Method for forming a functional deposited film by bias sputtering process at a relatively low substrate temperature

A process for forming a functional epitaxial film on a substrate by a bias sputtering method comprising generating a plasma of a sputtering gas between a target electrode having a target thereon and a substrate electrode having a substrate for film formation thereon in a vacuum vessel with the use of a high frequency energy with a frequency of 50 MHz to 300 MHz from a high frequency power source and sputtering said target with said plasma while applying a direct current voltage from a direct current power source to at least one of said target electrode and said substrate electrode thereby causing the formation of a film on said substrate, wherein a deposition step and a non-deposition step are alternately repeated, said deposition step comprising sputtering said target with said plasma while irradiating said substrate with ions of said plasma while depositing a film on said substrate, and said non-deposition step comprising irradiating said substrate with ions of said plasma without sputtering said target, thereby forming a high quality functional epitaxial film on said substrate.