Effects of dc substrate bias on the properties of rf‐sputtered amorphous germanium ditelluride films

Autor: R. S. Nowicki, R. W. Seguin, E. A. Fagen
Rok vydání: 1974
Předmět:
Zdroj: Journal of Applied Physics. 45:50-59
ISSN: 1089-7550
0021-8979
DOI: 10.1063/1.1663015
Popis: We have studied the changes in chemical composition, capture and release of argon, electrical conductivity, and morphology of crystallization which result from changes in dc bias applied to the substrate during the rf sputtering of amorphous thin films of nominally stoichiometric GeTe2. We find (i) a strong increase of Te deficiency with negative bias, (ii) a strong increase in incorporated argon content with negative bias, (iii) a strong correlation between Te deficiency and argon content, (iv) no dependence of argon content on film thickness, (v) violent release of argon under certain circumstances, (vi) scant correlation between argon content and electrical properties, (vii) slightly stronger correlation between compositional variation and electrical properties, (viii) a residuum of unexplained variation in electrical properties, and (ix) morphological variations consistent with departures from stoichiometry. We conclude that the rare‐gas content of nonreactively sputtered chalcogenide alloys is largely inactive except insofar as it determines the kinetics of its own release at elevated temperatures, but that control of substrate potential during deposition is nevertheless essential for the attainment of quantitatively reproducible transport properties.
Databáze: OpenAIRE