US6136664A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Filling of high aspect ratio trench isolation
Assignee: International Business Machines Corp
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Filing: 1997-08-07
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Granted: 2000-10-24
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Expires: 2017-08-07
Abstract
Abstract A method of forming a trench isolation on a semiconductor substrate comprising the steps of forming a trench in the substrate, partially filling the trench with a first layer of polysilicon, oxidizing the first layer of polysilicon, partially filling the trench with at least a second layer of polysilicon, and oxidizing the second layer of polysilicon. By utilizing the method of the present invention, formation of voids and defects in a trench isolation having a high aspect ratio can be prevented.
Inventors
- 👤 Laertis Economikos
- 👤 David Edward Kotecki
- 👤 Jack A. Mandelman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 02:08
CPC Classifications
H; H10; H10W; H10W10/00; H10W10/01; H10W10/011; H10W10/014; H10W10/0142; H10W10/10; H10W10/17
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
113 words
A method of forming a trench isolation on a semiconductor substrate, comprising the steps of: forming a trench in said substrate, the trench having side walls and a bottom; partially filling said trench with a first layer of silicon, so that the bottom of the trench is covered by said first layer of silicon; oxidizing said first layer of silicon, so that the bottom of the trench is covered by an oxide of silicon; partially filling said trench with at least a second layer of silicon; and oxidizing said second layer of silicon, wherein said trench is partially filled with said second layer of silicon after said first layer of silicon is oxidized.
Claim 2
Independent Claim
113 words
A method of forming a trench isolation on a semiconductor substrate, comprising the steps of: forming a trench in said substrate, the trench having side walls and a bottom; partially filling said trench with a first layer of silicon, so that the bottom of the trench is covered by said first layer of silicon; oxidizing said first layer of silicon, so that the bottom of the trench is covered by an oxide of silicon; partially filling said trench with at least a second layer of silicon; and oxidizing said second layer of silicon, wherein said trench is partially filled with said second layer of silicon after said first layer of silicon is oxidized.
Claim 3
Dependent Claim
30 words
The method, as recited in claim 1, further comprising the step of forming a layer of nitride in said trench prior to filling said trench with said layers of silicon.
Claim 4
Dependent Claim
66 words
The method, as recited in claim 1, further comprising the steps of: forming a layer of pad oxide on said substrate prior to forming said trench; forming a layer of silicon nitride on said layer of pad oxide; forming a patterned masking layer on said layer of silicon nitride; and etching said silicon nitride layer, said pad oxide layer, and said substrate to form said trench.
Claim 5
Dependent Claim
18 words
The method, as recited in claim 1, wherein said trench has a predetermined width and a predetermined depth.
Claim 6
Dependent Claim
20 words
The method, as recited in claim 4, wherein the ratio of said depth to said width is greater than two.
Claim 7
Dependent Claim
22 words
The method, as recited in claim 4, wherein said first layer of silicon is approximately one-third of said depth of said trench.
Claim 8
Dependent Claim
22 words
The method, as recited in claim 4, wherein said second layer of silicon is approximately one-third of said depth of said trench.
Claim 9
Dependent Claim
18 words
The method, as recited in claim 1, wherein said first layer of silicon comprises amorphous or polycrystalline silicon.
Claim 10
Dependent Claim
18 words
The method, as recited in claim 1, wherein said second layer of silicon comprises amorphous or polycrystalline silicon.
Claim 11
Independent Claim
115 words
A method of manufacturing a semiconductor device, comprising the steps of: providing a silicon substrate; forming a trench in said substrate, so that the trench has side walls and a bottom; partially filling said trench with a first layer of silicon, so that the bottom of the trench is covered by said first layer of silicon; oxidizing said first layer of silicon, so that the bottom of the trench is covered by an oxide of silicon; partially filling said trench with at least a second layer of silicon; and oxidizing said second layer of silicon, wherein said trench is partially filled with said second layer of silicon after said first layer of silicon is oxidized.
