High performance IZO:P/IZO:Ni thin film transistor with double active layers

Abstract

Staggered bottom-gate thin film transistor (TFT) with double active layers was successfully fabricated. IZO:P/IZO:Ni thin films were deposited on SiO2/p-Si substrate by radio frequency (RF) magnetron sputtering, IZO:P/IZO:Ni acted as double active layers. The optical transmittance of IZO: P and IZO:Ni thin films were over 80% in the wavelength of 400–800 nm. X-ray diffraction (XRD) patterns exhibited that the IZO:P and IZO:Ni films were amorphous under the annealing temperature of 265 ℃. Atomic force microscopy (AFM) images showed that IZO:P and IZO:Ni thin films had a low root-mean-square (RMS) roughness of 0.44 nm and 0.45 nm, respectively. The annealing temperature was 265 ℃, the obtained TFT with IZO:P/IZO:Ni double active layers structure showed excellent electrical properties, including a saturation mobility of 44.5 cm2 v−1 s−1, a threshold voltage of 1.3 V, a subthreshold swing of 0.35 V/dec, and an on/off current ratio of 3.8 × 108.