METHOD FOR FORMING THIN SEMICONDUCTOR LAYER SUBSTRATES AND METHOD FOR PRODUCING A SEMICONDUCTOR ELEMENT, IN PARTICULAR A SOLAR CELL COMPRISING, USING SAID TYPE OF SEMICONDUCTOR LAYER SUBSTRATE

摘要

The invention relates to a method for forming thin semiconductor layer substrates, wherein low porous layers (33, 37) and highly porous layers (35, 39) are formed in an alternating manner in a semiconductor substrate (1) by electrochemical etching. The thus obtained multi-layer stack can subsequently be subjected, in its totality, to additional treatment steps. For example, a passivation dielectric layer (45) can be formed on the entire surface of the low porous layers (33, 37) and the highly porous layers (35, 39). Subsequently, the low porous layers can be successively separated from each other in a mechanical manner, the highly porous layers arranged therebetween acting as a desired rupture point. It is also possible to form, in a few steps, a plurality of thin semiconductor layer substrates in the form of low porous layers (33, 37) and to obtain a good surface passivation and a reflection-reducing surface texture. The thus produced semiconductor layer substrates can be used, for example, for producing semiconductor elements, for example thin solar cells.