METHOD OF PRODUCING HIGH-PURITY CHEMICALS USING GaAs GATTER WAFERS
Original Publication Date: 1988-Apr-01
Included in the Prior Art Database: 2005-Feb-15
The chemicals are brought into intensive contact with GaAs layers 2 which are epitaxially deposited on roughly sawed silicon wafers 1 (the figure showing a perspective of a wafer section). The purification effect is based on the large surface area and the very dense dislocation network of the GaAs layer. The dislocations are caused by heteroepitaxial misfit, and their density considerably exceeds that of common semiconductive single crystals. The method is applicable to liquids, including aggressive materials, such as WF6, HF and NH4F, as well as gases, whose treatment, performed immediately before use, takes only seconds.