Methods for fabricating strained gate-all-around semiconductor devices by fin oxidation using an undercut etch-stop layer

• US 9,484,272 B2
• Filed: 04/30/2014
• Issued: 11/01/2016
• Est. Priority Date: 09/27/2012
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Cappellani, Annalisa, Pethe, Abhijit Jayant, Ghani, Tahir, Gomez, Harry
• Primary Examiner(s): Armand, Marc
• Assistant Examiner(s): Boulghassoul, Younes
• Application Number:
  US14/266,643
• Publication Number:
  US 20150318219A1
• Time in Patent Office: 916 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: H01L 21/30604 Chemical etching
• CPC Class Codes: H01L 21/762 Dielectric regions , e.g. EPIC dielectric isolation, LOCOS; Trench refilling techniques, SOI technology, use of channel stoppers
• CPC Class Codes: H01L 21/845 including field-effect transistors with a horizontal current flow in a vertical sidewall of a semiconductor body, e.g. FinFET, MuGFET
• CPC Class Codes: H01L 29/0649 Dielectric regions, e.g. SiO2 regions, air gaps
• CPC Class Codes: H01L 29/0673 oriented parallel to a substrate
• CPC Class Codes: H01L 29/0847 of field-effect transistors with insulated gate H01L29/0653 takes precedence; with a passive supplementary region between source or drain and substrate related to punch-through, capacity or isolation phenomena H01L29/1079; with LDD or DDD structure H01L29/7833; for thin film transistors H01L29/78618
• CPC Class Codes: H01L 29/1079 with insulated gate
• CPC Class Codes: H01L 29/401 Multistep manufacturing processes
• CPC Class Codes: H01L 29/41725 Source or drain electrodes for field effect devices with monocrystalline semiconductor on source/drain region H01L29/0843
• CPC Class Codes: H01L 29/42356 Disposition, e.g. buried gate electrode H01L29/42324 and H01L29/4234 take precedence
• CPC Class Codes: H01L 29/42392 fully surrounding the channel, e.g. gate-all-around
• CPC Class Codes: H01L 29/66439 with a one- or zero-dimensional channel, e.g. quantum wire FET, in-plane gate transistor [IPG], single electron transistor [SET], striped channel transistor, Coulomb blockade transistor with an active layer made of a group 13/15 material H01L29/66469
• CPC Class Codes: H01L 29/66545 using a dummy, i.e. replacement gate in a process wherein at least a part of the final gate is self aligned to the dummy gate
• CPC Class Codes: H01L 29/775 with one dimensional charge carrier gas channel, e.g. quantum wire FET
• CPC Class Codes: H01L 29/7848 the means being located in the source/drain region, e.g. SiGe source and drain
• CPC Class Codes: H01L 29/785 having a channel with a horizontal current flow in a vertical sidewall of a semiconductor body, e.g. FinFET, MuGFET
• CPC Class Codes: H01L 29/78696 characterised by the structure of the channel, e.g. multichannel, transverse or longitudinal shape, length or width, doping structure, or the overlap or alignment between the channel and the gate, the source or the drain, or the contacting structure of the channel H01L29/78612 takes precedence; transistors having a drain offset region or a lightly doped drain [LDD] H01L29/78621

Abstract

Strained gate-all-around semiconductor devices formed on globally or locally isolated substrates are described. For example, a semiconductor device includes a semiconductor substrate. An insulating structure is disposed above the semiconductor substrate. A three-dimensional channel region is disposed above the insulating structure. Source and drain regions are disposed on either side of the three-dimensional channel region and on an epitaxial seed layer. The epitaxial seed layer is composed of a semiconductor material different from the three-dimensional channel region and disposed on the insulating structure. A gate electrode stack surrounds the three-dimensional channel region with a portion disposed on the insulating structure and laterally adjacent to the epitaxial seed layer.

Claims

1. A method of fabricating a semiconductor device, the method comprising:

forming a three-dimensional semiconductor structure on an epitaxial seed layer disposed above a semiconductor substrate, the epitaxial seed layer comprising a semiconductor material different from the three-dimensional semiconductor structure;

etching the three-dimensional semiconductor structure to provide a three-dimensional channel region and to expose portions of the epitaxial seed layer on either side of the three-dimensional channel region;

forming source and drain regions on either side of the three-dimensional channel region and on the epitaxial seed layer;

insulating the three-dimensional channel region and the source and drain regions from the semiconductor substrate by forming an insulating structure comprising one or more isolation pedestals, the insulating structure continuous with the semiconductor substrate; and

, subsequently,

removing a portion of the epitaxial seed layer;

forming a gate electrode stack at least partially surrounding the three-dimensional channel region; and

forming a pair of conducting contacts, one contact at least partially surrounding the source region, and another contact at least partially surrounding the drain region, wherein removing the portion of the epitaxial seed layer comprises removing a portion between the source and drain regions and the semiconductor substrate, and wherein the one contact surrounds the source region and the other contact surrounds the drain region.

2. The method of claim 1, wherein forming the gate electrode stack comprises using a replacement gate process.

3. The method of claim 1, wherein removing the portion of the epitaxial seed layer further comprises removing a portion between the three-dimensional channel region and the semiconductor substrate, and wherein the gate electrode stack surrounds the three-dimensional channel region.

4. A method of fabricating a semiconductor device, the method comprising:

forming a three-dimensional semiconductor structure on an epitaxial seed layer disposed above a semiconductor substrate, the epitaxial seed layer comprising a semiconductor material different from the three-dimensional semiconductor structure;

etching the three-dimensional semiconductor structure to provide a three-dimensional channel region and to expose portions of the epitaxial seed layer on either side of the three-dimensional channel region;

forming source and drain regions on either side of the three-dimensional channel region and on the epitaxial seed layer;

insulating the three-dimensional channel region and the source and drain regions from the semiconductor substrate by forming an insulating structure comprising one or more isolation pedestals, the insulating structure continuous with the semiconductor substrate;

removing a portion of the epitaxial seed layer;

forming a gate electrode stack at least partially surrounding the three-dimensional channel region; and

forming a pair of conducting contacts, one contact at least partially surrounding the source region, and another contact at least partially surrounding the drain region, wherein removing the portion of the epitaxial seed layer comprises removing a portion between the source and drain regions and the semiconductor substrate, and wherein the one contact surrounds the source region and the other contact surrounds the drain region.

5. The method of claim 4, wherein forming the gate electrode stack comprises using a replacement gate process.

6. The method of claim 4, wherein removing the portion of the epitaxial seed layer further comprises removing a portion between the three-dimensional channel region and the semiconductor substrate, and wherein the gate electrode stack surrounds the three-dimensional channel region.