TRANSPARENT ARCPROOF PROTECTIVE COATINGS: PERFORMANCE AND MANUFACTURABILITY ISSUES

摘要

Highly transparent thin films with moderately high sheet resistivity approximately 10~8 ohms-square~(-1) (Ω·□~(-1)) are needed for protection of photovoltaic arrays and other spacecraft surfaces from static charging in space. They may also be useful for dust control on Mars and the Moon. Indium tin oxide (ITO) codeposited with the transparent insulator MgF_2 is promising for these applications, but it is difficult to deposit films with reproducible sheet resistivity. We report experiments on a small dual RF magnetron sputter coater, using plasma emission monitoring (PEM) to improve control of film composition. Results show that PEM is useful for composition control but must be supplemented by periodic in situ measurements of coatings' optical or electrical properties. We have successfully coated both rigid (glass, quartz) and flexible substrates.