Dominant ion species in VHF SiH4/H2 plasma

Dominant ion species in VHF SiH4/H2 plasma (frequency 60 MHz) were estimated from the sheath potential and the electron temperature measured with the Langmuir probe. As the concentration of SiH4/H2 was increased, the transition of dominant ion species from H+ to SiH3+ was observed. When the discharge gap was shorter than 10 mm, measured sheath potentials were anomalously low compared with the calculated ones (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)