Low Temperature Microwave Anneal in FinFET Fabrication

Abstract

Low temperature anneal solutions are attractive for 7 nm CMOS transistor fabrication and beyond. This desire is necessitated by the introduction of new materials, novel integration flows and alternate device architectures that are incompatible with high temperature anneal solutions. Recently, microwave anneal has emerged as a potential approach for low temperature processing. We have demonstrated an alternate low temperature anneal run path using microwave anneal for Titanium silicidation. The best in class microwave annealed split had matched contact resistivity and slightly improved device performance relative to the mSec annealed control wafer. HRTEM of both anneal processes revealed comparable silicidation. Moreover, we demonstrated densification of FCVD grown oxide using low temperature microwave anneal. The wet etch rate ratio (WERR) achieved was comparable to that obtained from high temperature steam oxidation process. This low temperature process could be highly useful for fabrication of devices that use materials that suffer from unwanted diffusion, oxidization, and defects resulting from high temperature anneals. Keywords—microwave, anneal, activation, trench, contacts, silicide, TiSi, FinFET, processes, materials. Figure 1