DFG Research Unit 2857

Copper Iodide as Multifunctional Semiconductor

P02: Chemical Routes to CuI Thin Films and Bulk Material

Prof. Dr. Harald Krautscheid

Copper iodide, CuI, is a wide bandgap p-type conducting material with high hole conductivity. In addition, CuI is transparent in the visible spectral range. Therefore, CuI thin films and single crystals are interesting materials for electronic applications. Within the Research Unit FOR 2857, this project focuses on the development of chemical methods for preparation of CuI thin films and bulk crystals with defined properties. It aims at understanding of nucleation and growth mechanisms of thin films, investigation of structural defects and optimization of layer homogeneity and surface morphology. For CuI deposition as crystalline thin films and as epitactic layers on substrates, metal-organic chemical vapor deposition (MOCVD) and close distance sublimation (CDS) methods will be developed. Fundamental studies concern the influence of copper and iodine sources, substrate materials, synthesis conditions and incorporation of dopants on the microstructure and optical and electrical properties of the CuI thin films. Eventually, defined n-p heterojunctions between CuI and n-type semiconductors will be generated. For synthesis of pure and doped CuI single crystals, growth from solution and by sublimation methods will be investigated in order to obtain strainless crystals.