Structural, optical and electrical properties of nanodiamond films deposited by HFCVD on borosilicate glass, fused silica and silicon at low temperature

Abstract

The addition of a small amount of oxygen to the CH4 and H-2 feed gas supports the diamond growth during hot filament assisted chemical vapor deposition (HFCVD) even at a substrate temperature below 500 degreesC. Here we present AFM, SEM, SIMS, X-ray diffraction, Raman scattering, optical transmittance spectra, PDS and temperature resolved resistivity measurements of thin B-doped,CVD diamond layers deposited on silicon, fused silica and borosilicate glass at low substrate temperatures. The Raman peak 1332 cm(-1) for diamond layers on silicon shifts towards lower (higher) values for layers deposited on fused silica (borosilicate glass) indicating a significant tensile (compressive) stress in diamond films deposited on amorphous substrates. Diamond films grown at low temperature are very smooth (the surface roughness below 10 nm) and they are optically transparent for photon energies up to 6 eV. However, they are highly resistive despite a relatively high B concentration in plasma during growth. (C) 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.