Gate all around vacuum channel transistor
AssigneeSTMicroelectronics S.r.l.
InventorJohn H. Zhang
Life of this patent
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Abstract
A vacuum channel transistor having a vertical gate-all-around (GAA) architecture provides high performance for high-frequency applications, and features a small footprint compared with existing planar devices. The GAA vacuum channel transistor features stacked, tapered source and drain regions that are formed by notching a doped silicon pillar using a lateral oxidation process. A temporary support structure is provided for the pillar during formation of the vacuum channel. Performance of the GAA vacuum channel transistor can be tuned by replacing air in the channel with other gases such as helium, neon, or argon. A threshold voltage of the GAA vacuum channel transistor can be adjusted by altering dopant concentrations of the silicon pillar from which the source and drain regions are formed.
Claims20
A method, comprising:
- forming a first semiconductor pillar structure over a substrate, the first semiconductor oriented in a first direction and having a first tapered end pointing away from the substrate;
- forming a second semiconductor pillar structure oriented in the first direction and spaced apart from the first semiconductor pillar structure, the second semiconductor structure having a second tapered end pointing toward the substrate, the second tapered end being separated from the first taped end by a gap region;
- and
- forming a gate structure adjacent to the gap region in a second direction transverse to the first direction.
A method, comprising:
- forming a vertical stack over a substrate, the vertical stack including:
- a first portion having a first tapered end;
- and
- a second portion over the first portion and having a second tapered end that faces the first tapered end;
- and
- forming a gate structure laterally adjacent to the first tapered end and the second tapered end.
A method, comprising:
- forming a first source or drain structure over a substrate, the first source or drain structure having a first point;
- forming a second source or drain structure over the first source or drain source structure, the second source or drain structure having a second point spaced apart from the first point by a first gap;
- forming an insulator layer laterally surrounding the second source or drain structure and vertically overlapping the first source or drain source structure;
- and
- forming a gate surrounding the first gap.
Dependencies are inferred from the claim text.