SPUTTERED INSULATOR FILM CONTOURING OVER SUBSTRATE TOPOGRAPHY

Coverage of metal line patterns with rf-sputtered SiO//2, Si//3N//4, and Al//2O//3 has been investigated. The variation of step coverage with the degree of film resputtering has been studied using optical and scanning electron microscopy of both fractured and polished sections. The observed contouring is controlled by the geometry of the substrate topography and the amount of resputtering of the depositing material. Resputtering was controlled during deposition by applying rf bias voltage to the substrate electrode.