Epitaxy Source/Drain Regions of FinFETs and Method Forming Same
AssigneeTaiwan Semiconductor Manufacturing Company, Ltd.
InventorsTung-Husan Hung, Guan-Jie Shen, Pin-Cheng Hsu
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Abstract
A method includes forming isolation regions extending into a semiconductor substrate, and recessing the isolation regions, so that portions of semiconductor strips between the isolation regions protrude higher than the isolation regions to form semiconductor fins. The method further includes recessing the semiconductor fins to form recesses, epitaxially growing a first semiconductor material from the recesses, etching the first semiconductor material, and epitaxially growing a second semiconductor material from the first semiconductor material that has been etched back.
Claims20
A method comprising:
- forming a first isolation region and a second isolation region, with a semiconductor fin between the first isolation region and the second isolation region, wherein the first isolation region extends deeper into a semiconductor substrate than the second isolation region;
- recessing the semiconductor fin to form a recess between the first isolation region and the second isolation region;
- performing a first epitaxy to grow a semiconductor region from the recess;
- etching the semiconductor region;
- and
- performing a second epitaxy to enlarge the semiconductor region.
A method comprising:
- forming a first isolation region extending into a semiconductor substrate;
- forming a second isolation region extending into the semiconductor substrate;
- forming a first semiconductor fin and a second semiconductor fin, with the first semiconductor fin being between the first isolation region and the second isolation region, and the second isolation region being between the first semiconductor fin and the second semiconductor fin, wherein the first isolation region extends into a semiconductor substrate deeper than the second isolation region;
- recessing the first semiconductor fin and the second semiconductor fin to form a first recess and a second recess, respectively;
- and
- growing a semiconductor region from the first recess and the second recess, wherein an air gap is sealed underneath the semiconductor region, and the air gap overlaps the second isolation region.
A method comprising:
- forming a first isolation region;
- forming a second isolation region, wherein a semiconductor strip is between the first isolation region and the second isolation region, and the first isolation region and the second isolation region are formed of different materials;
- recessing the first isolation region and the second isolation region, so that a portion of the semiconductor strip protrudes higher than the first isolation region and the second isolation region to form a semiconductor fin;
- forming a gate stack over a first portion of the semiconductor fin;
- etching a second portion of the semiconductor fin to form a recess;
- growing a first semiconductor material from the recess;
- etching the first semiconductor material;
- and
- growing a second semiconductor material on the first semiconductor material.
Dependencies are inferred from the claim text.