Influence of (CH3)(2)NHBH3 concentration on electrical properties of electrochemically grown ZnO films

Zinc oxide (ZnO) films have been deposited on nonconductive glass substrate s by chemical deposition followed by electrochemical growth in zinc nitrate [Zn(NO3)(2).H2O] aqueous solutions containing dimethylamine-borane (DMAB) at 333 K. The effect of DMAB; concentration on the structural and electrica l characteristics was investigated by inductively coupled plasma analysis. X-ray diffraction, and Hall measurement. The increase in DMAB concentration gave a decrease in resistivity and an increase in carrier concentration an d mobility. The boron content in the ZnO film increased with an increase in DMAB concentration. The 1.5 mum thick ZnO film with a maximum boron conten t of 1.1 atom % was obtained at the cathodic potential of -0.8 V from a 0.1 mol/L zinc nitrate aqueous solution with 0.1 mol/L DMAB. This film had a r esistivity of 7.8 x 10(-3) Omega cm, carrier concentration of 1.2 x 10(19) cm(-3), and mobility of 86 cm(2) V-1 s(-1). Boron ions originating from DMA B acted as donors for the ZnO film and gave the lattice expansion. (C) 2001 The Electrochemical Society.