MEASUREMENT OF RESIDUAL-STRESS IN DIAMOND FILMS OBTAINED USING CHEMICAL-VAPOR-DEPOSITION

Diamond films were deposited on a p-type Si substrate using the hot fi lament chemical vapor deposition (HFCVD) method. Residual stresses in the films were subsequently measured using the curvature, the X-ray di ffraction (XRD) sin(2) psi, and the Raman peak shift methods. Results from the three methods were in agreement and indicated that residual s tresses changed from compressive to tensile with increasing film thick ness, bur the maximum or minimum extent of the stresses measured by th e Raman and XRD methods was 3-5 times larger than those by the curvatu re method. These results were correlated with the results from the det ermination of Young`s modulus and total peak shifts by the XRD and the Raman methods. Young's moduli of diamond films were measured by the s onic resonance method, and the peak shift due to residual stress was s eparated from the total peak shift using the beam bending theory. Afte r the adjustment, the disparity among the stress measurements was sign ificantly reduced and a stress range of -0.5 GPa to +0.5 GPa was obtai ned.