Optical emission spectroscopy study toward high rate growth of microcrystalline silicon

A systematic optical emission spectroscopy (OES) study was carried out to enhance the deposition rate of microcrystalline silicon (μc-Si:H) with conventional r.f. plasma-enhanced chemical vapor deposition (r.f. PECVD). Among the various plasma parameters, the combination of total pressure, r.f. power, electrode distance and cathode heating was effective to promote the deposition rate without deteriorating the film crystallinity. Strong correlations among the OES intensity, SiH, intensity ratio, IHα/ISi*, deposition rate and Raman intensity ratio, Iμc-Si/Ia-Si were confirmed in the case of r.f. SiH4 and H2 PECVD. A relatively high deposition rate was achieved of ∼5 Å/s in the μc-Si:H film growth by optimizing the deposition parameters. The effects of higher pressure, higher r.f. power, inter electrode distance and cathode heating (SiH4 gas heating) are demonstrated in the growth of μc-Si:H from strong H2-diluted SiH4 by a conventional r.f. glow discharge.