Tin dioxide films prepared by dc sputtering from a pressed powder target

Abstract

Tin dioxide films were prepared by dc glow-discharge sputtering, using a target of compressed SnO2 powder. The films thus produced are conductive at room temperature (σ=3×10−5 Ω−1 cm−1). By mixing Sb2O3 powder with SnO2 powder in varying proportions, conductivity as high as 1 Ω−1 cm−1 was achieved. Conductivity and optical absorption increases with increasing Sb content. Transparency as high as 85% is obtained in doped 90-nm films on glass. An Sb2O3 content of 10% and more increases the lattice disorder of the films, thereby making them nonconducting. Such films can be made conductive by heat treatment. These films are n type and nondegenerate. The activation energy decreases with increasing antimony content.

D.C. Sputtering Process: Its Characterization and its Problems When Applied to Tin‐Dioxide Thin‐Films

“…The films deposited in argon (Ar) have been observed to be more conductive than those deposited in nitrogen (or air or oxygen). 3 The films sputtered in Ar tend to be deficient in oxygen to an extent that under certain deposition conditions the films become opaque. 2 The target surface also turns grey in color which is indicative of reduction of surface.…”

“…The type of the substrate can have an appreciable effect on the film conductivity if the deposition temperature is low (30C). 3 The conductivities of the films deposited under identical deposition conditions on glass and ceramic substrates are listed in Table I. The films on the glass substrates are more conductive than those on the ceramic substrates.…”

“…30C have small grain size and they tend to be highly resistive and unstable. 3 These films, when subjected to several temperature cycles (< 370C) become stable and highly conductive. 8 This is probably due to the enlarged grain-size and increased substitution of Sn atoms by otherwise interstitial Sb atoms.…”

D.C. sputtering process: its characterization and its problems when applied to tin-dioxide thin-films

“…3 The conductivities of the films deposited under identical deposition conditions on glass and ceramic substrates are listed in Table I. The films on the glass substrates are more conductive than those on the ceramic substrates.…”