# US 2014/0151766 A1 · FinFET DEVICE WITH DUAL-STRAINED CHANNELS AND METHOD FOR MANUFACTURING THEREOF

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

- Number: US 2014/0151766 A1
- Document ID: US20140151766A1
- Status: Published application
- Kind: A1
- Application number: 14/086,486
- Filed: 2013-11-21
- Published: 2014-06-05
- Earliest claimed: 2012-12-05
- Assignees: Imec
- Applicants: Imec
- Inventors: Geert Eneman; Benjamin Vincent; Voon Yew Thean
- Web page: https://patentgrep.com/patent/US20140151766A1

## CPC

- H10D 84/834: {comprising FinFETs}
- H10D 30/751: {having composition variations in the channel regions}
- H10D 30/791: {Arrangements for exerting mechanical stress on the crystal lattice of the channel regions}
- H10D 30/798: {being provided in or under the channel regions}
- H10D 62/115: {Dielectric isolations, e.g. air gaps}
- 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 62/8325: {Silicon carbide}
- H10D 84/0193: {the components including FinFETs}
- H10D 84/038: {using silicon technology, e.g. SiGe}
- H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES

## Abstract

A FinFET device and a method for manufacturing a FinFET device is provided. An example device may comprise a substrate including at least two fin structures. Each of the at least two fin structures may be in contact with a source and drain region and each of the at least two fin structures may include a strain relaxed buffer (SRB) overlying and in contact with the substrate and an upper layer overlying and in contact with the SRB. The composition of the upper layer and the SRB may be selected such that the upper layer of a first fin structure is subjected to a first mobility enhancing strain in the as-grown state, the first mobility enhancing strain being applied in a longitudinal direction from the source region to the drain region and where at least an upper part of the upper layer of a second fin structure is strain-relaxed.

## Claims

### Claim 1

Method for manufacturing a dual channel FinFET device having at least one channel subjected to a mobility enhancement strain, the method comprising:
providing a substrate comprising at least two fin structures separated by an isolation region, each of the fin structures in physical contact with a source region and a drain region,
wherein each of the at least two fin structures comprises an upper layer suitable to form a n-type or p-type channel and a strained relaxed buffer (SRB) underlying and in contact with said upper layer, and overlying and in contact with the substrate,
wherein a composition of the upper layer and the SRB is selected such that the upper layer of a first fin structure is subjected to a first mobility enhancing strain in an as-grown state, the first mobility enhancing strain being applied in a longitudinal direction from the source region to the drain region,
performing an ion implantation in at least a part of the upper layer of a second fin structure, thereby forming an amorphous layer, then
performing a re-crystallization by laser anneal of the amorphous layer, thereby forming a strain-relaxed upper layer of the second fin structure.

### Claim 2 (depends on 1)

The method according to claim 1, wherein the first mobility enhancing strain is a compressive strain.

### Claim 3 (depends on 2)

The method according to claim 2, wherein SRB comprises Si1-xGex and the upper layer comprises Si1-yGey, wherein y>x, 0<x<1 and 0<y≦1.

### Claim 4 (depends on 2)

The method according to claim 2, wherein SRB comprises Si1-wCw and the upper layer comprises Si1-yGey, wherein 0<w≦0.1 and 0≦y≦0.25.

### Claim 5 (depends on 1)

The method according to claim 1, wherein the first mobility enhancing strain is a tensile strain.

### Claim 6 (depends on 5)

The method according to claim 5, wherein the SRB comprises Si1-xGex and the upper layer comprises Si1-yGey, wherein y<x, 0<x<1 and 0≦y<1.

### Claim 7 (depends on 5)

The method according to claim 5, wherein SRB comprises Ge1-tSnt and the upper layer comprises Si1-yGey, wherein 0<t≦0.1 and 0.75≦y≦1.

### Claim 8

Method for manufacturing a dual channel FinFET device having each channel subjected to a mobility enhancement strain, the method comprising
providing a substrate comprising at least two fin structures separated by an isolation region, each of the fin structures in physical contact with a source region and a drain region, wherein each of the at least two fin structures comprises
a strained relaxed buffer (SRB) wherein the SRB comprises at least two layers, a SRB1 overlying and in contact with the substrate and a SRB2 overlying and in contact with SRB1 and
a first upper layer overlying and in contact with the SRB2, said first upper layer being suitable to form a n-type or p-type channel, wherein a composition of the first upper layer and the SRB2 is selected such that the first upper layer of a first fin structure is subjected to a first mobility enhancing strain in an as-grown state, the first mobility enhancing strain being applied in a longitudinal direction from the source region to the drain region
performing an ion implantation in the first upper layer and at least an upper part of SRB2 of the second fin structure, thereby forming an amorphous buffer layer, then
performing a re-crystallization by laser anneal of the amorphous buffer layer, thereby forming a strain-relaxed buffer layer of the second fin structure,
forming a recess in the second fin structure by removing part of the strain-relaxed buffer layer, thereby exposing a remaining strain-relaxed buffer layer, then
filling the recess in the second fin structure by epitaxial growth of a upper layer on the remaining strain-relaxed buffer layer, wherein a composition of the upper layer is chosen such that the second upper layer is subjected to a second mobility enhancing strain in the as-grown state, the second mobility enhancing strain being applied in a longitudinal direction from the source region to the drain region.

