US5500382A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Self-aligned contact process
Assignee: STMicroelectronics lnc USA
•
Filing: 1994-08-19
•
Granted: 1996-03-19
•
Expires: 2014-08-19
Abstract
Abstract A method for forming a self-aligned contact utilizes a thin insulating layer formed on the upper surface of a conductive layer. A barrier layer is deposited over the insulating layer, and gate electrodes are then defined. Sidewall spacers are formed along the vertical sidewalls of the gate electrodes. During formation of the sidewall spacers the barrier layer protects the gate electrodes. A second insulating layer is then deposited and a via is opened to the substrate. A contact can now be created by depositing conductive material into the via.
Inventors
- 👤 Che-Chia Wei
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 00:05
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/069
Claims Analysis
Total Claims: 41
Claim 1
Independent Claim
92 words
A method for forming a self-aligned contact for a device, comprising the steps of: forming a gate electrode having a first insulating layer and a barrier layer on the upper surface thereof, wherein the barrier layer is comprised of a material having a high etch selectivity to a material in the first insulating layer; forming sidewall spacers alongside the gate electrode, wherein the barrier layer protects the gate electrode during formation of the sidewall spacers; depositing a second insulating layer over the device; and opening a via through the second insulating layer.
Claim 2
Independent Claim
92 words
A method for forming a self-aligned contact for a device, comprising the steps of: forming a gate electrode having a first insulating layer and a barrier layer on the upper surface thereof, wherein the barrier layer is comprised of a material having a high etch selectivity to a material in the first insulating layer; forming sidewall spacers alongside the gate electrode, wherein the barrier layer protects the gate electrode during formation of the sidewall spacers; depositing a second insulating layer over the device; and opening a via through the second insulating layer.
Claim 3
Dependent Claim
23 words
The method of claim 1, wherein a portion of the barrier layer is converted into an insulating layer after formation of the via.
Claim 4
Dependent Claim
28 words
The method of claim 2, wherein said step of converting a portion of the barrier layer into an insulating layer comprises oxidizing a portion of the barrier layer.
Claim 5
Dependent Claim
17 words
The method of claim 1, wherein said barrier layer is removed after formation of the sidewall spacers.
Claim 6
Dependent Claim
25 words
The method of claim 4, wherein said step of removing the barrier layer after formation of the sidewall spacers comprises isotropically etching said barrier layer.
Claim 7
Dependent Claim
31 words
The method of claim 1, wherein a portion of the barrier layer is removed after opening the via, wherein the barrier layer protects the gate electrode during formation of the via.
Claim 8
Dependent Claim
33 words
The method of claim 6, wherein said step of removing a portion of the barrier layer after opening the via comprises isotropically etching said layer, wherein a part of the barrier layer remains.
Claim 9
Dependent Claim
19 words
The method of claim 7, wherein a portion of the remaining barrier layer is converted into an insulating area.
Claim 10
Dependent Claim
29 words
The method of claim 8, wherein said step of converting a portion of the remaining barrier layer into an insulating area comprises oxidizing a portion of the barrier layer.
Claim 11
Dependent Claim
75 words
The method of claim 1, wherein said step of forming a gate electrode comprises the steps of: forming a third insulating layer over a portion of a semiconductor substrate; depositing a conductive layer over the device; depositing the first insulating layer over the conductive layer; depositing the barrier layer over the first insulating layer; and removing a portion of the barrier layer, the first insulating layer, and the conductive layer to define the gate electrode.
Claim 12
Dependent Claim
25 words
The method of claim 10, wherein said step of forming a third insulating layer comprises growing thermal oxide on a portion of the semiconductor substrate.
Claim 13
Dependent Claim
12 words
The method of claim 10, wherein said conductive layer comprises polycrystalline silicon.
Claim 14
Dependent Claim
12 words
The method of claim 10, wherein said first insulating layer comprises oxide.
Claim 15
Dependent Claim
12 words
The method of claim 10, wherein said barrier layer comprises titanium nitride.
Claim 16
Dependent Claim
50 words
The method of claim 10, wherein said step of removing a portion of the barrier layer, the first insulating layer, and the conductive layer comprises the steps of: depositing and patterning a masking layer over the device; anisotropically etching the device to open the via; and removing the masking layer.
Claim 17
Dependent Claim
31 words
The method of claim 1, wherein said step of forming sidewall spacers comprises the steps of: depositing a conformal insulating layer over the device; and anisotropically etching said conformal insulating layer.
Claim 18
Dependent Claim
12 words
The method of claim 16, wherein said conformal insulating layer comprises oxide.
Claim 19
Dependent Claim
12 words
The method of claim 1, wherein said second insulating layer comprises oxide.
Claim 20
Dependent Claim
57 words
The method of claim 1, wherein the device is formed on a semiconductor substrate wherein said step of opening a via comprises the steps of: depositing and patterning a masking layer over the device; anisotropically etching the device so as to expose a portion of the semiconductor substrate to open the via; and removing the masking layer.
