US5070038A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of forming low-resistive contact to N+/P+ preohmic regions in very large scale integrated devices
Assignee: Samsung Electronics Co Ltd
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Filing: 1988-12-27
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Granted: 1991-12-03
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Expires: 2008-12-27
Abstract
Abstract A method of forming low-resistive contact to at least two preohmic regions formed in a silicon substrate having a thick insulating layer thereon, including the steps of depositing a polysilicon on the insulating layer, performing an anisotropic etch for opening the preohmic regions, sputter-depositing a titanium deposit, the deposited titanium having electrical disconnections on the vertical side-walls of the opening regions, siliciding the titanium deposit, and depositing a metal silicide deposit for preventing electrical disconnections. Another embodiment uses a sputter-deposited titanium silicide deposit instead of titanium silicide. Still another embodiment includes the step of forming holes by an anisotropic etch, depositing polysilicon in the holes and on the insulating layer, sputter-depositing an titanium deposit, forming an titanium silicide deposit, and depositing a metal silicide deposit.
Inventors
- 👤 Dae-Je Jin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 09:07
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/064; H10W20/066; H10D; H10D64/00; H10D64/01; H10D64/011; H10D64/0111; H10D64/0112; H10P; H10P14/00; H10P14/20; H10P14/22; H10P14/40; H10P14/412; H10P14/414; H10P14/416; H10W20/056; H10W20/40; H10W20/41; H10W20/44; H10W20/4403; H10W20/4437; H10W20/4441; H10W20/4451; Y; Y10; Y10S; Y10S148/00; Y10S148/019; Y10S148/026; Y10S148/147
Claims Analysis
Total Claims: 38
Claim 1
Independent Claim
112 words
A method of forming low-resistive contacts to at least two preohmic regions formed in a silicon substrate, comprising the steps of: forming an insulating layer on the face of the silicon substrate; depositing a polycrystalline silicon layer on the insulating layer; forming holes having features of vertical side-walls in the insulating layer and the polycrystalline silicon layer so that face portions of the preohmic regions are completely exposed; depositing titanium on the polycrystalline silicon layer and the exposed preohmic regions; forming a layer of titanium silicide so that the titanium reacts with the underlying silicon; and depositing a metal silicide on the titanium silicide layer and the side-walls of the insulating layer.
Claim 2
Independent Claim
112 words
A method of forming low-resistive contacts to at least two preohmic regions formed in a silicon substrate, comprising the steps of: forming an insulating layer on the face of the silicon substrate; depositing a polycrystalline silicon layer on the insulating layer; forming holes having features of vertical side-walls in the insulating layer and the polycrystalline silicon layer so that face portions of the preohmic regions are completely exposed; depositing titanium on the polycrystalline silicon layer and the exposed preohmic regions; forming a layer of titanium silicide so that the titanium reacts with the underlying silicon; and depositing a metal silicide on the titanium silicide layer and the side-walls of the insulating layer.
Claim 3
Dependent Claim
14 words
The method of claim 1, wherein the insulating layer is formed of silicon dioxide.
Claim 4
Dependent Claim
14 words
The method of claim 2, wherein the metal silicide is formed of tungsten silicide.
Claim 5
Dependent Claim
17 words
The method of claim 3, wherein the preohmic regions are formed of N+ or P+ preohmic regions.
Claim 6
Dependent Claim
30 words
The method of claim 3, wherein at least one of the preohmic regions is formed of a P+ preohmic region and remaining preohmic regions are formed of N+ preohmic regions.
Claim 7
Dependent Claim
39 words
The method of claim 5, wherein, in conjunction with the formation of the tungsten silicide layer, the concentration P-type impurities are introduced into the P+ preohmic region and high concentration N-type impurities are introduced into the N+ preohmic regions.
Claim 8
Dependent Claim
13 words
The method of claim 6, wherein the titanium is formed by sputter deposition.
Claim 9
Dependent Claim
15 words
The method of claim 7, wherein the tungsten silicide is deposited by chemical vapor deposition.
