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

Low resistance Ohmic contacts using Ti/Au metallization on n-type amorphous indium zinc oxide (IZO) (n similar to 5 x 10(20) cm(-3)) deposited on paper substrates are reported. The minimum specific contact resistivity of 8 x 10(-7) Omega cm(2) was achieved on IZO films both as-deposited and for annealing temperatures of up to 125 degrees C. The contact resistance increased to 4 x 10(-6) Omega cm(2) at 175 degrees C. The sheet resistance was found to vary from 24 to 17 Omega/sq, and the transfer resistance was similar to 0.045 Omega 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 degrees C) . (C) 2010 American Vacuum Society. [DOI: 10.1116/1.3467507]