141 and the second auxiliary electrode pads PP142 along the second direction y may be constant as shown in FIG.

Alternatively, the widths of the plurality of first auxiliary electrode pads PP141 and the second auxiliary electrode pads PP142 along the second direction y may be varied.

10 is a view for explaining another example of the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 shown in FIG.

10, each of the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 included in the plurality of first auxiliary electrode pads PP141 and the second auxiliary electrode pad PP142, The width in the first direction (x) along the second direction (y) can be changed.

10 (a) and 10 (b), each of the first auxiliary electrode pads PP141 and PP142 included in the plurality of first auxiliary electrode pads PP141 and the second auxiliary electrode pads PP142, ) Or the second auxiliary electrode pad PP142 may include a curved surface.

10A, the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 are arranged such that the edge width WPb in the second direction (y) The edge width WBa may be formed to be larger than the width WBa of the central portion as shown in FIG. 10 (b).

10 (c), the width of each of the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP14 linearly increases from the edge to the central portion, The portion may be of a shape that keeps the width constant. Therefore, the width WPa of the central portion may be larger than the width WPa of the edge portion.

In addition, in the solar cell according to the present invention, the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP14 may have various widths in the first direction (x) along the second direction (y) It can have a changing form.

The widths of the first and second auxiliary electrode pads PP141 and PP142 in the first direction x along the second direction y are changed as described above, The width at which the interconnector IC is connected to the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 may be changed in the second direction y that is the longitudinal direction y of the first auxiliary electrode pad PP.

Accordingly, when connecting the interconnector (IC) to each solar cell, a phenomenon in which the insulating member 200 is bent due to a difference in thermal expansion coefficient can be minimized, It is possible to minimize the phenomenon that the semiconductor substrate 110 is damaged or damaged in the tabbing process of connecting the interconnector (IC).

11 to 14 are views for explaining a third embodiment of the solar cell module according to the present invention.

11 is an example in which an interconnector (IC) having different widths in the longitudinal direction is applied to the solar cell module, FIG. 12 is an example of a solar cell applied to the solar cell module of FIG. 11, 13 is a view for explaining a semiconductor substrate 110 and an insulating member 200 in another solar cell that can be applied to the battery module, and FIG. 14 is a cross-sectional view of the semiconductor substrate 110 and the insulating member 200 shown in FIG. Are connected integrally with each other.

11, the solar cell module according to the present invention has a connection width (width) at which a first auxiliary electrode pad PP141 or an interconnector IC and a second auxiliary electrode pad PP142 are connected to each other, (IC) having a constant width along the longitudinal direction (y) of the interconnector (IC) can be used in order to change the length of the interconnector (IC) in the longitudinal direction (y) .

That is, at the first position in the second direction y, the width of the interconnector IC may be WIa, and at the second position, the width of the interconnector IC may be WIb less than WIa. Therefore, in the first position, the interval between the inter connector IC and the semiconductor substrate 110 can be as small as GSI1a or GSI2a, and in the second position, the interval between the inter connector IC and the semiconductor substrate 110 becomes GSI1a It can be larger than GSI2a with GSI1b or GSI2b.

The plane of the solar cell having the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 may be as shown in FIG.

12, a solar cell according to a third embodiment of the present invention includes a first electrode C141 and a second electrode C142 formed on a rear surface thereof, An insulating member 200 having a substrate 110 and a first auxiliary electrode P141 and a first auxiliary electrode pad PP141 and a second auxiliary electrode P142 and a second auxiliary electrode pad PP142 formed on the front surface thereof Solar cells integrally connected can be used.

The structure of the solar cell shown in Fig. 12 is the same as that described with reference to Figs. 3 to 7C except for the widths of the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142, and thus a detailed description thereof will be omitted.

12, the solar cell applied to the third embodiment of the solar cell module may include a first auxiliary electrode pad PP141 or a second auxiliary electrode pad PP142 along the second direction y, ) May be constant.

12, the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 may be formed up to the end of the insulating member 200, The widths WPS1 and WPS2 in the first direction x from the end to the ends of the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 may be constant.

In addition, the solar cell shown in FIG. 13 and FIG. 14 may be used for the solar cell module shown in FIG.

Specifically, when the semiconductor substrate 110 is formed of only a single crystal silicon substrate, the corner portion of the semiconductor substrate 110 may be formed in an oblique direction as shown in FIG. 13 (a). However, even in such a case, the patterns of the first electrode C141 and the second electrode C142 may be the same as those described in FIG. 5A.

