Intrinsic stress evolution in nanocrystalline diamond thin films with deposition temperature

The stress evolution in nanocrystalline diamond (NCD) films deposited at different temperatures (from 800 to 400 degrees C) was investigated. Results showed that the intrinsic stress gradually changed from tensile to compressive with decreasing deposition temperature. Most importantly, the intrinsic stress can be tailored to zero by adjusting the deposition temperature, which is critical to many applications. It has been proven that more H as well as sp(2) bonded carbon was incorporated into the grain boundaries, which was responsible for the evolution of stress and other mechanical properties with deposition temperature. Moreover, all the NCD films showed excellent mechanical properties. (C) 2008 American Institute of Physics.