Spray-coated crystalline InZnOx-based semiconductors are investigated as a function of [In3+]:[Zn2+] and their performance as TFTs semiconducting channels. More precisely, it is demonstrated that optical, structural, and electron transport properties show a high degree of sensitivity to the films' stoichiometry; that is, the [In3+]:[Zn2+] atomic ratio that equally determines the amorphous or crystalline structure of the film. Yttrium co-doping of InZnOx with [In3+]:[Zn2+] atomic ratio of 6:4 shows that the YInZnOx structure and the key TFT parameters can further be engineered and improved in terms of the on-to-off current modulation ratio and, most importantly, the field effect mobility. It is finally demonstrated that the latter is in excess of 52 cm(2) V-1 s(-1) by combining crystalline YInZnOx and spray-coated MgO dielectrics. These results identify spray-coated crystalline YInZnOx as a viable TFT semiconducting channel material with respect to enhanced electrical performance and processing requirements in terms of simplicity and cost.