Claim 10
Independent Claim
86 words
A method of forming low-resistive contacts to at least two preohmic regions formed in a silicon substrate, comprising the steps of: forming an insulating layer on the face of the silicon substrate; forming holes having features of vertical side-walls in the insulating layer so that face portions of the preohmic regions are completely exposed; depositing a layer of titanium silicide on the insulating layer and the exposed preohmic regions; and depositing a metal silicide on the titanium silicide layer and the side-walls of the insulating layer.
Claim 11
Independent Claim
86 words
A method of forming low-resistive contacts to at least two preohmic regions formed in a silicon substrate, comprising the steps of: forming an insulating layer on the face of the silicon substrate; forming holes having features of vertical side-walls in the insulating layer so that face portions of the preohmic regions are completely exposed; depositing a layer of titanium silicide on the insulating layer and the exposed preohmic regions; and depositing a metal silicide on the titanium silicide layer and the side-walls of the insulating layer.
Claim 12
Dependent Claim
23 words
The method of claim 9, further comprising the step of depositing a polycrystalline silicon layer between the insulating layer and the titanium silicide.
Claim 13
Dependent Claim
14 words
The method of claim 10, wherein the insulating layer is formed of silicon dioxide.
Claim 14
Dependent Claim
14 words
The method of claim 11, wherein the metal silicide is formed of tungsten silicide.
Claim 15
Dependent Claim
30 words
The method of claim 12, wherein at least one of the preohmic regions is formed of a P+ preohmic region and remaining preohmic regions are formed of N+ preohmic regions.
Claim 16
Dependent Claim
39 words
The method of claim 13, wherein in conjunction with the formation of the tungsten silicide layer, high concentration P-type impurities are introduced into the P+ preohmic region and high concentration N-type impurities are introduced into the N+ preohmic regions.
Claim 17
Dependent Claim
14 words
The method of claim 14, wherein the titanium silicide is formed by sputter deposition.
Claim 18
Dependent Claim
17 words
The method of claim 15, wherein the titanium silicide is a titanium-silicon composition having ratio of 1:2.6.
Claim 19
Dependent Claim
13 words
The method of claim 15, wherein the titanium silicide is formed by sputtering.
Claim 20
Dependent Claim
17 words
The method of claim 11, wherein the preohmic regions are formed of N+ or P+ preohmic regions.
Claim 21
Independent Claim
112 words
A method of forming low-resistive contacts through holes in an insulating layer formed on the face of a silicon substrate to at least two preohmic regions exposed by said holes, said holes having substantially vertical side-walls in the insulating layer, comprising the steps of: depositing polycrystalline silicon on the insulating layer, the side-walls of the holes and the exposed preohmic region; depositing titanium on the face of the polycrystalline layer and the polycrystalline silicon above the exposed preohmic region; forming a layer of titanium silicide so that the titanium reacts with the underlying polycrystalline silicon; and depositing a metal silicide on the titanium silicide layer and the side-walls of the polycrystalline silicon.
Claim 22
Independent Claim
112 words
A method of forming low-resistive contacts through holes in an insulating layer formed on the face of a silicon substrate to at least two preohmic regions exposed by said holes, said holes having substantially vertical side-walls in the insulating layer, comprising the steps of: depositing polycrystalline silicon on the insulating layer, the side-walls of the holes and the exposed preohmic region; depositing titanium on the face of the polycrystalline layer and the polycrystalline silicon above the exposed preohmic region; forming a layer of titanium silicide so that the titanium reacts with the underlying polycrystalline silicon; and depositing a metal silicide on the titanium silicide layer and the side-walls of the polycrystalline silicon.
Claim 23
Dependent Claim
14 words
The method of claim 19, comprised of forming the insulating layer of silicon dioxide.
Claim 24
Dependent Claim
14 words
The method of claim 20, wherein the metal silicide is formed of tungsten silicide.
Claim 25
Dependent Claim
17 words
The method of claim 21, wherein the preohmic regions are formed of N+ or P+ preohmic regions.
