Title :
MOS devices with high quality ultra thin CVD ZrO/sub 2/ gate dielectrics and self-aligned TaN and TaN/poly-Si gate electrodes
Author :
Lee, C.H. ; Kim, Y.H. ; Luan, H.F. ; Lee, S.J. ; Jeon, T.S. ; Bai, W.P. ; Kwong, D.L.
Author_Institution :
Dept. of Electr. & Comput. Eng., Texas Univ., Austin, TX, USA
Abstract :
In this paper, we have successfully fabricated and characterized self-aligned TaN and TaN/poly-Si gated n-MOSFETs with ultra thin (EOT=11 /spl Aring/) CVD ZrO/sub 2/ gate dielectrics. It is show that while both gate stacks show excellent leakage current and good thermal stability after a 900/spl deg/C, 30 s, N/sub 2/ anneal, the TaN/poly-Si ZrO/sub 2/ devices exhibit superior thermal stability even after 1000/spl deg/C, 30 s, N/sub 2/ anneal. In addition, the TaN/poly-Si devices show negligible frequency dependence of CV, charge trapping, and superior TDDB characteristics, compared to TaN devices. Well-behaved N-MOSFETs with both TaN and TaN/poly-Si gate electrodes are demonstrated.
Keywords :
MOSFET; chemical vapour deposition; dielectric thin films; electron traps; elemental semiconductors; hole traps; leakage currents; rapid thermal annealing; semiconductor device breakdown; semiconductor device metallisation; silicon; tantalum compounds; thermal stability; zirconium compounds; 1000 C; 11 angstrom; 30 s; 900 C; CV frequency dependence; MOS devices; N-MOSFETs; N/sub 2/; N/sub 2/ anneal; Si-TaN-ZrO/sub 2/; TDDB characteristics; TaN gate electrodes; TaN gated n-MOSFETs; TaN-ZrO/sub 2/; TaN/poly-Si ZrO/sub 2/ devices; TaN/poly-Si gate electrodes; TaN/poly-Si gated n-MOSFETs; charge trapping; gate stacks; leakage current; quality; self-aligned TaN gate electrodes; self-aligned TaN/poly-Si gate electrodes; thermal stability; ultra thin CVD ZrO/sub 2/ gate dielectrics; Dielectric devices; Doping; Electrodes; Leakage current; MOS devices; MOSFET circuits; Rapid thermal annealing; Rapid thermal processing; Thermal stability; Tin;
Conference_Titel :
VLSI Technology, 2001. Digest of Technical Papers. 2001 Symposium on
Conference_Location :
Kyoto, Japan
Print_ISBN :
4-89114-012-7
DOI :
10.1109/VLSIT.2001.934987
