The dependency of sputtering power on the electrical performances in amorphous HIZO-TFT (hafnium-indium-zinc-oxide thin film transistors) has been investigated. The HIZO channel layers were prepared by using radio frequency (RF) magnetron sputtering method with different sputtering power at room temperature. TOF-SIMS (time of flight secondary ion mass spectrometry) was performed to confirm doping of hafnium atom in IZO film. The field effect mobility (μFE) increased and threshold voltage (Vth) shifted to negative direction with increasing sputtering power. This result can be attributed to the high energy particles knocking-out oxygen atoms. As a result, oxygen vacancies generated in HIZO channel layer with increasing sputtering power resulted in negative shift in Vth and increase in on-current.

The semiconducting material of ZnO in II-VI group was well known as its good application for photo electronics, chemical sensors and field effect transistors due to the remarkable optical properties with wide energy band gap and great ionic reactivities. Up to now the growth of a good quality of ZnO film has been issued for better performances. Even though there were many deposition methods for making ZnO films, pulse laser deposition methods have been preferred for high crystalline films. In this report, the ZnO film was also created by pulsed laser deposition technique which also showed high crystalinity. By controlling several factors when deposited, it was investigated that the optimal condition for ZnO film formation. Mainly, oxygen partial pressures and growth temperatures were changed when ZnO films were synthesized and followed the characterization by HRXRD and AFM.