DE102012216740B4 - A silicon solar cell produced by dicing an output solar cell formed on a silicon wafer, a photovoltaic module, and a solar cell manufacturing method - Google Patents

Abstract

Silicon solar cell (560, 570),
which is produced by dividing an output solar cell (500) formed on a silicon wafer (300),
wherein the silicon wafer (300) has a surface (350) that is at least 80% formed by a {100} plane,
wherein the wafer (300) has a first outer edge (310),
wherein a nip plane (260) of the wafer (300) intersects the surface (350) parallel to two opposite outer edges (320, 340) of the wafer (300) in a cut line (390),
the output solar cell (500)) being divided along this section line (390),
wherein a breaking edge along the cutting line (390) has no predetermined breaking mark in the predominant region,
wherein the breaking edge at one or both corner regions has a predetermined breaking mark (370, 380).

Description

The present invention relates to a silicon solar cell produced by dicing an output solar cell formed on a silicon wafer, a photovoltaic module having silicon solar cells, and a method of manufacturing a solar cell.

Solar cells are electronic components that convert electromagnetic radiation energy into electrical energy. The electromagnetic radiation energy may in particular be sunlight. It is known to produce solar cells from monocrystalline silicon. Such monocrystalline cells are characterized by high efficiency.

It is, for example, from the DE 12 82 204 A known to produce monocrystalline silicon cells from monocrystalline silicon wafers, which are produced by the Czochralski method or by the zone melting process. However, these methods are associated with high production costs. From the DE 10 2010 029 741 A1 In addition, a method is known for producing silicon wafers more cost-effectively from monocrystalline silicon blocks.

It is known that high currents associated with high efficiencies of monocrystalline silicon solar cells lead to high resistance losses. To reduce the resistance losses, it is known to reduce a parallel connected cell surface in photovoltaic modules with silicon solar cells in favor of a series connection. For this purpose, output solar cells are split to obtain two or more silicon solar cells, which are then connected in series.

The DE 20 2012 004 369 U1 describes a photovoltaic module having a front glass cover, a back cover and a number of interconnected solar cells disposed between the front and back covers in an embedding layer, the solar cells having a rectangular shape with an aspect ratio of 2: 1.

The US 2003/0 129 809 A1 describes the application of notches on a surface of a wafer with semiconductor devices. Subsequently, the surface is covered with a protective film before the wafer, starting from the notches, is divided along crystal planes.

The DE 10 2010 020 974 A1 describes a method for producing special solar cells from a wafer. It is exploited that a simple cleavage of crystals along crystal orientations is possible.

The dividing of the output solar cell is performed by breaking a silicon wafer of the output solar cell. However, this can lead to an uncontrolled breakage of the wafer.

An object of the present invention is to provide a silicon solar cell produced by dicing an output solar cell formed on a silicon wafer. This object is achieved by a silicon solar cell with the features of claim 1. Another object of the present invention is to provide a photovoltaic module. This object is achieved by a photovoltaic module having the features of claim 4. Another object of the present invention is to provide a method for producing a solar cell. This object is achieved by a method having the features of claim 5. Preferred developments are specified in the dependent claims.

A silicon solar cell is produced by dicing an output solar cell formed on a silicon wafer. In this case, the silicon wafer has a surface which is at least 80% formed by a {100} plane. In this case, the wafer has a first outer edge. In this case, a cleavage plane of the wafer intersects the surface parallel to two opposite outer edges of the wafer in a cutting line. The output solar cell is divided along this section line. Advantageously, this silicon solar cell is produced from an output solar cell whose silicon wafer has a cleavage plane which is oriented at right angles to an outer edge of the output solar cell. As a result, the division of the output solar cell into the silicon solar cell can be carried out in a simple, cost-effective and controlled manner, whereby a high yield with low production costs can be achieved.

In one embodiment of the silicon solar cell, the cleavage plane is a {111} plane. Here, the first outer edge is oriented perpendicular to a <110> direction. Advantageously, a silicon crystal along a {111} plane can be broken particularly easily and reliably.

In one embodiment of the silicon solar cell, the cleavage plane runs to the surface of the wafer at an angle between 50 ° and 60 °, in particular at an angle of arctan √2.

