Title :
Direct evidence of gate oxide thickness increase in tungsten polycide processes
Author :
Hsu, S.L. ; Liu, L.M. ; Lin, M.S. ; Chang, C.Y.
Author_Institution :
Taiwan Semicond. Manuf. Co., Hsin-Chu, Taiwan
Abstract :
The increase of the effective gate oxide thickness for W-polycide processes is studied. The samples with as-deposited and annealed W polycide were analyzed by secondary ion mass spectrometry, transmission electron microscopy (TEM), and high-frequency CV measurements. The TEM cross section shows that the gate oxide thicknesses are approximately 244 and approximately 285 AA for as-deposited and 1000 degrees C annealed samples, respectively. The TEM results agree with those from CV measurements. The TEM analyses provide direct physical evidence of an additional oxide thickness ( approximately 41 AA) during the W-polycide annealing.<>
Keywords :
annealing; metallisation; oxidation; tungsten compounds; TEM; W-polycide annealing; W-polycide processes; WSi/sub x/ process; direct physical evidence; gate oxide thickness increase; gate oxide thicknesses; high-frequency CV measurements; polysilicon W silicide; secondary ion mass spectrometry; silicides; transmission electron microscopy; CMOS integrated circuits; CMOS process; CMOS technology; Dielectric measurements; Manufacturing processes; Mass spectroscopy; Rapid thermal annealing; Thickness measurement; Transmission electron microscopy; Tungsten;
Journal_Title :
Electron Device Letters, IEEE
