# US 10,374,091 B2 · Silicon germanium fin immune to epitaxy defect

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 10,374,091 B2
- Document ID: US10374091B2
- Status: Granted
- Kind: B2
- Application number: 16/112,841
- Filed: 2018-08-27
- Published: 2019-01-03
- Granted: 2019-08-06
- Earliest claimed: 2015-12-28
- Assignees: International Business Machines Corporation
- Applicants: International Business Machines Corporation
- Inventors: Kangguo Cheng; Juntao Li; Xin Miao
- Web page: https://patentgrep.com/patent/US10374091B2

## CPC

- H10D 30/62: Fin field-effect transistors [FinFET]
- H10D 30/024: {of fin field-effect transistors [FinFET]}
- H10D 30/0241: {doping of vertical sidewalls, e.g. using tilted or multi-angled implants}
- H10D 30/6211: {having fin-shaped semiconductor bodies integral with the bulk semiconductor substrates}
- H10D 30/797: {being in source or drain regions, e.g. SiGe source or drain}
- H10D 62/151: {of IGFETs (of IGFETs having LDD or DDD structure H10D30/601; of thin film transistors H10D30/6713)}
- H10D 62/822: comprising only Group IV materials heterojunctions, e.g. Si/Ge heterojunctions
- H10D 62/832: being Group IV materials comprising two or more elements, e.g. SiGe
- H10D 64/017: {using dummy gates in processes wherein at least parts of the final gates are self-aligned to the dummy gates, i.e. replacement gate processes}
- H10D 64/021: {using multiple gate spacer layers, e.g. bilayered sidewall spacers}
- H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES

## Abstract

A method for forming a semiconductor structure includes forming at least one fin on a semiconductor substrate. The least one fin includes a semiconducting material. A gate is formed over and in contact with the at least one fin. A germanium comprising layer is formed over and in contact with the at least one fin. Germanium from the germanium comprising layer is diffused into the semiconducting material of the at least one fin.

## Claims

### Claim 1

A method of forming a semiconductor structure, the method comprising:
forming at least one fin on a semiconductor substrate, the least one fin comprising a semiconductor material;
forming a gate over and in contact with the at least one fin, wherein the gate is a dummy gate;
depositing a germanium comprising layer over and in contact with an exposed top surface of the at least one fin;
diffusing germanium from the germanium comprising layer into the semiconducting material of the at least one fin;
removing the gate after the germanium has been diffused; and
forming a gate stack over and in contact with the at least one fin after the gate has been removed.

### Claim 2 (depends on 1)

The method of claim 1, further comprising:
forming a spacer layer in contact with the dummy gate, wherein the gate stack is formed in contact with the spacer layer after the dummy gate has been removed.

### Claim 3 (depends on 1)

The method of claim 1, wherein forming the gate stack comprises:
forming a dielectric layer over and in contact with the at least one fin.

### Claim 4 (depends on 3)

The method of claim 3, wherein forming the gate stack further comprises:
after forming the gate dielectric layer, forming a gate conductor layer over and in contact with the gate dielectric layer.

### Claim 5 (depends on 1)

The method of claim 1, further comprising:
forming a spacer layer on sidewalls of the gate stack.

### Claim 6 (depends on 1)

The method of claim 1, further comprising:
after forming the gate stack, forming a source region and a drain region in contact with the at least one fin.

### Claim 7 (depends on 6)

The method of claim 6, further comprising:
forming a dielectric layer on and in contact with the source region and the drain region.

### Claim 8 (depends on 1)

The method of claim 1, further comprising:
forming a nitride layer on an in contact with the gate.

### Claim 9 (depends on 1)

The method of claim 1, wherein the germanium comprising layer is deposited prior to forming the source region and the drain region.

### Claim 10

A method of forming a semiconductor structure, the method comprising:
forming a plurality of fins on a semiconductor substrate, each fin of the plurality of fins comprising a semiconductor material;
forming a plurality of gates, wherein each gate of the plurality of gates is formed over a portion of each fin of the plurality of fins, wherein each of the plurality of gates is a dummy gate;
depositing a plurality of germanium comprising layers, wherein each germanium comprising layer of the plurality of germanium comprising layers is deposited over and in contact with an exposed top surface of one fin of the plurality of fins;
diffusing germanium from the plurality of germanium comprising layers into the semiconducting material of the plurality of fins;
removing the gate after the germanium has been diffused; and
forming a plurality gate stacks after each of the gates has been removed, wherein each gate stack of the plurality of gate stacks is formed over and in contact a portion of each fin of the plurality of fins.

### Claim 11 (depends on 10)

The method of claim 10, wherein forming each gate stack of the plurality of gate stacks comprises:
forming a dielectric layer over and in contact with the portion of the fin.

### Claim 12 (depends on 11)

The method of claim 11, wherein forming each gate stack of the plurality of gate stacks comprises:
after forming the gate dielectric layer, forming a gate conductor layer over and in contact with the gate dielectric layer.

### Claim 13 (depends on 10)

The method of claim 10, further comprising:
forming a spacer layer on sidewalls of each gate stack of the plurality of gate stacks.

### Claim 14 (depends on 10)

The method of claim 10, further comprising:
after forming the plurality of gate stacks, forming a source region and a drain region in contact with the plurality of fins.

### Claim 15 (depends on 14)

The method of claim 14, further comprising:
forming a dielectric layer on and in contact with the source region and the drain region.

### Claim 16 (depends on 14)

The method of claim 14, wherein the germanium comprising layer is deposited prior to forming the source region and the drain region.