Thermal change during formation process of indium-tin-oxide transparent conductive films

摘要

Formation of tin-doped indium oxide (indium-tin-oxide; ITO) transparent conductive films via dip coating or spin coating was investigated by TG for the precursor materials, di-n-butyltin(IV) diacetate (C4H9)(2)Sn(CH3COO)(2), tin(II) acetate Sn(CH3COO)(2) and indium diacetate monohydroxide In(OH)((CH3COO)-C-.)(2). influence of the sample mass was examined on the thermal behavior of di-n-butyltin(IV) diacetate in He-20%O-2 atmosphere. The maximum mass (60 mg) inserted in the sample pan showed a remarkable mass loss (96.9%) via a single step which was interpreted as vaporization of di-n-butyltin(IV) diacetate while the minimum mass (0.3 mg) showed less mass loss (34.5%) to produce an SnO2 film (estimated thickness, similar to 0.75 mu m) on the bottom of the sample pan. Influence of the heating atmosphere was investigated for the foregoing three compounds by fixing the sample mass to the minimum value (0.3 mg) in He-20%O-2 and He atmospheres. Mass loss due to the vaporization of the metal-containing compounds was enhanced in the He atmosphere; the mass loss was most remarkable in case of di-n-butyltin(IV) diacetate and least so in case of indium diacetate monohydroxide. The yield of the residual metal oxide increased in the He-20%O-2 atmosphere; in case of indium diacetate monohydroxide, vaporization of indium-containing compound was negligible in forming an In2O3 film (estimated thickness, similar to 0.8 mu m) on the bottom of the sample pan at 500 degrees C. Coexistence of SnO2 and SnO was observed when tin(II) acetate was heated in an oxygen-containing atmosphere. These results suggested that thermal analysis of the precursor materials should be performed with the sample mass corresponding to the film thickness. (C) 2000 Elsevier Science B.V. All rights reserved. [References: 10]