Title :
RTP formed oxynitride via direct nitridation in N2
Author :
Khoueir, A. ; Lu, Z.H. ; Ng, W.T. ; Tay, S.P. ; Lai, P.T.
Author_Institution :
Dept. of Metall. & Mater. Sci., Toronto Univ., Ont., Canada
Abstract :
The continuous scale down of devices to smaller feature sizes in order to maximize integration density demands a decrease in the thickness of the gate dielectric in advanced complementary metal-oxide-semiconductor (CMOS) devices. Once the thickness of the SiO 2 is reduced below about 3 nm, the regime of direct tunneling becomes predominant resulting in large leakage current. When the thickness of SiO2 is reduced below 2 nm, the reliability of the gate oxide becomes a major problem where alternative gate dielectrics must be considered. In this work, using a novel method via direct nitridation in N2, two different processing approaches were undergone to produce rapid thermal processing (RTP) nitrided oxides or oxynitrides. One approach is the direct nitridation of the Si surface with N2 gas at an elevated temperature (>1150°C) to form Si3N4 followed by O2 oxidation, while the second method simply involves O2 oxidation of the Si wafer to form SiO2 followed by N2 nitridation. The aim of this work is to electrically characterise the ultrathin films and prove its viability as a SiO2 substitute for future CMOS device generations
Keywords :
CMOS integrated circuits; nitridation; rapid thermal processing; 1150 C; 3 nm; CMOS device; N2; SiO2; direct nitridation; direct tunneling; gate dielectric thickness reduction; integration density; large leakage current; rapid thermal processing; reliability; Capacitance-voltage characteristics; Capacitors; Current measurement; Dielectric substrates; Leakage current; Nitrogen; Optical films; Oxidation; Stress measurement; Voltage;
Conference_Titel :
Electron Devices Meeting, 2000. Proceedings. 2000 IEEE Hong Kong
Conference_Location :
Hong Kong
Print_ISBN :
0-7803-6304-3
DOI :
10.1109/HKEDM.2000.904226