In the silicon solar cell, a breaking edge is formed along the cutting line. In this case, the breaking edge has no predetermined breaking mark in the predominant area.

In the case of the silicon solar cell, the fracture edge has a predetermined breaking mark at one or both corner regions.

A photovoltaic module comprises a plurality of silicon solar cells of the aforementioned type.

In one embodiment of the photovoltaic module, the latter comprises two silicon solar cells which are produced by dividing an output solar cell formed on a silicon wafer. The silicon wafer has a surface which is formed by at least 80% through a {100} plane. The wafer also has a first outer edge. A cleavage plane of the wafer is oriented perpendicular to the first outer edge. The cleavage plane encloses an angle between 50 ° and 60 ° with the surface of the wafer. Advantageously, the silicon solar cells of this photovoltaic module are produced from an output solar cell whose silicon wafer has a cleavage plane which is oriented at right angles to an outer edge of the output solar cell. As a result, the division of the output solar cell into the silicon solar cell can be carried out in a simple, cost-effective and controlled manner, whereby a high yield with low production costs can be achieved.

In one embodiment of the photovoltaic module, the output solar cell is divided along the cleavage plane. Advantageously, the output solar cell is thereby divided along a preferential fracture direction, thereby preventing erroneous breakage of the output solar cell.

In one embodiment of the photovoltaic module, the cleavage plane is a {111} plane. Advantageously, a silicon crystal along a {111} plane can be broken particularly easily and reliably.

In one embodiment of the photovoltaic module, the first outer edge is oriented perpendicular to a <110> direction. Advantageously, the wafer may then be broken perpendicular to the first outer edge, whereby the silicon solar cells may have a rectangular shape.

In one embodiment of the photovoltaic module, the wafer has a second outer edge, which is oriented perpendicular to the first outer edge. Advantageously, the wafer can then be divided perpendicular to the second outer edge, whereby the silicon solar cells can have a rectangular shape.

A method of manufacturing a solar cell includes steps of providing a cuboid crystal having an end face formed of at least 80% by a {100} plane, the crystal having a side surface with a cleavage plane of the crystal oriented perpendicular to the side surface , wherein the cleavage plane with the end face encloses an angle between 50 ° and 60 °, for dicing the crystal to obtain a wafer having a surface formed of at least 80% by a {100} plane, the wafer having a first outer edge formed from the side surface, and for dicing the wafer, the dicing being carried out starting from a notch located at the first outer edge. Advantageously, the wafer is cut reliably in this method perpendicular to the first outer edge of the wafer, without it being necessary to provide the wafer with a predetermined breaking point along the entire intended breaking line before the cutting. As a result, the method is simple and inexpensive to perform. In particular, this avoids problems that may be associated with the creation of a predetermined breaking point. If such a predetermined breaking point is applied by means of a laser as a laser ditch, it can lead to the deposition and solidification of silicon melt in this laser ditch. Then there is a risk that the wafer breaks uncontrollably during cutting. If the predetermined breaking point is produced using a scoring tool in a mechanical scribing method, the required scoring over the entire predetermined breaking point leads to high wear of the scoring tool. These problems are avoided in the method mentioned in that the division of the wafer takes place starting from a notch arranged only at the first outer edge of the wafer.

In this case, the division takes place along the cleavage plane. Advantageously, the dicing then takes place particularly reliably along the desired breaking direction.

In one embodiment of the method, the cleavage plane is a {111} plane. Advantageously, a {111} plane of a silicon crystal represents a preferential fracture plane of the silicon crystal.

In one embodiment of the method, the notch is applied prior to dicing the crystal. Advantageously, the wafers obtained by dividing the crystal from the crystal then already directly have the required notch.

In another embodiment of the method, the notch is applied after dicing the crystal. Advantageously, this prevents accidental breakage of the wafers formed during the dicing of the crystal during the dicing of the crystal.

In one embodiment of this method, a plurality of wafers are stacked on top of each other, with all the wafers of the stack simultaneously a notch be provided. Advantageously, a multiplicity of wafers can then also be provided with a notch at the same time according to this method, as a result of which the method can be carried out quickly and inexpensively.

