Finfet and gate-all-around fet with selective high-k oxide deposition

Abstract

A semiconductor device structure is provided. The semiconductor device structure includes a fin structure formed over a semiconductor substrate and a gate structure formed across the fin structure. The semiconductor device structure also includes an isolation feature over a semiconductor substrate and below a portion of the gate structure and two spacer elements respectively formed over a first sidewall and a second sidewall of the gate structure. In addition, the first sidewall is opposite to the second sidewall and the two spacer elements have hydrophobic surfaces respectively facing the first sidewall and the second sidewall, and the gate structure includes a gate dielectric layer and a gate electrode layer separating the gate dielectric layer from the hydrophobic surfaces of the two spacer elements.