Claim 21
Dependent Claim
15 words
The method of claim 1, wherein a conductive contact is formed after opening the via.
Claim 22
Dependent Claim
37 words
The method of claim 20, wherein said conductive contact is made between the gate electrode and a second gate electrode adjacent to the gate electrode, wherein the contact is self-aligned with respect to the two gate electrodes.
Claim 23
Independent Claim
138 words
A method for forming a self-aligned contact for a device, comprising the steps of: forming a first insulating layer over a portion of a semiconductor substrate; depositing a conductive layer over the device; depositing a second insulating layer over the conductive layer wherein the barrier layer is comprised of a material having a high etch selectivity to a material in the second insulating layer; depositing a barrier layer over the second insulating layer; removing a portion of the barrier layer, second insulating layer and conductive layer to define a gate electrode; depositing a third insulating layer over the device; forming sidewall spacers from the third insulating layer, wherein the barrier layer protects the gate electrode during formation of the sidewall spacers; depositing a fourth insulating layer over the device; and opening a via through the fourth insulating layer.
Claim 24
Independent Claim
138 words
A method for forming a self-aligned contact for a device, comprising the steps of: forming a first insulating layer over a portion of a semiconductor substrate; depositing a conductive layer over the device; depositing a second insulating layer over the conductive layer wherein the barrier layer is comprised of a material having a high etch selectivity to a material in the second insulating layer; depositing a barrier layer over the second insulating layer; removing a portion of the barrier layer, second insulating layer and conductive layer to define a gate electrode; depositing a third insulating layer over the device; forming sidewall spacers from the third insulating layer, wherein the barrier layer protects the gate electrode during formation of the sidewall spacers; depositing a fourth insulating layer over the device; and opening a via through the fourth insulating layer.
Claim 25
Dependent Claim
25 words
The method of claim 22, wherein said step of forming a first insulating layer comprises growing thermal oxide on a portion of the semiconductor substrate.
Claim 26
Dependent Claim
12 words
The method of claim 22, wherein said conductive layer comprises polycrystalline silicon.
Claim 27
Dependent Claim
12 words
The method of claim 22, wherein said second insulating layer comprises oxide.
Claim 28
Dependent Claim
12 words
The method of claim 22, wherein said barrier layer comprises titanium nitride.
Claim 29
Dependent Claim
63 words
The method of claim 22, wherein said step of removing a portion of the barrier layer, second insulating layer and conductive layer comprises the steps of: depositing and patterning a masking layer over the device; anisotropically etching the device to remove a portion of the barrier layer, second insulating layer and conductive layer to define the gate electrode; and removing the masking layer.
Claim 30
Dependent Claim
12 words
The method of claim 22, wherein said third insulating layer comprises oxide.
Claim 31
Dependent Claim
19 words
The method of claim 22, wherein said step of forming sidewall spacers comprises anisotropically etching the third insulating layer.
Claim 32
Dependent Claim
12 words
The method of claim 22, wherein said fourth insulating layer comprises oxide.
Claim 33
Dependent Claim
46 words
The method of claim 22, wherein said step of opening a via comprises the steps of: depositing and patterning a masking layer over the device; anisotropically etching the device to expose a portion of the semiconductor substrate to open the via; and removing the masking layer.
Claim 34
Dependent Claim
17 words
The method of claim 22, wherein said barrier layer is removed after formation of the sidewall spacers.
Claim 35
Dependent Claim
18 words
The method of claim 32, wherein said step of removing the barrier layer comprises isotropically etching the layer.
Claim 36
Dependent Claim
31 words
The method of claim 22, wherein a portion of said barrier layer is removed after opening the via, wherein the barrier layer protects the gate electrode during formation of the via.
Claim 37
Dependent Claim
31 words
The method of claim 34, wherein said step of removing a portion of the barrier layer after opening the via comprises isotropically etching said layer wherein a remaining barrier layer remains.
Claim 38
Dependent Claim
19 words
The method of claim 35, wherein a portion of the remaining barrier layer is converted into an insulating area.
Claim 39
Dependent Claim
28 words
The method of claim 36, wherein said step of converting a portion of the barrier layer into an insulating area comprises oxidizing a portion of the barrier layer.
Claim 40
Dependent Claim
15 words
The method of claim 22, wherein a conductive contact is formed after opening the via.
Claim 41
Dependent Claim
37 words
The method of claim 38, wherein said conductive contact is made between the gate electrode and a second gate electrode adjacent to the gate electrode, wherein the contact is self-aligned with respect to the two gate electrodes.
References Cited (Backward Citations)
US4743564A
Cited
US4855798A
Cited
US5075762A
Cited
US4922311A
Cited
US5019527A
Cited
US5043790A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-03-19 | 1999-09-18 | 2000-03-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-03-19 | 2003-09-18 | 2004-03-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-03-19 | 2007-09-18 | 2008-03-19 | $7700.00 | Window Closed / Lapsed |