### Claim 9 (depends on 8)

Method according to claim 8, wherein the first upper layer and SRB2 have a same composition, the method further comprising:
simultaneously with forming a recess in the second fin structure forming a recess in the first fin structure thereby consuming the first upper layer and/or part of the SRB2 of the first fin structure and exposing a remaining SRB2 and
simultaneously with filling the recess in the second fin structure, filling the recess in the first fin structure by epitaxial growth of an upper layer on the remaining SRB2, wherein a composition of the upper layer is chosen such that the upper layer is subjected in the as-grown state to a second mobility enhancing strain in the second fin structure and to a first mobility enhancing strain in the first fin structure, wherein both the first and the second mobility enhancing strain being applied in a longitudinal direction from the source region to the drain region.

### Claim 10 (depends on 8)

The method according to claim 8, wherein the second mobility enhancing strain is a compressive strain and the first mobility enhancing strain is a tensile strain.

### Claim 11 (depends on 10)

The method according to claim 10, wherein the SRB1 comprises Si1-xGex, SRB2 comprises Si1-yGey and wherein each of the upper layer and the first upper layer comprises Si1-zGez, wherein y<z<x, 0<x≦1, 0<y<1, 0<z<1.

### Claim 12

The method according to 10, wherein the SRB1 comprises Si1-xGex, SRB2 comprises Si1-wCw and wherein each of the upper layer and the first upper layer comprises Si1-yGey, wherein y<x, 0<x<1, 0≦y<1, and 0<w≦0.1.

### Claim 13 (depends on 10)

The method according to claim 10, wherein the SRB1 comprises Ge1-tSnt, SRB2 comprises Si1-xGex and wherein each of the upper layer and the first upper layer comprises Si1-yGey, wherein y>x, 0<x<1, 0<y≦1, and 0<t≦0.1.

### Claim 14

A dual channel FinFET device having at least one channel subjected to a mobility enhancement strain, the device comprising:
a substrate comprising at least two fin structures separated by an isolation region, wherein each of the at least two fin structures is in physical contact with a source region and a drain region and wherein each of the at least two fin structures comprises a strain relaxed buffer (SRB) overlying and in contact with the substrate and an upper layer overlying and in contact with the SRB, said upper layer being suitable to form a n-type or p-type channel which is protruding from the substrate
wherein the composition of the upper layer and the SRB is selected such that the upper layer of a first fin structure is subjected to a first mobility enhancing strain in the as-grown state, the first mobility enhancing strain being applied in a longitudinal direction from the source region to the drain region and
wherein at least an upper part of the upper layer of a second fin structure is strain-relaxed.

### Claim 15

A dual channel FinFET device having each channel subjected to a mobility enhancement strain, the device comprising:
a substrate comprising at least two fin structures separated by an isolation region, wherein each of the at least two fin structures is in physical contact with a source region and a drain region and
wherein each of the at least two fin structures comprises a strain relaxed buffer (SRB) overlying and in contact with the substrate, wherein the SRB comprises at least two layers, a SRB1 overlying and in contact with the substrate and a SRB2 overlying and in contact with SRB1,
wherein a first fin structure further comprises an first upper layer overlying and in contact with the SRB2, said first upper layer is protruding from the substrate and is suitable to form a n-type or p-type channel, wherein the composition of the first upper layer and the SRB2 is selected such that the upper layer of a first fin structure is subjected to a first mobility enhancing strain in the as-grown state, the first mobility enhancing strain being applied in a longitudinal direction from the source region to the drain region,
wherein an upper part of the SRB2 of a second fin structure is strain-relaxed and the second fin structure further comprises a upper layer overlying and in contact with said strain-relaxed upper part of SRB2, the upper layer protruding from the substrate and being suitable to form a n-type or p-type channel
wherein the composition of the upper layer is chosen such that the upper layer is subjected to a second mobility enhancing strain in the as-grown state, the second mobility enhancing strain being applied in a longitudinal direction from the source region to the drain region.