Growth process and structural disorder of reactively-sputtered a-Si:H/a-SiNx multilayer films

First observation is reported of the deposition rate dependence of Raman-detected structural disorder in a-Si:H/a-SiNx semiconductor superlattices. FWHM of TO-like Raman peak of a-Si (H-free) as well as a-Si:H becomes narrow with a decrease in the deposition rate, but the narrowing in a-Si:H occurs more rapidly compared to that in a-Si. It suggests that hydrogen coverage over the growing surface does enhance the structural relaxation velocity of disordered network. It is also demonstrated that structure-relaxation time of the order of a second is included in the growth of a-Si:H/a-SiNx multilayer structures.