XPS ANALYSIS OF THIN CHROMIUM FILMS

The surface and mechanical properties of thin Cr films play an essential role in microphotolithographic processes in which an inorganic photoresist based on vacuum-evaporated As2S3 is used as a light-sensitive system. The present paper reports some XPS data about thin chromium layers obtained by thermal evaporation, high-frequency sputtering, electron beam evaporation and dc magnetron sputtering. A correlation is found between the surface elemental composition of the metal coating and the possibilities of obtaining good adhesion between the Cr and As2S3 used as the inorganic photoresist. It is shown that the presence of pure Cr on the surface of the samples is a defining condition for photolithography in the submicron region.