Indium-tin-oxide thin films prepared by dip-coating of indium diacetate monohydroxide and tin dichloride

Tin-doped In2O3 (ITO) films were prepared by the dip-coating method using an ethanol solution of indium diacetate monohydroxide, In(OH)(CH3COO)(2), and tin dichloride. SnCl2. 2H(2)O, with 2-aminoethanol (monoethanolamine), H2NC2H4OH. The influence of the tin concentration was investigated between 0 and 20 at.% Sn. The composition of the films (thickness similar to 90 nm) approximately agreed with that of the solution when the dipping and the heating at 600 degreesC in air for 30 min were repeated three times. The lattice constant of the ITO films increased by the tin addition and annealing at 600 degreesC for 1 h in a nitrogen flow. The films were highly transparent in the visible range. At 6.4 at.% Sn, the maximum carrier concentration (6.2 X 10(20) cm(-3)) and minimum resistivity (5.8 X 10(-4) Omega cm) were obtained after annealing in nitrogen (oxygen partial pressure similar to 2.0 Pa). The mobilities of the ITO films (similar to 10 cm(2) V-1 s(-1)) were almost independent of the film composition and the annealing, The mobilities of the undoped In2O3 films were similar to 40 cm(2) V-1 s(-1). (C) 2001 Published by Elsevier Science B.V. All rights reserved.