Sn‐doped ZnO thin‐film transistors with AZO, TZO and Al heterojunction source/drain contacts

Abstract

Bottom gate, top contact thin-film transistors (TFTs) with transparent Sn-doped zinc oxide as the active layer have been fabricated on glass substrate at room temperature. Indium tin oxide, alumni zinc oxide (AZO) and Al thin films serve as the source/drain (S/D) electrode. It turns out that devices with AZO S/D electrodes exhibit preferable properties such as a saturation mobility of 13.6 cm2/Vs, a subthreshold slope of 381 mV/decade, a Vth of 3.47 V and an on/off current ratio of 3.1 × 107. Moreover, the superior output characteristic and lower parasitic resistance demonstrate the excellent contact performance of the tin-zinc oxide TFTs with AZO S/D electrodes.