In one embodiment of the method, the notch is applied by mechanical scribing. Advantageously, this is a reliable way to create the notch.

In another embodiment of the method, the notch is applied by means of a laser. Advantageously, this also represents a reliable way to create the notch.

In one embodiment of the method, the wafer is divided between the notch and a second notch located at a third outer edge of the wafer. Advantageously, the dicing of the wafer then takes place particularly reliably in the desired breaking direction between the two notches of the wafer.

In one embodiment of the method, prior to dicing the wafer, a further step is performed to fabricate an output solar cell on the wafer. Advantageously, when dividing the wafer, two silicon solar cells then emerge from the output solar cell. Advantageously, these can be connected in series in a photovoltaic module.

The invention will be explained in more detail with reference to the accompanying figures. Showing:

1 a schematic perspective view of a silicon block;

2 a schematic perspective view of a silicon column;

3 a further schematic representation of the silicon column;

4 a schematic representation of a wafer stack;

5 a schematic plan view of a silicon wafer;

6 a schematic perspective view of a Ausgangsolarzelle;

7 a schematic representation of a photovoltaic module;

8th a flowchart of a first method; and

9 a flowchart of another method.

In the following description, Miller indices are used to denote crystal directions and planes. The indices are given as number triplets referring to basis vectors of a lattice coordinate system of the crystal. Number triplets (hkl) denote a specific crystal plane. Number triplets {hkl} denote all symmetrically equivalent lattice planes of the crystal. Number triplets [hkl] denote a crystal direction. Number triple <hkl> denotes all crystal directions that are symmetrically equivalent to the direction [hkl]. In the cubic crystal lattice of a diamond crystal silicon crystal, the direction [hkl] is perpendicular to the plane (hkl).

1 shows a schematic perspective view of a substantially monocrystalline (monocrystalline) silicon block 100 , The silicon block 100 has a cuboid basic shape. The silicon block 100 may have an edge length of 70 cm or more. A height of the silicon block 100 can be 30 cm or more.

The silicon block 100 has been prepared by melting and crystallizing ultrapure silicon in a crucible by a per se known method. For this purpose, a silicon monocrystal seed was arranged in a bottom region of the crucible. The silicon block 100 was formed by crystallization of molten ultrapure silicon on the silicon single crystal seed. At this time, the crystal orientation predetermined by the silicon single crystal nucleus became the silicon block 100 transfer.

An end face of the silicon block 100 points in a first crystal direction 110 , A side surface of the silicon block 100 points in a second crystal direction 120 , A surface of the silicon block parallel to the silicon single crystal seed 100 points in a third crystal direction 130 , The first crystal direction 110 is a <100> direction. The second crystal direction 120 is a <110> direction in the example shown, but could also be a <100> direction. The third crystal direction 130 is also a <110> direction in the example shown, but could also be a <100> direction.

The silicon block 100 is by sawing into a plurality of silicon pillars 200 been divided. Every silicon pillar 200 has a first side surface 210 , a second side surface 220 , a third side surface 230 and a fourth side surface 240 on. In addition, each silicon column has 200 an end face 250 on. The silicon block 100 became so in silicon pillars 200 sawed that the end faces 250 the silicon pillars 200 in the first crystal direction 110 , so in a <100> direction. The third side surfaces 230 all silicon pillars 200 have in a <110> direction, in the example shown in the second crystal direction 120 , The second side surfaces 220 all silicon pillars 200 also point in a <110> direction, in the illustrated example in the third crystal direction 130 ,

The cuts to form the silicon pillars 200 are parallel to the outer edges of the silicon block in the illustrated example 100 he follows. Would be the second crystal direction 120 and the third crystal direction 130 of the silicon block 100 however, <100> directions, the saw cuts would be at an angle of 45 ° with respect to the outside edges of the silicon ingot 100 he follows. Also in this case would be the second side surfaces 220 and the third side surfaces 230 the silicon pillars 200 now point in <110> directions.

From every silicon pillar 200 may be a plurality of silicon wafers 300 be won. For this purpose, the silicon columns 200 through parallel to the faces 250 running cuts in silicon wafers 300 divided. The resulting silicon wafers 300 are formed as rectangular, in particular square, discs with very small thickness.

