|학술대회||2013년 봄 (05/23 ~ 05/24, 여수 엠블호텔(THE MVL))|
|발표분야||F. 광기능/디스플레이 재료(Optical Functional and Display Materials)|
|제목||The study of Hf doping effect for device stability of ZTO base oxide|
|초록||Recently the study for new oxide semiconductor having characteristics such as high mobility, excellent gate swing and transparency to visible light has been accomplished. Specially, a-IGZO oxide semiconductor has been intensively studied as candidate for a suitable material for low power consumption LCD and backplane of AMOLED because of lower process capability and good uniformity for large sized panel. But the increase of manufacturing cost due to lack of indium or gallium element supply should be solved. In order to solve such a problem, the development of ZnO based oxide semiconductor and application for transparent field effect transistors has been carried out. However, ZnO based oxide semiconductor still has a limitation of device stability.
In this study, the application and optimization of ZnO based oxide semiconductor which controlled a carrier density by oxygen contents has been investigated. And the stability of Hf doped ZTO oxide semiconductor has been verified.
The ZTO channel layer (thickness:40nm) was deposited by DC magnetron sputtering in the condition, power density: 0.5 w/cm2, working pressure:5 x 10-3Torr, O2 ratio:0~40%. Then electrical TFT characteristics were measured with an HP 4155A semiconductor parameter analyzer after annealed at 400 ℃, 1hr. the electron field effect mobility is estimated to 10.45 cm/Vs. and the threshold swing and current on/off ration is found to be 0.89 V/decade, 1.1x 10-9. Meanwhile, optimized Hf (0.5 at%) doped ZTO transistors exhibited a field effect mobility:14.33cm/Vs, ION/IOFF: 1.65x109, sub-threshold swing: 0.609 V/decade, turn on voltage:3 V.
|저자||이상호, 한동석, 강유진, 박종완|
|키워드||ZTO oxide semiconductor; TFT characteristics; NBTI|