Scully, Scott, Murphy & Presser, P.C.
Asymmetric FET
After forming a first-side epitaxial semiconductor region and a second-side epitaxial semiconductor region on recessed surfaces of a semiconductor portion that are not covered by a gate structure, at least one dielectric layer is formed to cover the first-side and the second-side epitaxial semiconductor regions and the gate structure. A second-side contact opening is formed within the at least one dielectric layer to expose an entirety of the second-side epitaxial semiconductor region. The exposed second-side epitaxial semiconductor region can be replaced by a new second-side epitaxial semiconductor region having a composition different from the first-side epitaxial semiconductor region or can be doped by additional dopants, thus creating an asymmetric first-side epitaxial semiconductor region and a second-side epitaxial semiconductor region. Each of the first-side epitaxial semiconductor region and the second-side epitaxial semiconducting region can function as either a source or a drain for a transistor.
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inventional inventional additional additional inventional inventional inventional inventional inventional inventional inventional additional inventional inventional inventional inventional inventional inventional inventional inventional inventional inventional inventional inventional
Joseph Juntao Chengwen Kangguo Geng
Ervin Li Pei Cheng Wang