Every silicon wafer 300 has a first outer edge 310 , a second outer edge 320 , a third outer edge 330 , a fourth outer edge 340 and a surface 350 on. The outer edges 310 . 320 . 330 . 340 make very thin surface sections of the respective side surfaces 210 . 220 . 230 . 240 However, because of their narrowness in this description, they are referred to as edges. The first outer edge 310 is from the first side surface 210 the respective silicon column 200 emerged. The second outer edge 320 is accordingly from the second side surface 220 the silicon column 200 emerged. The third outer edge 330 of the silicon wafer 300 and the fourth outer edge 340 are accordingly from the third side surface 230 and the fourth side surface 240 the silicon column 200 emerged.

The surface 350 every silicon wafer 300 is parallel to the face 250 the original silicon pillar 200 oriented. Thus, the surface faces 350 every silicon wafer 300 in the first crystal direction 110 So a <100> direction. The outer edges 310 . 320 . 330 . 340 every silicon wafer 300 are each perpendicular to <110> directions.

2 shows in an enlarged view a perspective schematic view of one of the silicon columns 200 , A silicon wafer 300 by dividing the silicon column 200 is available, is also indicated schematically.

2 further shows a cleavage plane 260 the silicon column 200 , The cleavage plane 260 is a {111} plane of the silicon column 200 , The cleavage plane 260 closes with the face 250 the silicon column 200 an angle 140 one. Depending on the accuracy with which the end face 250 the silicon column 200 in the <100> direction 110 indicates, the angle is between 50 ° and 60 °. Indicates the face 250 the silicon column 200 exactly in the <100> direction 110 , so is the angle 140 about 54.74 °. As close as possible to this value is preferred.

A cut line between the cleavage plane 260 and the silicon wafer 300 makes a break line 390 , The break line 390 is within the accuracy with which the silicon pillar 200 from the silicon block 100 was cut, parallel to the second outer edge 320 and to the fourth outer edge 340 of the silicon wafer 300 and perpendicular to the first outer edge 310 and to the third outer edge 330 of the silicon wafer 300 oriented.

The cleavage plane 260 the silicon column 200 is a crystal plane from which the crystal of the silicon column 200 preferably splits. A mechanical crack of the crystal of the silicon column 200 grows preferentially along the cleavage plane 260 , Tried, the silicon column 200 along a to the cleavage plane 260 non-parallel plane or the silicon wafer 300 along a to the break line 390 Non-parallel line to divide, so it happens easily that the respective break nevertheless along the cleavage plane 260 or the break line 390 continues.

The silicon wafer 300 may serve as a starting material for producing a Ausgangsolarzelle, as will be explained in more detail below. Subsequently, the output solar cell along the break line 390 of the silicon wafer 300 be divided to obtain two silicon solar cells. These silicon solar cells can be connected in series in a photovoltaic module, as will be explained in more detail below.

The silicon wafer 300 should along the break line 390 be parted. Because the break line 390 a preferred breaking line of the silicon wafer 300 is, it is enough, the silicon wafer 300 in the area of its first outer edge 310 in which the break line 390 the first outer edge 310 cuts, with a notch to provide. Will the silicon wafer 300 then mechanically loaded, it comes from the notch to a crack growth along the break line 390 so that the silicon wafer 300 along the fault line 390 breaks. At the fault line 390 then forms a broken edge. An even more reliable breaking of the silicon wafer 300 along the fault line 390 can be achieved by the fact that the third outer edge 330 of the silicon wafer 300 at the point where the desired break line 390 the third outer edge 330 cuts, has a notch. The breakage of the silicon wafer 300 then takes place along the break line 390 between the two notches in the first outer edge 310 and the third outer edge 330 ,

3 shows a further perspective view of the silicon column 200 and the silicon wafer 300 by dividing the silicon column 200 is available. The silicon wafer 300 is however in the representation of the 3 not yet from the silicon column 200 separated.

