Title :
Improved Stability of High-Performance ZnO/ZnMgO Hetero-MISFETs
Author :
Sasa, Shigehiko ; Hayafuji, Takeo ; Kawasaki, Motoki ; Koike, Kazuto ; Yano, Mitsuaki ; Inoue, Masataka
Author_Institution :
Nanomater. Microdevices Res. Center, Osaka
fDate :
7/1/2007 12:00:00 AM
Abstract :
Improved performance and stability was demonstrated for ZnO/ZnMgO hetero-MISFETs. The MIS gate structures that were formed using either a 50-nm-thick Al2O3 or HfO2 gate dielectric layer were examined by observation of the transfer characteristic hysteresis. A significantly reduced hysteresis of less than 0.1 V was obtained for HfO2 as compared to that for the Al2O3 gate dielectric. By reducing the access resistance, the 1-mum gate devices showed improved transconductance values, as high as 54 mS/mm for Al2O3 and 71 mS/mm for HfO2, which are the highest values ever reported for ZnO-based FETs.
Keywords :
II-VI semiconductors; MISFET; alumina; dielectric materials; hafnium compounds; wide band gap semiconductors; zinc compounds; Al2O3; Al2O3 - Binary; HfO2; HfO2 - Binary; MIS gate structures; ZnMgO; ZnMgO hetero-MISFET; ZnO; ZnO hetero-MISFET; gate dielectric layer; size 1 mum; size 50 nm; transfer characteristic hysteresis; Dielectrics; Fabrication; Hafnium oxide; Hysteresis; Plasma devices; Plasma temperature; Stability; Thin film transistors; Transconductance; Zinc oxide; $hbox{Al}_{2}hbox{O}_{3}$; $hbox{HfO}_{2}$; MISFET; ZnO/ZnMgO; gate dielectric; molecular beam epitaxy; thin-film transistor (TFT);
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2007.899448
