Title :
Thermally robust TaTbxN metal gate electrode for n-MOSFETs applications
Author :
Ren, C. ; Yu, H.Y. ; Wang, X.P. ; Ma, H.H.H. ; Chan, Daniel S H ; Li, M.-F. ; Yeo, Yee-Chia ; Tung, C.H. ; Balasubramanian, N. ; Huan, A.C.H. ; Pan, J.S. ; Kwong, D.L.
Author_Institution :
Dept. of Electr. & Comput. Eng., Nat. Univ. of Singapore, Singapore
Abstract :
In this letter, we study Terbium (Tb)-incorporated TaN (TaTbxN) as a thermally robust N-type metal gate electrode for the first time. The work function of the Ta0.94Tb0.06Ny metal gate is determined to be ∼4.23 eV after rapid thermal anneal at 1000°C for 30 s, and can be further tuned by varying the Tb concentration. Moreover, the TaTbxN-SiO2 gate stack exhibits excellent thermal stability up to 1000°C with no degradation to the equivalent oxide thickness, gate leakage, and time-dependent dielectric breakdown (TDDB) characteristics. These results suggest that Tb-incorporated TaN (TaTbxN) could be a promising metal gate candidate for n-MOSFET in a dual-metal gate Si CMOS process.
Keywords :
MOSFET; electrodes; silicon compounds; tantalum compounds; terbium compounds; thermal stability; work function; 1000 C; 30 s; TaTbN-SiO2; TaTbaN-SiO2 gate stack; dual-metal gate Si CMOS process; equivalent oxide thickness; gate leakage; n-MOSFET applications; rapid thermal annealing; terbium-incorporated TaN; thermal stability; thermally robust metal gate electrode; time-dependent dielectric breakdown; work function; CMOS process; Dielectric breakdown; Electrodes; Gate leakage; MOSFET circuits; Rapid thermal annealing; Rapid thermal processing; Robustness; Thermal degradation; Thermal stability;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2004.841469
