Author :
Hsu, P.F. ; Hou, Y.T. ; Yen, F.Y. ; Chang, V.S. ; Lim, P.S. ; Hung, C.L. ; Yao, L.G. ; Jiang, J.C. ; Lin, H.J. ; Chiou, J.M. ; Yin, K.M. ; Lee, J.J. ; Hwang, R.L. ; Jin, Y. ; Chang, Steven Min ; Tao, H.J. ; Chen, S.C. ; Liang, M.S. ; Ma, T.P.
Abstract :
This paper reports the fabrication of MOSFETs with dual metal gate electrodes. Low threshold voltage (Vt) was achieved using TaC for nFETs and MoNx for pFETs. The transistors show excellent Ion-Ioff performance with well-controlled short channel effects. Benefited from a novel approach in base oxide formation, high mobility at ~90% of poly/SiO2 was achieved on thick HfO2 (30A). Improvement in current drivability by the incorporation of conventional cap stressor was also presented. The data demonstrates one of the best MOSFETs to date with dual metal gates on high-k dielectrics. It is further observed that high-k crystallization induces Vt non-uniformity in small devices. To our knowledge, the impact of crystallization to high- k manufacturability is addressed here for the first time
Keywords :
MOSFET; dielectric materials; hafnium compounds; molybdenum compounds; silicon compounds; tantalum compounds; CMOS application; HfO2; MoN; TaC; base oxide formation; conventional cap stressor; dual metal gate MOSFET; dual metal gate electrodes; high-k dielectric; Crystallization; Electrodes; Fabrication; Hafnium oxide; High K dielectric materials; High-K gate dielectrics; MOSFETs; Manufacturing; Threshold voltage; Transistors;