The first side surface 210 the silicon column 200 is with a first groove 270 been provided, extending between the second side surface 220 and the fourth side surface 240 and parallel to the second side surface 220 and the fourth side surface 240 the silicon column 200 over the entire length of the first side surface 210 extends. The first groove 260 For example, by scratching the silicon column 200 be produced with a carbide tip or a diamond tip. The first groove 270 may also have been generated by means of a laser.

In the example shown, the first groove 270 centered between the second side surface 220 and the fourth side surface 240 arranged to the silicon wafer 300 to divide into two equal sections. Should the silicon wafer 300 divided into different large sections, so would the groove 270 according to arrange differently. Should the silicon wafer 300 be divided into more than two sections, so would correspond more than one groove 270 provided.

The third side surface 230 the silicon column 200 has a second groove 280 on, the middle between the second side surface 220 and the fourth side surface 240 arranged and parallel to the first groove 270 is oriented. The second groove 280 can be like the first groove 270 be generated by scratching or by means of a laser. On the second groove 280 can also be dispensed with in a simplified embodiment.

Will the silicon wafer 300 by dividing the silicon column 200 from the silicon column 200 separated, so has the silicon wafer 300 one through the first groove 270 the silicon column 200 formed first notch (break mark) 370 at its first outer edge 310 and one through the second groove 280 formed second notch (break mark) 380 at its third outer edge 330 on. All others from the silicon column 200 produced silicon wafers have corresponding notches. By creating the grooves 270 . 280 So all the silicon wafers were out of the silicon pillar 200 be generated, already with notches 370 . 380 Mistake.

Will the out of the silicon column 200 available silicon wafers 300 in a subsequent process step on the break line 390 between the first notch 370 and the second notch 380 divided, so arises from the silicon wafer 390 a first sub-wafer 391 and a second sub-wafer 392 ,

4 shows a schematic representation of a wafer stack 400 , The wafer stack 400 includes a plurality of silicon wafers 300 by dividing the silicon column 200 have arisen. The wafer stack can be, for example, 100 silicon wafers 300 include. This was the silicon column 200 in the silicon wafer 300 Parted without the silicon column 200 before with the first groove 270 and the second groove 280 was provided.

Instead, the individual silicon wafers were 300 after dividing the silicon column 200 in the wafer stack 400 arranged to the silicon wafer 300 of the wafer stack 400 together with first notches 370 and optionally also second notches 380 to provide. For this purpose, the wafer stack 400 with a first groove 470 provided by the first notches 370 in the silicon wafers 300 of the wafer stack 400 be formed. Optionally, the wafer stack 400 also provided with a second groove to second notches 380 in the silicon wafers 300 to create.

After the silicon wafer 300 of the wafer stack 400 with first nicks 370 and optionally also second notches 380 can be provided, the silicon wafer 300 again at the fault line 390 be divided to first sub-wafers 391 and second sub-wafers 392 to obtain.

5 shows a highly schematic representation of a plan view of the surface 350 one of the silicon wafers 300 in a processing state during production of an output solar cell from the silicon wafer 300 , The surface 350 of the silicon wafer 300 is with a texture 355 has been provided, which allows improved light coupling by reduced reflection losses. This causes the texture 355 an increase in the efficiency of the silicon wafer 300 produced output solar cell or the silicon solar cells produced from the Ausgangsolarzelle. The creation of the texture 355 (Texturing) was effected by wet or dry chemical etching. The texture 355 is formed as a pyramidal structure with a plurality of pyramidal elevations. The edges of each pyramid-shaped elevation preferably run parallel to the outer edges 310 . 320 . 330 . 340 of the silicon wafer 300 ,

6 shows a schematic perspective view of one of the silicon wafer 300 generated output solar cell 500 after further processing. The representation of the output solar cell 500 is to be understood as an example only. After making the texture 355 a high-temperature step was carried out in which a pn junction 510 by doping in the silicon wafer 300 was created. Preferably, the pn junction became 510 produced by phosphorus diffusion. Subsequently, the surface became 350 of the silicon wafer 300 tempered, preferably by applying an antireflection coating. Then an electrically conductive front side contact 520 on the surface 350 of the silicon wafer 300 and an electrically conductive backside contact 530 on one of the surface 350 opposite bottom of the silicon wafer 300 applied. The front side contact was preferred 520 and the backside contact 530 by a screen printing method on the silicon wafer 300 arranged.

