TY - GEN
T1 - Structural and electrical characteristics of lanthanum oxide gate dielectric film on GaAs pHEMT technology
AU - Tsai, Wan Cheng
AU - Chen, Chao Hung
AU - Chiu, Hsien Chin
AU - Fu, Jeffrey S.
PY - 2008
Y1 - 2008
N2 - In this study, a high dielectric constant lanthanum oxide thin film (La2O3) was fabricated as a gate dielectric on GaAs pHEMTs to reduce the effect of the gate leakage caused by continuing the constant field-scaling trend of MOS technology. The chemical compositions and the crystalline structure at different annealing temperatures were observed by X-ray photoelectron spectroscopy (XPS) and x-ray diffraction (XRD) respectively, and the results reveal its significant thermal stability. By fabricating the capacitor, the dielectric constant of La2O3 with annealing at 400μ was calculated to be 21.6 which is higher than the sample without annealing. In addition, transistors with two different gate materials were successfully fabricated, Pt/La2O3/Ti/Au gate and the conventional Pt/Ti/Au gate. The DC results shown the oxide-device performed higher turn-on and breakdown voltage, exhibited better RF characteristic, and the gate leakage current was at least one order lower than the conventional device. Therefore, La2O3 is a potential candidate high-k material as the gate dielectric which can enhance the performance while scaling down the device dimension and overcome the thermal effect applied for high power applications.
AB - In this study, a high dielectric constant lanthanum oxide thin film (La2O3) was fabricated as a gate dielectric on GaAs pHEMTs to reduce the effect of the gate leakage caused by continuing the constant field-scaling trend of MOS technology. The chemical compositions and the crystalline structure at different annealing temperatures were observed by X-ray photoelectron spectroscopy (XPS) and x-ray diffraction (XRD) respectively, and the results reveal its significant thermal stability. By fabricating the capacitor, the dielectric constant of La2O3 with annealing at 400μ was calculated to be 21.6 which is higher than the sample without annealing. In addition, transistors with two different gate materials were successfully fabricated, Pt/La2O3/Ti/Au gate and the conventional Pt/Ti/Au gate. The DC results shown the oxide-device performed higher turn-on and breakdown voltage, exhibited better RF characteristic, and the gate leakage current was at least one order lower than the conventional device. Therefore, La2O3 is a potential candidate high-k material as the gate dielectric which can enhance the performance while scaling down the device dimension and overcome the thermal effect applied for high power applications.
UR - http://www.scopus.com/inward/record.url?scp=63249117706&partnerID=8YFLogxK
U2 - 10.1109/EDSSC.2008.4760647
DO - 10.1109/EDSSC.2008.4760647
M3 - 会议稿件
AN - SCOPUS:63249117706
SN - 9781424425402
T3 - 2008 IEEE International Conference on Electron Devices and Solid-State Circuits, EDSSC
BT - 2008 IEEE International Conference on Electron Devices and Solid-State Circuits, EDSSC
T2 - 2008 IEEE International Conference on Electron Devices and Solid-State Circuits, EDSSC
Y2 - 8 December 2008 through 10 December 2008
ER -