Intrinsic stress evolution in diamond films prepared in a CH4H2NH3 hot filament chemical vapor deposition system

Abstract

Abstract The intrinsic stress in diamond films prepared in a CH 4 H 2 NH 3 hot filament chemical vapor deposition system has been investigated by the substrate curvature technique as a function of film thickness (2.2–50 μm) and ammonia concentration (0–1.4%). Our results indicated that the film stress changed from compressive to tensile with the increase of film thickness and diamond quality at a constant ammonia concentration of 0.5%. The existence of a non-diamond phase was found to be beneficial to the relaxation of intrinsic tensile stress in the films. The intrinsic stress in diamond films was tensile at an ammonia concentration from 0 to 1.4%, while the maximum tensile stress existed at 0.75% NH 3 . The possible origin of intrinsic tensile stress was discussed.