Structural studies on Si:H network by Raman, micro-photoluminescence, electron microscopy and ultraviolet ellipsometry: effect of Ar dilution to the SiH4-plasma

Abstract Structural characterization of the material has been performed using micro-Raman spectroscopy, ultraviolet (UV) ellipsometry, electron microscopy and micro-photoluminescence (PL) studies on Si:H films prepared at a wide range of Ar dilution to the SiH 4 plasma, defined by R(Ar)=Ar/SiH 4 and varying from 10 to 400. Microcrystallization in Si:H network was easily obtained introducing Ar as a diluent, however, increasing Ar dilution revealed a continuous transformation of the network from microcrystalline to amorphous dominated structure. An overall amorphization of the network and its initiation by the presence of an enormously high void density (∼81 vol.%) in an extended incubation layer (∼163 nm) is the result of extremely high Ar dilution (R(Ar)∼400), on the formation of Si:H films. Increasing porosity in the amorphous dominated matrix resulted in a significant increase in the photoluminescence intensity, contributing to a photoluminescent Si:H material available from extremely high Ar dilution to the SiH 4 plasma in rf glow discharge. Effect of Ar dilution inducing the growth morphology by controlling both the gas phase reactions and solid phase network modifications in Si:H network has been discussed.