GROWTH OF AMORPHOUS ZINC PHOSPHIDE FILMS BY REACTIVE RADIO-FREQUENCY SPUTTERING

Thin zinc phosphide films were grown by reactive radio frequency sputt ering of pure zinc in a phosphine containing argon atmosphere. The inf luence of the deposition parameters and the substrate on film composit ion and structure was investigated. A prominent change of the growth w as noticed between deposition at room temperature and higher temperatu res due to the high vapor pressure of zinc. For substrate temperatures above 100 degrees C a range of the r.f. power exists for which the sy stem is self limiting. In this regime the phosphine mass flow is the r ate limiting quantity, and the growth of non-crystalline and polycryst alline stoichiometric Zn3P2 films is possible over a large range of r. f. power.