Title :
Fully silicided NiSi gate on La2O3 MOSFETs
Author :
Lin, C.Y. ; Ma, M.W. ; Chin, Albert ; Yeo, Y.C. ; Zhu, Chunxiang ; Li, M.-F. ; Kwong, Dim-Lee
Author_Institution :
Dept. of Electron. Eng., Nat. Chiao Tung Univ., Hsinchu, Taiwan
fDate :
5/1/2003 12:00:00 AM
Abstract :
We have fabricated the fully silicided NiSi on La/sub 2/O/sub 3/ for n- and p-MOSFETs. For 900/spl deg/C fully silicided CoSi/sub 2/ on La/sub 2/O/sub 3/ gate dielectric with 1.5 nm EOT, the gate dielectric has large leakage current by possible excess Co diffusion at high silicidation temperature. In sharp contrast, very low gate leakage current density of 2/spl times/10/sup -4/ A/cm/sup 2/ at 1 V is measured for 400/spl deg/C formed fully silicided NiSi and comparable with Al gate. The extracted work function of NiSi was 4.42 eV, and the corresponding threshold voltages are 0.12 and -0.70 V for respective n- and p-MOSFETs. Electron and hole mobilities of 156 and 44 cm/sup 2//V-s are obtained for respective n- and p-MOSFETs, which are comparable with the HfO/sub 2/ MOSFETs without using H/sub 2/ annealing.
Keywords :
MOSFET; cobalt compounds; electron mobility; hole mobility; lanthanum compounds; leakage currents; nickel compounds; semiconductor device metallisation; work function; 400 degC; 900 degC; CoSi/sub 2/-La/sub 2/O/sub 3/; MOSFET; NiSi-La/sub 2/O/sub 3/; electron mobility; equivalent oxide thickness; fully silicided metal gate; gate dielectric; hole mobility; leakage current; threshold voltage; work function; Charge carrier processes; Current measurement; Density measurement; Dielectric measurements; Electron mobility; Leakage current; MOSFET circuits; Silicidation; Temperature; Threshold voltage;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2003.812569
