Crystallisation Phenomena of In2O3:H Films

The crystallisation of sputter-deposited, amorphous In2O3:H films was investigated. The influence of deposition and crystallisation parameters onto crystallinity and electron hall mobility was explored. Significant precipitation of metallic indium was discovered in the crystallised films by electron energy loss spectroscopy. Melting of metallic indium at 160 degrees C ws suggested to promote primry crystllistion of the morphous In2O3:H films. The presence of hydroxyl ws scribed to be responsible for the recrystlliztion nd grin growth ccompnying the inter-grin In-O-In bounding. Metllic indium ws suggested to provide n excess of free electrons in s-deposited In2O3 nd In2O3:H films. ccording to the ultrviolet photoelectron spectroscopy, the work function of In2O3:H incresed during crystllistion from 4 eV to 4.4 eV, which corresponds to the oxidtion process. Furthermore, trnsprency simultneously incresed in the infrredspectrl region. Wter ws queried to oxidise metllic indium in UHV t higher temperture s compred to oxygen in mbient ir. Secondry ion mss-spectroscopy results reveled tht the former process tkes plce mostly within the top 50 nm. The opticl bnd gp of In2O3:H incresed by bout 0.2 eV during nneling, indicting doping effect. This ws considered s likely intr-grin phenomenon cused by both (In-0)(O)(center dot center dot) nd (OH-)(O)(center dot) point defects. The inconsistencies in understnding of In2O3:H crystllistion, which existed in the literture so fr, were considered nd explined by the multiplicity nd disequilibrium of the processes running simultneously.