Crystalline silicon sheet or strip with columnar structure prodn. - by sintering dried film of slip on reusable refractory inert support

摘要

In the prodn. of crystalline Si sheets or strips with columnar structure, esp. for making solar cells of large area, without melting the material forming the Si structure, Si powder with a granulation of under 1 micron and opt. additives is made into a slip with a binder. The slip is spread into a film on a support and dried and the support is removed. Then the film is sintered on a refractory inert support in a protective gas atmos. below 1430 deg.C, so that a layer of monocrystalline Si grains with a dia. matching the thickness of the film is formed. The novel feature is that a re-usable inert support of a material insensitive to frequent heating and cooling is used. The inert support consists of sintered alumina, Mo, mullite or graphite, esp. with a pyrolytic coating. The process is more economical than previously.