Study of the electrical and junction properties of ITO thin films deposited on CdTe and InP substrates

Thin films of indium tin oxide (ITO) have been deposited on fused quartz su bstrates by the spray deposition and rf-magnetron sputtering methods and th eir optical and electrical properties investigated. The junction properties of fabricated ITO/pCdTe and ITO/pInP structures have also been studied and their electrical properties presented. It is established that the deposite d ITO films have a lattice constant of 10.14 Angstrom and grow in cubic mod ifications along the (400) direction. Their transmittance value rises up to between 85% and 90% and extends well beyond the visible range of the spect rum. In the forward direction of the ITO/pCdTe structure, it is suggested t hat tunnelling dominated processes determine the current flow mechanism. Re combination currents at the interface region and thermionic-emission curren ts, however, dominate in the ITO/pInP structure at low bias and high bias r espectively. The two structures can best be described as heterojunctions. ( C) 1999 Elsevier Science Ltd. All rights reserved.