Vertical field effect transistor including extension and stressors
AssigneeInternational Business Machines Corporation
InventorsKarthik Balakrishnan, Kangguo Cheng, Pouya Hashemi, Alexander Reznicek
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Abstract
A vertical field effect transistor (FET) includes a first source/drain region formed on an upper surface of a semiconductor substrate, and a semiconductor channel material that extends vertically from the first source/drain region to a second source/drain region. A metal gate structure encapsulating the semiconductor channel material. The vertical FET further includes a stressor region that contacts the semiconductor channel material and the first source/drain region. The combination of the semiconductor channel material and the stressor region defines a total length of a strained channel region of the vertical field effect transistor.
Claims15
A method of inducing strain on a channel region of a vertical transistor, the method comprising:
- forming a channel region that extends from a first source/drain region to a second source/drain region;
- encapsulating a first portion of the channel region with a first encapsulating structure and a second portion of the channel region with a second encapsulating structure;
- removing the second encapsulating structure while maintaining the first encapsulating structure to expose the second portion of the channel region;
- and
- replacing the second portion of the channel region with a stressor region that induces a strain on the first portion of the channel region.
A method of inducing a strain on a channel region of a vertical field effect transistor (FET), the method comprising:
- removing an encapsulating structure to form a void that exposes a first portion of the channel region, the channel region having a first lattice constant;
- selectively removing the first portion of the channel region while preserving a second portion of the channel region, the second portion having a first channel end connected to a first source/drain region and a second channel end exposed to the void;
- and
- forming a stressor region having a first stressor end formed against the second channel and a second stressor end formed against a second source/drain region, the stressor region having a second lattice constant different from the first lattice constant so as to induce a strain on the preserved second portion of the channel region.
Dependencies are inferred from the claim text.