Degradation Processes in Surface Layers of Indium Oxide

作者：Fuks David L^*; Kiv Arnold E; Shapiro Dina V; Golovanov Vyacheslav V; Smatko Vasilij N; Donchev Ivan I

来源：IEEE Transactions on Device and Materials Reliability, 2012, 12(1): 133-138.

DOI：10.1109/TDMR.2011.2178244

• Degradation
• density functional theory (DFT)
• semiconductor films
• sensor systems

The degradation of In2O3 (110) surface as a working surface in the In2O3-based sensor is studied. Theoretical and experimental investigations of electronic and atomic processes on this surface caused by the adsorption of H-2 molecules are performed. In the framework of the density functional theory, we determined the energetically preferable position of the adsorbed H-2 molecule over In2O3 surface. It was found that the adsorbed H-2 molecule is mainly %26quot;bonded%26quot; with In atom. The redistribution of the electron density around In atom leads to a weakening of chemical bonds in the vicinity of In atom, and this circumstance is a reason of its destabilization. The temperature dependence of the resistance of In2O3 films in a wide interval of temperatures was measured. This dependence is characterized by a specific maximum. The obtained experimental results are interpreted using theoretical results concerning a destabilization of surface In atoms induced by the adsorbed H-2 molecules and, on the basis of our recent results in an earlier paper, concerning a high-temperature degradation of the In2O3 (110) surface layers as a working surface in sensor devices. We suggested a two-stage model of the degradation process: In the first stage, the disordering of surface caused by H-2-adsorption-stimulated displacement of In atoms leads to the increase of surface resistance, and in the second stage, displaced In atoms form precipitates and this process causes a metallization of In2O3 surface and a decrease of the resistance.

• 出版日期2012-3
• 单位中国科学院电工研究所