Residual stresses in chemical vapour deposited diamond films

In this paper we report the determination of residual stresses in diamond films grown on Si(100) using a plate bending theory and a hi-metal theory combined with micro-Raman spectroscopy. Raman spectra show that with an increase in the film thickness, the characteristic diamond line shifts from higher wave numbers (> 1332 cm(-1)) to lower (< 1332 cm(-1)), indicating a change of compressive to tensile bi-axial stress with increase in the film thickness. A plate bending theory and a bi-metal theory are used to determine the distribution of the stress induced by the thermal mismatch. The modelled results show that the bi-axial stress decreases linearly along the film growth direction and the stress at the film/substrate interface decreases when the film becomes thicker. The difference from the Raman results is attributed to intrinsic stress. (C) 2000 Elsevier Science S.A. All rights reserved.