Microstructures of ITO films deposited by d.c. magnetron sputtering with H2O introduction

ITO films were deposited by d.c. magnetron sputtering with/without H2O introduction. The structural and optoelectrical properties of the films were analyzed in detail. The films deposited with H2O introduction exhibited an entirely amorphous structure, whereas the as-deposited films deposited without H2O introduction exhibited a polycrystalline In2O3 structure. The amorphous ITO films deposited under the high H2O partial pressure were confirmed to contain a much higher concentration of hydrogen inside the films by secondary ion mass spectroscopy, which remained after post-annealing at 350 degreesC. The crystallization temperature of the films subjected to post-annealing was increased to higher than 220 degreesC. These stable amorphous ITO films had a wet-etching rate in oxalic acid solution two orders of magnitude higher than that of the films deposited without H2O introduction. (C) 2003 Elsevier Science B.V. All rights reserved.