Title :
Work function controlled metal gate electrode on ultrathin gate insulators
Author :
Nakajima, K. ; Akasaka, Y. ; Kaneko, M. ; Tamaoki, M. ; Yamada, Y. ; Shimizu, T. ; Ozawa, Y. ; Suguro, K.
Author_Institution :
Microelectron. Eng. Lab., Toshiba Corp., Yokohama, Japan
Abstract :
We investigated MOS characteristics of metal gate electrodes on ultrathin gate oxide. Gate leakage currents of sputtered TiN and WN/sub x/ electrodes were found to be much higher than that of CVD TiN electrodes due to metal penetration during sputtering. Moreover, the deviation of crystal orientation of the TiN was found to affect the flat band voltage. The CVD TiN film was found to be formed with highly preferred orientation and to show very stable MOS characteristics, even on 2 nm gate oxide.
Keywords :
CMOS integrated circuits; CVD coatings; MOS capacitors; crystal orientation; electrodes; integrated circuit interconnections; integrated circuit metallisation; integrated circuit testing; leakage currents; sputtered coatings; texture; titanium compounds; tungsten compounds; work function; 2 nm; CMOS devices; CVD TiN electrodes; CVD TiN film; MOS capacitors; MOS characteristics; TiN-SiO/sub 2/-Si; WN-SiO/sub 2/-Si; crystal orientation; flat band voltage; gate leakage currents; gate oxide; metal gate electrodes; metal penetration; preferred orientation; sputtered TiN electrodes; sputtered WN/sub x/ electrodes; stable MOS characteristics; ultrathin gate insulators; ultrathin gate oxide; work function controlled metal gate electrode; Electrodes; Heating; Insulation; Leakage current; Metal-insulator structures; Microelectronics; Paramagnetic resonance; Sputtering; Tin; Tungsten;
Conference_Titel :
VLSI Technology, 1999. Digest of Technical Papers. 1999 Symposium on
Conference_Location :
Kyoto, Japan
Print_ISBN :
4-930813-93-X
DOI :
10.1109/VLSIT.1999.799357
