Electronic and Optical Properties of a-Si:H Films Alloyed with Sulfur

Abstract

ABSTRACTAlloying a-Si:H with small amounts of sulfur (≤ 4 × 1020 cm−3) results in a significant enhancement in the photoconductivity and a suppression of the optically-induced degradation of the photoconductivity (Staebler-Wronski effect). The Magnitudes of the activation energies for conductivity imply that these films remain essentially intrinsic in nature. When the sulfur concentration is increased to about 2 to 3 at. %, the Fermi level rises by about 0.25 eV, a fact that suggests that sulfur may act as a very inefficient dopant in a-Si:H.