abstract
The overall residual stresses and the stress distribution on chemical vapor deposition diamond coated silicon nitride (Si3N4) are investigated by x-ray diffraction using the classical sin(2) psi method and the low incident beam angle diffraction technique, respectively. The deposition time and the substrate surface roughness evidence a clear effect on the film texture and residual stress generation on the diamond coatings. For the roughest substrate, 15 mum polished diamond, as the deposition time increases from 2 to 6 h, a remarkable improvement of the (220) texture and compressive stress relaxation occur from -0.75 to -0.14 GPa. A change to less compressive and even to slight tensile stress takes place for the smoothest substrate, colloidal finished silica, giving stress values of -0.40 and 0.21 GPa for 2 and 6 h of deposition time, respectively. The stress profile along the film thickness for the 6 h grown diamond film on the 15 mum polished substrate exhibits a linear decrease, in absolute values, from a compressive residual stress of -3.7 GPa, in the upper layer of the film, to almost zero stress at the film/substrate interface. (C) 2003 American Institute of Physics.
keywords
CHEMICAL-VAPOR-DEPOSITION; MICRO-RAMAN SPECTROSCOPY; THIN-FILMS; SILICON-NITRIDE; INTERNAL-STRESSES; ADHESION STRENGTH; COATINGS; MPCVD
subject category
Physics
authors
Soares, MR; Belmonte, M; Silva, RF
our authors
Maria do Rosário Teixeira Soares
Laboratory Officer