Dimethylindium tert-butoxide InMe2OtBu (and for comparison In(acac)3, In(thd)3 and as Sn precursors dibutyltindiacetate (DBTDA) and Sn(acac)2) was
investigated as precursor for the growth of tin doped indium oxide (ITO-Sn) layers by pulsed MOCVD. Differences in electrical properties of ITO layers are found when using InMe2OtBu, as compared to In(acac)3 and to In(tmhd)3: InMe2OtBu-prepared ITO-Sn layers grown at 350-700°C presented a constant resistivity. Optimal doping conditions
for ITO layers were determined based on optical and electrical characterization data. The best ITO-Sn films grown at high temperatures (T ⩾
600 °C) demonstrated transmittance higher than 84% and resistivity of 2.5 × 10−4 Ω cm. Optimal Sn-doping using DBTDA was at 8 at.% (close to the Sn solubility limit in In2O3 matrix), however with Sn(acac)2, or In(acac)3/DBTDA combination,
best functional characteristics were obtained for the maximal doping obtained (2.5 at.%). For optimal growth conditions, the resistivity decreased when deposition temperature increased (except for the InMe2OtBu/DBTDA combination without O2 addition during
deposition – for which resistivity of 1 × 10−3 Ω cm was obtained at a deposition temperature of 350 °C and stayed constant to 600 °C). Only the films obtained from InMe2OtBu/DBTDA were crystalline at a deposition temperature
of 350 °C.[[i]]
[i] P.D. Szkutnik, H. Roussel, V. Lahootun, X. Mescot, F. Weiss, C. Jiménez , J. Alloys Comp., 2014, Vol. 603, p.268-273, https://doi.org/10.1016/j.jallcom.2014.03.088, « Study of the functional properties of ITO grown by metalorganic chemical vapor deposition from different indium and tin precursors »