Radical nitridation in multi-oxide process for 100 nm generation CMOS technology

Abstract

We propose a new multi-oxide technology, which drastically improves the ratio of the drive current to the gate leakage current for both high-performance (HP) transistors and low-power (LP) transistors on the same die. The key technology is radical nitridation (Watanabe et al, Appl. Phys. Lett. vol. 76, p. 2940, 2000; Togo et al, VLSI Tech. Symp., p. 116, 2000) followed by multi-oxide formation. In addition, it is easier to integrate with conventional CMOS processes compared with high-k dielectrics. Only one additional step reduces equivalent oxide thickness (EOT) of the LP transistor by 0.3 nm, thereby improving the drive current (I/sub on/). It also suppresses the gate leakage current (I/sub g/) for HP transistors by two orders of magnitude without an increase of EOT. Each oxide thickness of the multi-oxide is scalable to support various system-on-a-chip (SoC) applications.