Growth of crystallized Ge films from VHF inductively-coupled plasma of H2-diluted GeH4

We have studied the Ge crystalline nucleation and film growth on quartz substrate at 250 deg. C from inductively-coupled plasma (ICP) of GeH4 diluted with H2. The ICP was generated by supplying 60 MHz power to an external single-turn antenna which was placed on a quartz plate window of a stainless steel reactor and parallel to the substrate. We have found that the growth rate is significantly increased when the preferential growth of the (110) plane becomes pronounced after the formation of randomly-oriented crystalline network. The (110) oriented Ge films, of which average crystallinity is as high as 70%. The integrated intensity ratio of TO phonons in crystalline phase to those in disordered phase, were grown at a rate of ∼ 4.0 nm/s after the formation of amorphous incubation layer with a thickness of ∼ 0.1 μm on quartz