Zinc nitride films were used as an active layer in thin film transistors to assess its performance in optoelectronic applications. Those nitride layers were grown by radio-frequency magnetron sputtering in Ar/N2 ambient using a Zn target. Bottom- and top-gate thin film transistors were fabricated by photolithography processes. Transmission measurements for these particular layers showed an absorption edge around 1.3 eV. Normally off transistor characteristics with a threshold voltage of 6 V were obtained in the bottom-gate configuration without post-growth annealing. In the saturation region, those transistors produced enhanced output characteristics under illumination with infrared/visible light.