Field effect transistor with a hybrid gate spacer including a low-k dielectric material

Abstract

A FET including a hybrid gate spacer separating a gate electrode from at least one of a source, a drain, or source/drain contact metallization. The hybrid spacer may include a low-k dielectric material for a reduction in parasitic capacitance. The hybrid spacer may further include one or more other dielectric materials of greater relative permittivity that may protect one or more surfaces of the low-k dielectric material from damage by subsequent transistor fabrication operations. The hybrid spacer may include a low-k dielectric material separating a lower portion of a gate electrode sidewall from the source/drain terminal, and a dielectric spacer cap separating to an upper portion of the gate electrode sidewall from the source/drain terminal. The hybrid spacer may have a lower total capacitance than conventional spacers while still remaining robust to downstream fabrication processes. Other embodiments may be described and/or claimed.