Microstructure and morphology evolution in chemically deposited semiconductor films: 4. From isolated nanoparticles to monocrystalline PbS thin films on GaAs(100) substrates

Department of Materials Engineering and the Ilse Katz Center for Nanoscience and Nanotechnology, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel

Corresponding author: ygolan@bgu.ac.il

Received: 2 July 2006
Revised: 9 October 2006
Accepted: 12 October 2006
Published online: 13 December 2006

Abstract

Thin lead sulfide films were grown on single crystal GaAs(100) substrates by chemical deposition using Pb(NO₃)₂ and CS(NH₂)₂ with excess of NaOH in aqueous solution at a range of deposition temperatures 0–50 °C. The microstructure and morphology evolution were studied as a function of the deposition conditions, resulting in a wide range of microstructures. Ultrahigh resolution scanning electron microscopy and atomic force microscopy indicated a systematic change in particle shape and surface morphology as a function of deposition temperature and deposition time. X-ray diffraction of 200–500 nm thick films indicated a dominant texture throughout the deposition temperature range. At deposition temperatures above 40 °C, single crystal films were obtained. Cross-sectional transmission electron microscopy analyses showed a unique (011)_PbS||(100)_GaAs and [100]_PbS||[011]_GaAs orientation relationship.