However, in this case, the pattern of the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 may be different in the insulating member 200. That is, a part of the pattern of the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 is formed in the second direction y as described with reference to FIG. 5A, The portion of the pattern of the second auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 overlapping with the edge of the semiconductor substrate 110 formed in a diagonal line may be formed in an oblique direction in the same direction as the edge portion of the semiconductor substrate 110 have.

The widths WP1a and WP2a of the pattern of the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 formed by the oblique lines are the widths WP1b and WP2b formed in the second direction y, Can be formed larger.

As described above, in the pattern of the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142, the portion formed by the slanting line may not be connected to the inter connector IC, and the first auxiliary electrode pad PP141, 2 auxiliary electrode pad PP142 in the second direction y is relatively smaller than the length of the portion formed in the second direction y in the auxiliary electrode pad PP142 and is formed in a diagonal direction even when the inter connector IC is connected, The degree of the relative bending of the insulating member 200 may be weak.

Therefore, the widths WP1a and WP2a of the portions formed by the oblique lines in the patterns of the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 are set to the widths WP1b and WP2b of the portions formed in the second direction y, The sheet resistance at both ends of the patterns of the first auxiliary electrode pad PP141 and the second auxiliary electrode pad PP142 can be further lowered.

The case where the semiconductor substrate 110 and the insulating member 200 shown in FIG. 13 are integrally connected as shown above may be as shown in FIG.

In this way, when the semiconductor substrate 110 and the insulating member 200 are integrally connected, a part of the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 does not overlap the semiconductor substrate 110 , Can be exposed out.

The connection width of the interconnection IC and the first auxiliary electrode pad PP141 or the second auxiliary electrode pad PP142 in the solar cell module according to the present invention is smaller than the connection width in the longitudinal direction y of the interconnection IC, (1) and (2) in FIG. 1, only the case of (1) and (2) can be used in combination as explained in FIG. It is possible. A detailed description thereof will be omitted.

In addition, the interconnector (IC) for connecting the plurality of solar cell modules to each other may be formed in a structure for further improving the adhesive force, which will be described below.

15 is a view for explaining the overall cross-sectional structure of the solar cell module according to the first to third embodiments.

15, in addition to the cell string in which the first solar cell (Cell-a) and the second solar cell (Cell-b) are connected to each other as described above, A substrate, an upper encapsulant, a lower encapsulant, and a back sheet.

Here, in each of the plurality of solar cells including the first solar cell Cell-a and the second solar cell Cell-b, the semiconductor substrate 110 and the insulating member 200 are separately connected to one another, Can be formed.

15, the front glass substrate FG is formed on the front surface of a cell string in which the first solar cell Cell-a and the second solar cell Cell-b are connected to each other by an interconnection IC And it can be made of tempered glass or the like to have a high transmittance and to prevent breakage. At this time, the tempered glass may be a low iron tempered glass having a low iron content, and although not shown, the inner side may be subjected to an embossing treatment to enhance the light scattering effect.

The top sealing material EC1 may be positioned between the front glass substrate FG and the cell string and the bottom sealing material EC2 may be positioned between the back side of the cell string ie the back sheet BS and the cell string .

The upper encapsulating material EC1 and the lower encapsulating material EC2 may be formed of a material that protects the solar cell module 100 from an impact and prevents corrosion of metal due to moisture penetration. For example, ethylene vinyl acetate (EVA), or the like.

As shown in FIG. 16, the upper encapsulating material EC1 and the lower encapsulating material EC2 are disposed on the front and rear surfaces of the plurality of solar cells, respectively. In the lamination process, Can be integrated.

In addition, the rear sheet BS is placed on the rear surface of the bottom sealing material EC2 in the form of a sheet to prevent moisture from penetrating into the rear surface of the solar cell module. Such a backsheet (BS) may be made of an insulating material such as EP / PE / FP (fluoropolymer / polyeaster / fluoropolymer).

