Ti/Au Ohmic contacts to indium zinc oxide thin films on paper substrates

Abstract

Low resistance Ohmic contacts using Ti/Au metallization on n-type amorphous indium zinc oxide (IZO) (n∼5×1020 cm−3) deposited on paper substrates are reported. The minimum specific contact resistivity of 8×10−7 Ω cm2 was achieved on IZO films both as-deposited and for annealing temperatures of up to 125 °C. The contact resistance increased to 4×10−6 Ω cm2 at 175 °C. The sheet resistance was found to vary from 24 to 17 Ω/sq, and the transfer resistance was ∼0.045 Ω mm for the as-deposited and low temperature annealed samples. The contact resistance was independent of measurement temperature, indicating that field emission plays a dominant role in the current transport. Such Ohmic contacts achieved with little or no annealing are important for paper based electronics requiring low temperature processing (<200 °C).