Property of nano-thickness nickel silicides with low temperature catalytic CVD

10 nm thick Ni layers were deposited on 200 nm SiO₂/Si substrates using an e-beam evaporator. Then, 60 nm or 20 nm thick α-Si:H layers were grown at low temperature (<200°C) by a Catalytic-CVD. NiSi layers were already formed instantaneously during Cat-CVD process regardless of the thickness of the α-Si. The resulting changes in sheet resistance, microstructure, phase, chemical composition, and surface roughness with the additional rapid thermal annealing up to 500°C were examined using a four point probe, HRXRD, FE-SEM, TEM, AES, and SPM, respectively. The sheet resistance of the NiSi layer was 12Ω/□ regardless of the thickness of the α-Si and kept stable even after the additional annealing process. The thickness of the NiSi layer was 30 nm with excellent uniformity and the surface roughness was maintained under 2 nm after the annealing. Accordingly, our result implies that the low temperature Cat-CVD process with proposed films stack sequence may have more advantages than the conventional CVD process for nano scale NiSi applications.