Inversion from selective homoepitaxy of Si to selective Si film deposition on SiO₂ using an ultraclean electron cyclotron resonance plasma

Plasma enhanced selective deposition of Si has been investigated using an ultraclean electron cyclotron resonance plasma. Selective homoepitaxy of Si without substrate heating has been achieved for the first time by decomposition of SiH₄ with a plasma generated from dilute H₂ in Ar mixtures. Moreover, the selectivity can be inverted to deposit Si films only on SiO₂ through changes in the plasma conditions. Based on the x-ray photoelectron spectroscopy analysis and experiments investigating growth with and without ion bombardment, it is concluded that competitive contributions of ion induced decomposition of SiH₄ and chemical etching with hydrogen radicals play important roles in the selectivity inversion.