The effect of fluorine in an advanced CMOS process with triple (1.6/2.2/5.2 nm) nitrided gate oxide

Fluorine is introduced into the PFET and NFET of a triple-oxide (1.6/2.2/5.2 nm) 90 nm nitrided-oxide CMOS technology. While the effects on the PFET gate oxide are relatively subtle, the NFET is very significantly affected. The effective thickness of the oxide increases by 0.5 nm, much of the nitrogen is removed, and the structural integrity of the film is compromised. Electrical data, SIMS, TEM, and HRTEM analysis are used to characterize the films.