The output solar cell 500 can in a subsequent process step by dividing the silicon wafer 300 the output solar cell 500 in a first silicon solar cell 560 and a second silicon solar cell 570 be parted. The first silicon solar cell 560 is then through the first sub-wafer 391 of the silicon wafer 300 educated. The second silicon solar cell 570 is through the second sub-wafer 392 of the silicon wafer 300 the output solar cell 500 educated.

7 shows a highly schematic sectional view of a photovoltaic module 500 , which is the first silicon solar cell 560 and the second silicon solar cell 570 having. The first silicon solar cell 560 and the second silicon solar cell 570 are in a series connection 580 arranged. The series connection connects 580 as an example, the backside contact 530 the first silicon solar cell 560 with the front side contact 520 the second silicon solar cell 570 , The photovoltaic module 550 may include a variety of other silicon solar cells.

8th shows a schematic flow diagram of a first method 600 for the preparation of the Ausgangsolarzelle 500 , It is in a first step 610 the cuboid silicon column 200 provided. The silicon column 200 is provided so that its face 250 is at least 80% formed by a {100} plane. In addition, the cleavage plane 260 the silicon column 200 perpendicular to the first side surface 210 the silicon column 200 oriented and closes with the face 250 an angle between 50 ° and 60 °.

In a second process step 620 becomes the silicon pillar 200 with the first groove 270 Mistake. Optionally, the silicon column 200 also with the second groove 280 Mistake. The grooves 270 . 280 can be created by scratches with a carbide tip or a diamond tip or by means of a laser.

In a third process step 630 becomes the silicon pillar 200 in single silicon wafers 300 divided. The surfaces 350 the single silicon wafer 300 In turn, at least 80% are formed by a {100} plane.

In a fourth process step 640 gets out of one of the silicon wafers 300 the output solar cell 500 produced.

In a fifth process step 650 becomes the output solar cell 500 by dividing the silicon wafer 300 along the fault line 390 in the first silicon solar cell 560 and the second silicon solar cell 570 divided. The break line 390 lies in the cleavage plane 260 the silicon column 200 ,

9 shows a schematic flow diagram of a second method 700 for the preparation of the Ausgangsolarzelle 500 ,

In a first process step 710 in turn becomes the silicon pillar 200 provided. The process step 710 of the procedure 700 corresponds to the process step 610 of the procedure 600 ,

In a second process step 720 becomes the silicon pillar 200 parted to the silicon wafer 300 to obtain. In the process 700 becomes the silicon pillar 200 so, without breaking it first with the first groove 270 and the second groove 280 to provide.

In a third process step 730 gets out of one of the silicon wafers 300 the output solar cell 500 produced. The third process step 730 of the procedure 700 corresponds to the fourth method step 640 of the procedure 600 ,

In a fourth process step 740 become the silicon wafers 300 several output solar cells 500 in the wafer stack 400 arranged. In a fifth process step 750 are all silicon wafers 300 of the wafer stack 400 with the first notch 370 and optionally with the second notch 380 Mistake.

In a sixth process step 760 becomes the silicon wafer 300 the output solar cell 500 along the fault line 390 parted to the first silicon solar cell 560 and the second silicon solar cell 570 to obtain.

After carrying out the procedure 600 or 700 can be the first silicon solar cell 560 and the second silicon solar cell 570 in series connection 580 be arranged to the photovoltaic module 550 to build.

LIST OF REFERENCE NUMBERS

100

Silicon block

110

<100> direction

120

<110> direction

130

<110> direction

140

angle

200

Silicon column

210

first side surface

220

second side surface

230

third side surface

240

fourth side surface

250

face

260

cleavage plane

270

first groove

280

second groove

300

Silicon wafer

310

first outer edge

320

second outer edge

330

third outer edge

340

fourth outer edge

350

surface

355

texture

370

first notch

380

second notch

390

breakline

391

first sub-wafer

392

second sub-wafer

400

Wafer stack

470

first groove

500

Output solar cell

510

pn junction

520

Front contact

530

Back contact

550

photovoltaic module

560

first silicon solar cell

570

second silicon solar cell

580

series connection

600

method

610

Provide a crystal

620

Create a notch

630

Dicing the crystal to obtain a wafer

640

Making a source solar cell on the wafer

650

Dicing the output solar cell to obtain solar cells

700

method

710

Provide a crystal

720

Dicing the crystal to obtain a wafer

730

Making a source solar cell on the wafer

740

Stacking a plurality of wafers

750

Create a notch

760

Dicing the output solar cell to obtain solar cells

Claims (12)

