The growth mechanism of Ge1−x-Cx:H films deposited by PECVD method

摘要: Abstract In the current study, Ge1−x-Cx:H films were deposited on silicon and glass substrates by a plasma-enhanced chemical vapor deposition (PECVD) process with gas mixture of GeH4 CH4 as precursors. For characterizing films, field emission scanning electron microscopy (FESEM), atomic force (AFM), Rutherford backscattering spectrometry, elastic recoil detection analysis, adhesion test used. Based results, growth mechanism PECVD was suggested three separate steps including 1) removal surface H formation dangling bonds, 2) insertion germanium methane radicals into bonds 3) inter-atomic Ge Ge, C transverse respectively. If in environment XH3 (X = Ge, C) be dominant radicals, two-dimensional occurs. On other hand, presence variety radical species (XH3, XH2, XH) results preferred three-dimensional growth. With increasing CH4: flow rate ratio, homogenization ions becomes more prevalent consequently, tends to