Epitaxial growth of silicon at low temperature by ultrahigh vacuum electron cyclotron resonance plasma chemical vapor deposition

Publisher Website
Google Scholar
Abstract
Epitaxial growth of a silicon thin film has been accomplished at a temperature lower than 650 °C by electron cyclotron resonance plasma chemical vapor deposition using an ultrahigh vacuum chamber. Ar plasma from the same electron cyclotron plasma ion source is also used for surface cleaning of the substrate. The relationship between the cleaning condition of a substrate and the quality of an epitaxially grown silicon film is examined in detail. The energy of Ar plasma in the cleaning process should be kept lower than 100 eV in order to obtain films of good crystal quality. Otherwise, damage by Ar ion bombardment cannot be restored by annealing at lower than 700 °C. The epitaxial growth also should be carried out without the accelerating bias voltage to avoid residual compressive stress in the film. An epitaxial film with perfect crystal structure (indicating only a Kikuchi pattern of reflection of high-energy electron diffraction) is obtained at the substrate temperature of 710 °C.