Method of preparing solar cell front contacts
AssigneeImec Vzw
InventorsJozef Szlufcik, Johan Nijs, Roland Jozef Fick
Life of this patent
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Abstract
Method of preparing on a solar cell the top contact pattern which consists of a set of parallel narrow finger lines and wide collector lines deposited essentially at right angles to the finger lines on the semiconductor substrate, characterized in that it comprises at least the following steps: (a) screen printing and drying the set of contact finger lines; (b) printing and drying the wide collector lines on the top of the set of finger lines in a subsequent step; (c) firing both finger lines and collector lines in a single final step in order to form an ohmic contact between the finger lines and the semiconductor substrate and between the finger lines and the wide collector lines.
Claims13
A method of preparing a contact pattern on a semiconductor substrate of a solar cell, said pattern comprising a set of narrow finger lines and wide collector lines that intersect and that are in electrical contact, said method comprising the steps of:
- (1) screen printing a masking paste on top of a front surface of said semiconductor substrate using a screen with a pattern structure, thereby forming a printed pattern;
- (2) depositing a coating over said front surface;
- (3) dissolving said masking paste whereby selectively lifting-off the part of the coating deposited on top of the masking paste;
- thereafter
- (4) etching off oxide layers from areas of said front surface exposed through openings in the coating, wherein said openings are formed through the dissolving and lift-off step (3);
- and thereafter
- (5) screen printing the set of finger lines in said openings formed in said coating using a screen with said pattern structure and drying the set of finger lines.
Dependencies are inferred from the claim text.