GaN Epitaxy: How to Characterize Hazards for the Operators

Abstract

In the framework of the European AGETHA research program semiconductors based on AlGaN/GaN/GaInN materials are deposited by MOCVD (Metal Organic Chemical Vapor Deposition) to prepare amber and green emitters for automotive and avionics applications. Very little is known of the toxicity of gallium and indium compounds. Consequently there is a need for analytical measurements in order to determine and minimize the risks for operators. Dust and gaseous molecules can be released when preventive maintenance is done on the MOCVD machine (deposition chamber, pumping group, main maintenance) or when the substrate is loaded into the reaction chamber. A bibliographic search has been done on the toxicology of gallium and indium compounds. A short summary of what is known on the toxicity of the various molecules and their effect on the target organs is presented. Experimental measurements related to pollutants emitted during maintenance are reported.