Claim 12
Independent Claim
115 words
A method of manufacturing a semiconductor device, comprising the steps of: providing a silicon substrate; forming a trench in said substrate, so that the trench has side walls and a bottom; partially filling said trench with a first layer of silicon, so that the bottom of the trench is covered by said first layer of silicon; oxidizing said first layer of silicon, so that the bottom of the trench is covered by an oxide of silicon; partially filling said trench with at least a second layer of silicon; and oxidizing said second layer of silicon, wherein said trench is partially filled with said second layer of silicon after said first layer of silicon is oxidized.
Claim 13
Dependent Claim
30 words
The method, as recited in claim 10, further comprising the step of forming a layer of nitride in said trench prior to filling said trench with said layers of silicon.
Claim 14
Dependent Claim
66 words
The method, as recited in claim 10, further comprising the steps of: forming a layer of pad oxide on said substrate prior to forming said trench; forming a layer of silicon nitride on said layer of pad oxide; forming a patterned masking layer on said layer of silicon nitride; and etching said silicon nitride layer, said pad oxide layer, and said substrate to form said trench.
Claim 15
Dependent Claim
18 words
The method, as recited in claim 10, wherein said trench has a predetermined width and a predetermined depth.
Claim 16
Dependent Claim
20 words
The method, as recited in claim 13, wherein the ratio of said depth to said width is greater than two.
Claim 17
Dependent Claim
22 words
The method, as recited in claim 13, wherein said first layer of silicon is approximately one-third of said depth of said trench.
Claim 18
Dependent Claim
22 words
The method, as recited in claim 13, wherein said second layer of silicon is approximately one-third of said depth of said trench.
Claim 19
Dependent Claim
18 words
The method, as recited in claim 10, wherein said first layer of silicon comprises amorphous or polycrystalline silicon.
Claim 20
Dependent Claim
18 words
The method, as recited in claim 10, wherein said second layer of silicon comprises amorphous or polycrystalline silicon.
Claim 21
Independent Claim
96 words
A method of forming a trench isolation on a semiconductor substrate having a trench with side walls and a bottom, comprising the steps of: filling said trench with multiple layers of silicon, said multiple layers including a first layer, at least one intermediate layer and a last layer, the first layer covering the bottom of the trench; oxidizing the first layer of silicon and each intermediate layer of silicon before filling said trench with the next layer of silicon; and oxidizing the last layer of silicon after filling said trench with the last layer of silicon.
Claim 22
Independent Claim
96 words
A method of forming a trench isolation on a semiconductor substrate having a trench with side walls and a bottom, comprising the steps of: filling said trench with multiple layers of silicon, said multiple layers including a first layer, at least one intermediate layer and a last layer, the first layer covering the bottom of the trench; oxidizing the first layer of silicon and each intermediate layer of silicon before filling said trench with the next layer of silicon; and oxidizing the last layer of silicon after filling said trench with the last layer of silicon.
Claim 23
Dependent Claim
30 words
The method, as recited in claim 19, further comprising the step of forming a layer of nitride in said trench prior to filling said trench with said layers of silicon.
Claim 24
Dependent Claim
18 words
The method, as recited in claim 19, wherein said trench has a predetermined width and a predetermined depth.
Claim 25
Dependent Claim
20 words
The method, as recited in claim 21, wherein the ratio of said depth to said width is greater than two.
Claim 26
Dependent Claim
26 words
The method, as recited in claim 21, wherein said first layer comprises amorphous or polycrystalline silicon which is approximately one-third of said depth of said trench.
Claim 27
Dependent Claim
26 words
The method, as recited in claim 21, wherein said intermediate layer comprises amorphous or polycrystalline silicon which is approximately one-third of said depth of said trench.
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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) | 2003-10-24 | 2004-04-24 | 2004-10-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-10-24 | 2008-04-24 | 2008-10-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-10-24 | 2012-04-24 | 2012-10-24 | $7700.00 | Window Closed / Lapsed |