Methods of forming diffusion breaks on integrated circuit products comprised of finfet devices and the resulting products

Patent metadata

Field	Value
Publication number	US-2016163604-A1
Application number	US-201514674924-A
Country	US
Kind code	A1
Filing date	Mar 31, 2015
Priority date	Dec 5, 2014
Publication date	Jun 9, 2016
Grant date	—

Abstract

One illustrative method disclosed herein includes forming first sacrificial gate structures above a fin for two active gates and a dummy gate, removing the first sacrificial gate structure for the dummy gate so as to define a cavity that exposes the fin while leaving the first sacrificial gate structures for the two active gates intact, etching through the cavity to form a trench in the fin under the cavity, forming a second sacrificial gate structure for the dummy gate, removing the first sacrificial gate structures for the two active gates and the second sacrificial gate structure for the dummy gate so as to define a replacement gate cavity for the two active gates and the dummy gate, and forming a replacement gate structure in each of the replacement gate cavities, wherein the replacement gate structure for the dummy gate extends into the trench in the fin.

First claim

What is claimed:

1 . A method of forming a diffusion break between two active gates positioned above a fin formed in a semiconductor substrate, comprising:
forming first sacrificial gate structures above said fin for said two active gates and a dummy gate positioned between said two active gates; performing at least one process operation to remove said first sacrificial gate structure for said dummy gate so as to define a cavity that exposes said fin while leaving said first sacrificial gate structures for said two active gates intact; performing at least one etching process through said cavity to form a trench in said fin under said cavity; forming a second sacrificial gate structure in said trench and said cavity for said dummy gate; removing said first sacrificial gate structures for said two active gates and said second sacrificial gate structure for said dummy gate so as to define a replacement gate cavity for said two active gates and said dummy gate, wherein said replacement gate cavity for said dummy gate includes said trench in said fin; and forming a replacement gate structure in each of said replacement gate cavities, wherein said replacement gate structure for said dummy gate extends into said trench in said fin.

2 . The method of claim 1 , wherein performing said at least one process operation to remove said first sacrificial gate structure for said dummy gate comprises:
selectively removing a gate cap layer positioned above said first sacrificial gate structure for said dummy gate while masking gate cap layers positioned above said first sacrificial gate structures for said active gates: and performing at least one etching process to remove said first sacrificial gate structure for said dummy gate so as to define said cavity while said gate cap layers remain positioned above said first sacrificial gate structures for said active gates.

3 . The method of claim 1 , wherein, prior to forming said second sacrificial gate structure for said dummy gate, the method further comprises forming a liner layer comprised of an insulating material in said trench and in said cavity, and wherein said second sacrificial gate structure is formed on said liner layer.

4 . The method of claim 3 , wherein said liner layer is comprised of silicon nitride, a low-k nitride or silicon dioxide.

5 . The method of claim 1 , wherein said first sacrificial gate structures are comprised of one of polysilicon or amorphous silicon.

6 . The method of claim 1 , wherein said second sacrificial gate structure for said dummy gate is comprised of one of amorphous silicon or polysilicon.

7 . The method of claim 1 , wherein said replacement gate structures are comprised of a high-k gate insulation layer and at least one layer of metal.

8 . The method of claim 1 , wherein said replacement gate structures for said active gates comprise a gate insulation layer that is formed on the surface of said fin, and said gate insulation layer for said replacement gate structure for said dummy gate is formed on a liner layer comprised of an insulating material that is positioned in said trench and said cavity.

9 . The method of claim 1 , wherein said first sacrificial gate structure for said dummy gate is positioned immediately adjacent said first sacrificial gate structures for each of said active gates without any other first sacrificial gate structures being positioned therebetween.

10 . The method of claim 1 , wherein one of said active gates is for a first cell of circuits, the other of said active gates is for a second cell of circuits that is separate from said first cell, and said dummy gate is positioned at a boundary between said first and second cells.

11 . A method of forming a diffusion break between two active gates positioned above a fin formed in a semiconductor substrate, comprising:
forming first sacrificial gate structures above said fin for said two active gates and a dummy gate positioned between said two active gates; forming a patterned masking layer above said substrate, said patterned masking layer covering areas above said first sacrificial gate structures for said two active gates but having an opening that exposes an area above said first sacrificial gate structure for said dummy gate; performing at least one first etching process through said patterned masking layer to remove a gate cap layer positioned above said first sacrificial gate structure for said dummy gate while gate cap layers positioned above said first sacrificial gate structures for said active gates remain covered by said patterned masking layer; removing said patterned masking layer; performing at least one second etching process to remove said first sacrificial gate structure for said dummy gate so as to define a cavity that exposes said fin while leaving said first sacrificial gate structures for said two active gates intact; performing at least one third etching process through said cavity to form a trench in said fin under said cavity; forming a second sacrificial gate structure in said trench and said cavity for said dummy gate; removing said first sacrificial gate structures for said two active gates and said second sacrificial gate structure for said dummy gate so as to define a replacement gate cavity for said two active gates and said dummy gate, wherein said replacement gate cavity for said dummy gate includes said trench in said fin; and forming a replacement gate structure in each of said replacement gate cavities, wherein said replacement gate structure for said dummy gate extends into said trench in said fin.

12 . The method of claim 11 , wherein, prior to forming said second sacrificial gate structure for said dummy gate, the method further comprises forming a liner layer comprised of an insulating material in said trench and in said cavity, and wherein said second sacrificial gate structure is formed on said liner layer.

13 . The method of claim 12 , wherein said liner layer is comprised of silicon nitride, a low-k nitride or silicon dioxide.

14 . The method of claim 11 , wherein said replacement gate structures for said active gates comprise a gate insulation layer that is formed on the surface of said fin, and said gate insulation layer for said replacement gate structure for said dummy gate is formed on a liner layer that is positioned in said trench and said cavity.

15 . A method of forming a diffusion break between two active gates positioned above a fin formed in a semiconductor substrate, comprising:
forming first sacrificial gate structures above said fin for said two active gates and a dummy gate positioned between said two active gates; performing at least one process operation to remove said first sacrificial gate structure for said dummy gate so as to define a cavity that exposes said fin while leaving said first sacrificial gate structures for said two active gates intact; performing at least one etching process through said cavity to form a trench in said fin under said cavity; filling substantially all of said trench and said cavity for said dummy gate with an insulating material; removing said first sacrificial gate structures for said two active gates while leaving said insulating material in said trench and said cavity for said dummy gate intact so as to define a replacement gate cavity for each of said two active gates; and forming a replacement gate structure in each of said replacement gate cavities for said two active gates, wherein said insulating material in said trench and said cavity for said dummy gate remains intact.

16 . The method of claim 15 , where

Assignees

• Globalfoundries Inc

Inventors

• Xie Ruilong
• Sung Min Gyu
• Kim Ryan Ryoung-Han
• Lim Kwan-Yong
• Park Chanro

Classifications

• H10D86/215

  comprising FinFETs · CPC title

• H10D86/011

  comprising FinFETs · CPC title

• H10D84/853

  comprising FinFETs · CPC title

• H10D84/0193 Primary

  the components including FinFETs · CPC title

• H10D84/0181

  Manufacturing their gate insulating layers · CPC title