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 (19)

A plurality of first electrodes formed on a rear surface of the semiconductor substrate, a plurality of second electrodes formed on the rear surface of the semiconductor substrate, a first auxiliary electrode and a first auxiliary electrode pad connected to the plurality of first electrodes, A first solar cell and a second solar cell including an insulating member having a second auxiliary electrode and a second auxiliary electrode pad connected to the second electrode of the second solar cell; And
The first auxiliary electrode pad of the first solar cell and the second auxiliary electrode pad of the second solar cell or the first auxiliary electrode pad of the first solar cell and the second auxiliary electrode pad of the second solar cell, And an interconnect connector electrically connected to the auxiliary electrode pad,
Wherein at least one of the connecting surfaces of the interconnector and the first and second auxiliary electrode pads has irregularities. 3. The method of claim 2,
Wherein at least one of a portion of the interconnector connected to the first and second auxiliary electrode pads and a portion of each of the first and second auxiliary electrode pads connected to the interconnector are provided with projections and depressions. 3. The method of claim 2,
Wherein a width of connection between the interconnector and the first auxiliary electrode pad or between the interconnector and the second auxiliary electrode pad changes as the longitudinal direction of the interconnector progresses. The method of claim 3,
The connection width has a maximum connection width and a minimum connection width,
Wherein the maximum connection width and the minimum connection width are repeated as the length of the interconnector increases. 5. The method of claim 4,
Wherein the interconnector is spaced apart from the first auxiliary electrode pad or the second auxiliary electrode pad at a portion having the minimum connection width. The method of claim 3,
Wherein the planar shape in which the interconnector is connected to the first auxiliary electrode pad or the second auxiliary electrode pad includes a curved surface. The method of claim 3,
The solar cell module
A front glass substrate positioned above a front surface of a cell string in which the first solar cell and the second solar cell are connected to each other by the interconnector;
An upper encapsulant positioned between the front glass substrate and the cell string;
A lower encapsulant positioned on a rear surface of the cell string; And
And a rear sheet positioned on a rear surface of the lower sealing member. The method of claim 3,
Wherein each of the first auxiliary electrode and the second auxiliary electrode extends in the first direction,
Wherein the first auxiliary electrode pad is connected to an end of the first auxiliary electrode extending in the first direction and extends in a second direction intersecting the first direction,
And the second auxiliary electrode pad is connected to an end of the second auxiliary electrode extending in the first direction, and extends in the second direction. 9. The method of claim 8,
Each of the first auxiliary electrode pad and the second auxiliary electrode pad
And the width in the first direction is not constant in the second direction. 9. The method of claim 8,
Wherein the ends of the first auxiliary electrode pad and the second auxiliary electrode pad each include a curved surface. 9. The method of claim 8,
The first auxiliary electrode pad and the second auxiliary electrode pad are each a plurality of,
Wherein the plurality of first auxiliary electrode pads are spaced apart from each other,
Wherein the plurality of second auxiliary electrode pads are spaced apart from each other. The method of claim 3,
And the width of the interconnector is constant as the interconnector proceeds in the second direction. The method of claim 3,
And the width of the interconnector is not constant as it progresses in the second direction. A semiconductor substrate;
A plurality of first electrodes formed on a rear surface of the semiconductor substrate;
A plurality of second electrodes formed on the rear surface of the semiconductor substrate so as to be spaced apart from and spaced apart from the plurality of first electrodes;
A first auxiliary electrode connected to the plurality of first electrodes, a first auxiliary electrode pad connected to an end of the first auxiliary electrode, a second auxiliary electrode connected to the plurality of second electrodes, And an insulating member including a second auxiliary electrode pad connected to an end,
Wherein the first auxiliary electrode pad and the second auxiliary electrode pad are connected to an interconnector interconnecting the plurality of solar cells,
Wherein at least a portion of the first auxiliary electrode pad and the second auxiliary electrode pad that is connected to the interconnector is provided with concave and convex portions. 15. The method of claim 14,
Wherein widths of the first auxiliary electrode pad and the second auxiliary electrode pad are changed as the width of the first auxiliary electrode pad and the second auxiliary electrode pad progresses in the longitudinal direction of the first auxiliary electrode pad and the second auxiliary electrode pad. 16. The method of claim 15,
Wherein each of the first auxiliary electrode and the second auxiliary electrode extends in the first direction,
Wherein the first auxiliary electrode pad is connected to an end of the first auxiliary electrode extending in the first direction and extends in a second direction intersecting the first direction,
Wherein the second auxiliary electrode pad is connected to an end of the second auxiliary electrode extending in the first direction and extends in the second direction. 17. The method of claim 16,
Each of the first auxiliary electrode pad and the second auxiliary electrode pad
And the width in the first direction is not constant in the second direction. 17. The method of claim 16,
Wherein planar shapes of ends of each of the first auxiliary electrode pad and the second auxiliary electrode pad include curved surfaces. 17. The method of claim 16,
The first auxiliary electrode pad and the second auxiliary electrode pad are each a plurality of,
Wherein the plurality of first auxiliary electrode pads are spaced apart from each other,
Wherein the plurality of second auxiliary electrode pads are spaced apart from each other.

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