Monocrystalline powder and monograin membrane production

摘要

For production of monocrystalline powders there is formed a melt to which a fluxing agent is added. The melt contains the components of a semiconductor material, an example being the components of copper indium diselenide which are generally used in a stoichiometric composition. The melt is usually heated to temperatures of between 300° C. and 1000° C. Monocrystalline powder grains grow. The desired recrystallization takes place at temperatures above the melting points of the materials to be fused. Once the powder grains have the desired size, the growth is stopped by quenching. The appropriate instant of quenching as well as the appropriate temperature profile for obtaining desired powder sizes are determined by, for example, preliminary experiments. Thereafter the fluxing agent is eliminated. Monograin membranes are produced from the powders produced according to the process and are used in particular in solar cells. The process is simple and inexpensive. Powder grains of uniform size are obtained.