Methods of forming self-aligned contact structures on semiconductor devices and the resulting devices

Patent metadata

Field	Value
Publication number	US-2016163585-A1
Application number	US-201514674460-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 method disclosed includes, among other things, forming a structure comprised of an island of a first insulating material positioned between the gate structures above the source/drain region and under a masking layer feature of a patterned masking layer, forming a liner layer that contacts the island of insulating material and the masking layer feature, selectively removing the masking layer feature to thereby form an initial opening that is defined by the liner layer, performing at least one isotropic etching process through the initial opening to remove the island of first insulating material and thereby define a contact opening that exposes the source/drain region, and forming a conductive contact structure in the contact opening that is conductively coupled to the source/drain region.

First claim

What is claimed:

1 . A method of forming a self-aligned contact to a source/drain region of a transistor device positioned between two adjacent gate structures formed above a semiconductor substrate, the method comprising:
forming a structure comprised of an island of a first insulating material positioned between said gate structures above said source/drain region and under a masking layer feature of a patterned masking layer; forming a liner layer that contacts said island of said first insulating material and said masking layer feature; selectively removing said masking layer feature relative to said gate structures to thereby form an initial opening that is defined by said liner layer, said initial opening exposing said island of said first insulating material; performing at least one isotropic etching process through said initial opening to remove said island of said first insulating material and thereby define a contact opening that exposes said source/drain region; and forming a conductive contact structure in said contact opening that is conductively coupled to said source/drain region.

2 . The method of claim 1 , wherein said liner layer contacts all side surfaces of said masking layer feature and two side surfaces of said island of said first insulating material.

3 . The method of claim 1 , wherein, after forming said liner layer and prior to removing said masking layer feature, the method further comprises:
forming a second layer of insulating material that has an upper surface that is substantially planar with an upper surface of said masking layer feature; recessing said second layer of insulating material such that it has a recessed upper surface that is positioned below said upper surface of said masking layer feature; and forming a protective cap layer on said recessed upper surface of said second layer of insulating material, said protective cap layer contacting said liner layer.

4 . The method of claim 1 , wherein said first insulating material is comprised of silicon dioxide, said liner layer is comprised of silicon nitride, said patterned masking layer is comprised of amorphous silicon and said gate structures are each comprised of a silicon nitride gate cap layer and silicon nitride sidewall spacers.

5 . The method of claim 1 , wherein forming said conductive contact structure in said contact opening comprises:
forming at least one conductive material in said contact opening such that said contact opening is over-filled; performing a recess etching process on said at least one conductive material such that, after said recess etching process is performed, said conductive contact structure is formed in said contact opening and it has an upper surface that is positioned at a height level that is below an upper surface of a gate cap layer of said gate structures; forming a second layer of insulating material in said initial opening and above said conductive contact structure, said second layer of insulating material contacting said liner layer; and forming a contact in said second layer of insulating material that is conductively coupled to said upper surface of said conductive contact structure.

6 . The method of claim 1 , wherein forming said conductive contact structure in said contact opening comprises:
forming at least one conductive material in said contact opening such that said contact opening is over-filled and said at least one conductive material contacts said liner layer; performing at least one planarization process on at least said at least one conductive material so as to remove all materials positioned above a gate cap layer of each of said gate structures and thereby define said conductive contact structure in said contact opening; forming a second layer of insulating material above said gate structures and above said conductive contact structure; and forming a contact in said second layer of insulating material that is conductively coupled to an upper surface of said conductive contact structure.

7 . The method of claim 1 , wherein forming said conductive contact structure in said contact opening comprises:
forming at least one conductive material in said contact opening such that said contact opening is over-filled and said at least one conductive material contacts said liner layer; and performing a planarization process on said at least one conductive material.

8 . The method of claim 1 , wherein each of said gate structures comprises a gate insulation layer, a gate electrode, a gate cap layer and sidewall spacers.

9 . A method of forming self-aligned contacts to a plurality of source/drain regions of a transistor device, said transistor device comprising a gate structure that is positioned between two additional gate structures formed above a semiconductor substrate, the method comprising:
forming a first layer of insulating material between said gate structure and said additional gate structures above said source/drain regions; forming a patterned masking layer comprising a masking layer feature that covers portions of said first layer of insulating material above said source/drain regions and a portion of said gate structure, while leaving other portions of said first layer of insulating material exposed; performing a first etching process through said patterned masking layer to remove the exposed portions of said first layer of insulating material leaving islands of said first insulating material positioned above each of said source/drain regions and under said masking layer feature; forming a liner layer that contacts said islands of said first insulating material and all side surfaces of said masking layer feature; removing said masking layer feature to define an initial opening that is defined by said liner layer, said initial opening exposing said islands of first insulating material; performing at least one isotropic etching process through said initial opening to remove said islands of insulating material and thereby define a plurality of contact openings that expose said source/drain regions; and forming a conductive contact structure in each of said plurality of contact openings, wherein each of said conductive contact structures is conductively coupled to one of said source/drain regions.

10 . The method of claim 9 , wherein said additional gate structures are active-edge gate structures.

11 . The method of claim 9 , wherein, after forming said liner layer and prior to removing said masking layer feature, the method further comprises:
forming a second layer of insulating material that has an upper surface that is substantially planar with an upper surface of said masking layer feature; recessing said second layer of insulating material such that it has a recessed upper surface that is positioned below said upper surface of said masking layer feature; and forming a protective cap layer on said recessed upper surface of said second layer of insulating material, said protective cap layer contacting said liner layer.

12 . The method of claim 9 , wherein forming said conductive contact structure in each of said plurality of contact openings comprises:
forming at least one conductive material in said contact openings such that said contact openings are over-filled; performing a recess etching process on said at least one conductive material such that, after said recess etching process is performed, a conductive contact structure is formed in each of said contact openings and they each have an upper surface that is positioned at a height level that is below an upper surface of a gate cap layer of said gate structure; forming a third layer of insulating material in said initial

Assignees

• Globalfoundries Inc

Inventors

• Xie Ruilong
• Park Chanro
• Sung Min Gyu
• Kim Hoon
• Labonte Andre

Classifications

• H10W20/0696

  by using sacrificial placeholders, e.g. using sacrificial plugs · CPC title

• H10P14/40

  of conductive or resistive materials · CPC title

• H10W20/0698

  Local interconnections · CPC title

• H10W20/081

  by forming openings in the dielectric parts · CPC title

• H10W20/071

  of dielectric parts thereof · CPC title