US4589196A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Contacts for VLSI devices using direct-reacted silicide
Assignee: Texas Instruments Inc
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Filing: 1984-10-11
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Granted: 1986-05-20
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Expires: 2004-10-11
Abstract
Abstract Metal contacts and interconnections for semiconductor integrated circuits are formed by a process using direct-reacted silicide to increase step or sidewall coverage. First a thin layer of titanium or other refractory metal is deposited, extending into a contact hole, then polysilicon is deposited and a preferential etch removes all of the polysilicon except on the vertical sides of steps or apertures. A second thin layer of titanium is deposited, then a heat treatment forms silicide to create conductive sidewalls or a plug. Metal contacts then engage the direct-reacted silicide rather than relying upon step coverage.
Inventors
- 👤 Dirk N. Anderson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:51
CPC Classifications
H; H10; H10D; H10D64/00; H10D64/01; H10D64/011; H10D64/0111; H10D64/0112; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/064; H10W20/066; Y; Y10; Y10S; Y10S148/00; Y10S148/019; Y10S148/02; Y10S148/147
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
178 words
A method of making contact to a face of a semiconductor body through an aperature in an insulating layer on said face, comprising the steps of: (a) depositing a thin layer of conductive material on said face to cover the semiconductor body within said aperture and also to cover the insulating layer and the sidewalls of the aperture, (b) depositing a layer of semiconductor material over said conductive material and etching said layer of semiconductor material from said face but leaving the layer in place on the sidewalls, (c) depositing another thin layer of conductive material on said face to extend continuously over the insulator and over the layer of semiconductor material and down the sidewall into the aperature, (d) reacting the thin layer of conductive material with the semiconductor material to form a silicide/semiconductor material structure, (e) removing unwanted residue of said thin and said another thin layers of conductive material from said insulating layer, (f) depositing a metal layer over said insulator to make contact to the reacted conductive material and semiconductor material at said aperture.
Claim 2
Independent Claim
178 words
A method of making contact to a face of a semiconductor body through an aperature in an insulating layer on said face, comprising the steps of: (a) depositing a thin layer of conductive material on said face to cover the semiconductor body within said aperture and also to cover the insulating layer and the sidewalls of the aperture, (b) depositing a layer of semiconductor material over said conductive material and etching said layer of semiconductor material from said face but leaving the layer in place on the sidewalls, (c) depositing another thin layer of conductive material on said face to extend continuously over the insulator and over the layer of semiconductor material and down the sidewall into the aperature, (d) reacting the thin layer of conductive material with the semiconductor material to form a silicide/semiconductor material structure, (e) removing unwanted residue of said thin and said another thin layers of conductive material from said insulating layer, (f) depositing a metal layer over said insulator to make contact to the reacted conductive material and semiconductor material at said aperture.
Claim 3
Dependent Claim
20 words
A method according to claim 1 wherein said conductive material is a refractory metal and said semiconductor material is silicon.
Claim 4
Dependent Claim
22 words
A method according to claim 2 wherein said layer of semiconductor material is polycrystalline silicon, and said insulating layer is silicon oxide.
Claim 5
Dependent Claim
12 words
A method according to claim 4 wherein said refractory metal is titanium.
Claim 6
Dependent Claim
26 words
A method according to claim 4 wherein said another thin layer extends into said aperture to make direct contact to the semiconductor material at said face.
Claim 7
Independent Claim
167 words
A method of making a metal connection at a face of a semiconductor body, said connection extending over a step in an insulating layer on said face, comprising the steps of: (a) depositing a first layer of conductive material on said face to cover the semiconductor body and to cover the insulating layer and the sidewall of the step, (b) depositing a layer of semiconductor material of said first layer of conductive material and selectively removing the layer of semiconductor material over said insulating layer but leaving the layer on said sidewall, (c) depositing a second layer of said conductive material on said face to extend continuously across the step over the layer of semiconductor material, (d) reacting the conductive material with the semiconductive material to form a silicide/semiconductor material structure, (e) removing unwanted residue of said first and second layers of conductive material over the insulating layer, (f) depositing a conductor on said face to engage the reacted conductive material and semiconductor material at said step.
Claim 8
Independent Claim
167 words
A method of making a metal connection at a face of a semiconductor body, said connection extending over a step in an insulating layer on said face, comprising the steps of: (a) depositing a first layer of conductive material on said face to cover the semiconductor body and to cover the insulating layer and the sidewall of the step, (b) depositing a layer of semiconductor material of said first layer of conductive material and selectively removing the layer of semiconductor material over said insulating layer but leaving the layer on said sidewall, (c) depositing a second layer of said conductive material on said face to extend continuously across the step over the layer of semiconductor material, (d) reacting the conductive material with the semiconductive material to form a silicide/semiconductor material structure, (e) removing unwanted residue of said first and second layers of conductive material over the insulating layer, (f) depositing a conductor on said face to engage the reacted conductive material and semiconductor material at said step.
Claim 9
Dependent Claim
20 words
A method according to claim 6 wherein said conductive material is a refractory metal and said semiconductor material is silicon.
Claim 10
Dependent Claim
22 words
A method according to claim 7 wherein said layer of semiconductor material is polycrystalline silicon, and said insulating layer is silicon oxide.
Claim 11
Dependent Claim
12 words
A method according to claim 8 wherein said refractory metal is titanium.
Claim 12
Dependent Claim
26 words
A method according to claim 6 wherein said another thin layer extends into said aperture to make direct contact to the semiconductor material at said face.
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1989-05-19 | 1989-11-18 | 1990-05-20 | $2000.00 | Window Closed / Lapsed |
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