Characterization of Low Temperature P-Type Hydrogenated Microcrystalline Silicon Thin Films Deposited by Plasma Enhanced Chemical Vapor Deposition

Abstract

P-type hydrogenated microcrystalline silicon (µc-Si:H) thin films (~ 100 nm) were deposited using plasma enhanced chemical vapor deposition (PECVD) at a substrate temperature of 150 °C. RF power density and pressure were varied among films. These films reach a dark conductivity (σ d ) of 10 -1 S/cm, activation energy (E a ) of 10 -2 eV and crystalline volume fraction (X c ) of > 50 %. The structure of these films is composed of nano-sized crystallites embedded in an amorphous matrix, resulting in wide optical bandgap energies (E opt ). Using the Scherrer's formula, grain sizes were estimated to be < 20 nm.