Claim 26
Dependent Claim
29 words
The method of claim 21, wherein at least one of the preohmic regions is formed of a P+ region and remaining preohmic regions are formed of N+ preohmic regions.
Claim 27
Dependent Claim
39 words
The method of claim 23, wherein in conjunction with the formation of the tungsten silicide layer, high concentration P-type impurities are introduced into the P+ preohmic region and high concentration N-type impurities are introduced into the N+ preohmic regions.
Claim 28
Dependent Claim
13 words
The method of claim 24, wherein the titanium is formed by sputter deposition.
Claim 29
Dependent Claim
15 words
The method of claim 25, wherein the tungsten silicide is deposited by chemical vapor deposition.
Claim 30
Independent Claim
117 words
A method of forming low-resistive contracts to a preohmic region of a substrate, comprising: forming an electrically insulating layer on a face of the substrate bearing a preohmic region; forming a hole in the insulating layer to expose a portion of the face of the preohmic region in the substrate, with the hole having generally vertically disposed side-walls; concurrently forming a layer of titanium silicide on the insulating layer and a layer of titanium silicide on the exposed face portion of the preohmic region; and depositing a layer of metal silicide electrically connecting the titanium silicide layer formed on the insulating layer and the titanium silicide layer formed on the exposed face portion of the preohmic region.
Claim 31
Independent Claim
117 words
A method of forming low-resistive contracts to a preohmic region of a substrate, comprising: forming an electrically insulating layer on a face of the substrate bearing a preohmic region; forming a hole in the insulating layer to expose a portion of the face of the preohmic region in the substrate, with the hole having generally vertically disposed side-walls; concurrently forming a layer of titanium silicide on the insulating layer and a layer of titanium silicide on the exposed face portion of the preohmic region; and depositing a layer of metal silicide electrically connecting the titanium silicide layer formed on the insulating layer and the titanium silicide layer formed on the exposed face portion of the preohmic region.
Claim 32
Dependent Claim
62 words
The method of claim 27, further comprised of concurrently forming said layers of titanium silicide by: forming a polycrystalline silicon layer on the insulating layer and the exposed face portion of the preohmic region; forming a titanium layer on the polycrystalline silicon layer; and causing the titanium layer to react with the polycrystalline silicon layer to form said layer of titanium silicide.
Claim 33
Dependent Claim
59 words
The method of claim 27, further comprised of: forming a layer of polycrystalline silicon upon said insulating layer; forming said hole through said insulating layer and said polysilicon layer; and concurrently forming said layers of titanium silicide by sputtering from a silicon-rich titanium-silicide target, onto said polycrystalline silicon layer and onto said exposed face portion of the preohmic region.
Claim 34
Dependent Claim
34 words
The method of claim 29, further comprised of subjecting the preohmic region to ion implantation in conjunction with the step of electrically connecting the titanium silicide layers by depositing said layer of metal silicide.
Claim 35
Dependent Claim
62 words
The method of claim 27, further comprised of: forming a layer of polycrystalline silicon upon said insulating layer, upon the exposed face portion of the preohmic region, and upon the side-walls of the hole; forming a titanium layer on the polycrystalline silicon layer; and causing the titanium layer to react with the polycrystalline silicon layer to form said layer of titanium silicide.
Claim 36
Dependent Claim
34 words
The method of claim 31, further comprised of subjecting the preohmic region to ion implantation in conjunction with the step of electrically connecting the titanium silicide layers by depositing said layer of metal silicide.
Claim 37
Dependent Claim
34 words
The method of claim 27, further comprised of subjecting the preohmic region to ion implantation is conjunction with the step of electrically connecting the titanium silicide layers by depositing said layer of metal silicide.
Claim 38
Dependent Claim
34 words
The method of claim 28, further comprised of subjecting the preohmic region to ion implantation in conjunction with the step of electrically connecting the titanium silicide layers by depositing said layer of metal silicide.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-12-02 | 1995-06-03 | 1995-12-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-12-02 | 1999-06-03 | 1999-12-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-12-02 | 2003-06-03 | 2003-12-03 | $7700.00 | Window Closed / Lapsed |