Preparation of µc-Si:H/a-Si:H Multilayers and Their Optoelectric Properties

Abstract
A layered structure consisting of alternate sublayers of µc-Si:H and a-Si:H was fabricated by means of plasma enhanced CVD from fluorinated precursors, SiH n F m (n+m≤3), under the condition modified periodically by the addition of SiH n as an amorphousizing agent. The structure with repeated layers of 75 Å or less in thickness was confirmed by small-angle X-ray diffraction. High photoconductivity equivalent to that of a-Si:H was maintained in the layered structures in the period of 75 Å or less despite the marked increase in optical absorption in the near-IR region of 1.0 eV–1.5 eV resulting from the optical absorption of the µc-Si:H layers.