Amorphous SiNx:H (ahyphen;SiNx:H) films were deposited at 300thinsp;deg;C on singlehyphen;crystal Si and fused quartz substrates using SiH4hyphen;NH3mixtures. The stress and vibrational absorption were investigated as a function of the N contentx. Increased tensile stress subsequent to a reduction in the compressive stress with increasingxwas observed. From the values of stress determined for films on two different substrates, values ofY/(1minus;ngr;) forahyphen;SiNx:H films were estimated, whereYis Youngrsquo;s modulus and ngr; the Poisson ratio. The values ofY/(1minus;ngr;) rapidly decreased with an increase inx, from 4.2times;1012dyn/cm2forahyphen;Si:H films to about 2.5times;1011dyn/cm2forahyphen;SiNx:H films havingxabove 1.0. It was found that the measured tensile stress inahyphen;SiNx:H films for highxabove 1.0 was caused by the intrinsic stress, and that incorporated NH bonds act to relax the intrinsic stress. These results were discussed in terms of the change in the bonding configuration as a function ofx, based on a modified random bonding model.
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