Silicon solar cell ( 560 . 570 ) by dividing one on a silicon wafer ( 300 ) formed output solar cell ( 500 ), wherein the silicon wafer ( 300 ) a surface ( 350 ), which is formed by at least 80% through a {100} plane, wherein the wafer ( 300 ) a first outer edge ( 310 ), wherein a cleavage plane ( 260 ) of the wafer ( 300 ) the surface ( 350 ) parallel to two opposite outer edges ( 320 . 340 ) of the wafer ( 300 ) in a section line ( 390 ), the output solar cell ( 500 )) along this section line ( 390 ), wherein a breaking edge along the cutting line ( 390 ) has no predetermined breaking mark in the predominant region, wherein the breaking edge at one or both corner regions has a predetermined breaking mark ( 370 . 380 ) having. Silicon solar cell ( 560 . 570 ) according to claim 1, wherein the cleavage plane ( 260 ) is a {111} plane and where the first outer edge ( 310 ) perpendicular to a <110> direction ( 120 ) is oriented. Silicon solar cell ( 560 . 570 ) according to one of the preceding claims, wherein the cleavage plane ( 260 ) to the surface ( 350 ) of the wafer ( 300 ) at an angle ( 140 ) extends between 50 ° and 60 °, in particular at an angle ( 140 ) of arctan √2. Photovoltaic module ( 550 ), comprising a plurality of silicon solar cells ( 560 . 570 ) according to any one of the preceding claims. Process for producing a solar cell ( 560 . 570 ) comprising the following steps: - providing a cuboid crystal ( 200 ) with an end face ( 250 ) which is at least 80% formed by a {100} plane, the crystal ( 200 ) a side surface ( 210 ), wherein a cutting line ( 390 ) of a cleavage plane ( 260 ) of the crystal ( 200 ) with the end face ( 250 ) of the crystal ( 200 ) perpendicular to the side surface ( 210 ), wherein the cleavage plane ( 260 ) with the end face ( 250 ) an angle ( 140 ) between 50 ° and 60 °; - dividing the crystal ( 200 ) to a wafer ( 300 ) with a surface ( 350 ) which is at least 80% formed by a {100} plane, wherein the wafer ( 300 ) a first outer edge ( 310 ), which from the side surface ( 210 ) is formed; - dividing the wafer ( 300 ), the dicing starting from one at the first outer edge ( 310 ) arranged predetermined breaking mark ( 370 ), whereby the dicing along the cleavage plane ( 260 ) he follows. Method according to claim 5, wherein the cleavage plane ( 260 ) is a {111} plane. Method according to one of claims 5 or 6, wherein the predetermined breaking mark ( 370 ) before dividing the crystal ( 200 ) is created. Method according to one of claims 5 to 7, wherein the predetermined breaking mark ( 370 ) after dividing the crystal ( 200 ) is created. Method according to claim 8, wherein a plurality of wafers ( 300 ) is stacked on top of each other, with all wafers ( 300 ) of the stack ( 400 ) with a break mark ( 370 ). Method according to one of claims 5 to 9, wherein the application of the predetermined breaking mark ( 370 ) by mechanical scribing or by means of a laser. Method according to one of claims 5 to 10, wherein the dicing of the wafer ( 300 ) between the break mark ( 370 ) and one at a third outer edge ( 330 ) of the wafer ( 300 ) arranged second predetermined breaking mark ( 380 ) he follows. Method according to one of claims 5 to 11, wherein prior to the dicing of the wafer ( 300 ) the following step is carried out: - producing an output solar cell ( 500 ) on the wafer ( 300 ).

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