Patent US6008104A successfully refreshed from Google Patents.
US6008104A
Expired / Lapsed
US
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Method of fabricating a trench capacitor with a deposited isolation collar
Assignee: Siemens AG
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Filing: 1998-04-06
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Granted: 1999-12-28
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Expires: 2018-04-06
Abstract
Abstract An improved trench capacitor is achieved by providing a node dielectric that lines the collar and sidewalls of the bottom of the trench. Further, the trench capacitor includes a lower portion having a diameter that is substantially the about same or greater than that of the upper portion.
Inventors
- 👤 Martin Schrems
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 12:32
CPC Classifications
H; H10; H10B; H10B12/00; H10B12/01; H10B12/02; H10B12/03; H10B12/038
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
121 words
A method of fabricating a trench capacitor comprising: forming a trench in a substrate; depositing in a lower portion of the trench, a filler material; depositing a dielectric collar in an upper portion of the trench above the filler material and on sidewalls of the trench to form a trench collar; removing the filler material from the bottom portion of the trench; forming a node dielectric that lines the collar and trench sidewalls at the bottom portion of the trench; and filling the trench with a doped semiconductor material that serves as an electrode of the trench capacitor, wherein the diameter of the lower portion of the trench is effectively at least equal to about the upper portion of the trench.
Claim 2
Independent Claim
121 words
A method of fabricating a trench capacitor comprising: forming a trench in a substrate; depositing in a lower portion of the trench, a filler material; depositing a dielectric collar in an upper portion of the trench above the filler material and on sidewalls of the trench to form a trench collar; removing the filler material from the bottom portion of the trench; forming a node dielectric that lines the collar and trench sidewalls at the bottom portion of the trench; and filling the trench with a doped semiconductor material that serves as an electrode of the trench capacitor, wherein the diameter of the lower portion of the trench is effectively at least equal to about the upper portion of the trench.
Claim 3
Dependent Claim
28 words
The method as recited in claim 1, wherein the step of depositing a dielectric collar includes the step of depositing the dielectric collar by employing chemical vapor deposition.
Claim 4
Dependent Claim
23 words
The method as recited in claim 1, wherein the step of depositing a dielectric collar includes the step of depositing an oxide layer.
Claim 5
Dependent Claim
22 words
The method as recited in claim 3, wherein the oxide layer is between about 10 nm to about 50 nm in thickness.
Claim 6
Dependent Claim
21 words
The method as recited in claim 1, further comprises the step of annealing the dielectric collar to densify the dielectric collar.
Claim 7
Dependent Claim
27 words
The method as recited in claim 1, further comprises the step of diffusing oxygen through the dielectric collar to form a thermal oxide below the dielectric collar.
Claim 8
Dependent Claim
33 words
The method as recited in claim 1, wherein the step of forming a trench in a substrate includes the step of etching the trench to a final depth in a single etching process.
Claim 9
Dependent Claim
37 words
The method as recited in claim 1, wherein the step of depositing in a lower portion of the trench a filler material includes the step of depositing the filler material including one of polysilicon and amorphous silicon.
Claim 10
Independent Claim
89 words
A method of fabricating a trench collar for a trench capacitor comprising: forming a trench in a substrate; depositing a sacrificial filler material in a lower portion of the trench; depositing a dielectric collar in an upper portion of the trench above the filler material and on sidewalls of the trench to form a trench collar; and removing the filler material from the bottom portion of the trench such that the lower portion of the trench is effectively at least equal to about the upper portion of the trench.
Claim 11
Independent Claim
89 words
A method of fabricating a trench collar for a trench capacitor comprising: forming a trench in a substrate; depositing a sacrificial filler material in a lower portion of the trench; depositing a dielectric collar in an upper portion of the trench above the filler material and on sidewalls of the trench to form a trench collar; and removing the filler material from the bottom portion of the trench such that the lower portion of the trench is effectively at least equal to about the upper portion of the trench.
Claim 12
Dependent Claim
48 words
The method as recited in claim 9, further comprises the steps of forming a node dielectric that lines the collar and trench sidewalls at the bottom portion of the trench; and filling the trench with a doped semiconductor material that serves as an electrode of the trench capacitor.
Claim 13
Dependent Claim
28 words
The method as recited in claim 9, wherein the step of depositing a dielectric collar includes the step of depositing the dielectric collar by employing chemical vapor deposition.
Claim 14
Dependent Claim
23 words
The method as recited in claim 9, wherein the step of depositing a dielectric collar includes the step of depositing an oxide layer.
Claim 15
Dependent Claim
22 words
The method as recited in claim 12, wherein the oxide layer is between about 10 nm to about 50 nm in thickness.
Claim 16
Dependent Claim
21 words
The method as recited in claim 9, further comprises the step of annealing the dielectric collar to densify the dielectric collar.
Claim 17
Dependent Claim
27 words
The method as recited in claim 9, further comprises the step of diffulsing oxygen through the dielectric collar to form a thermal oxide below the dielectric collar.
Claim 18
Dependent Claim
33 words
The method as recited in claim 9, wherein the step of forming a trench in a substrate includes the step of etching the trench to a final depth in a single etching process.
Claim 19
Dependent Claim
38 words
The method as recited in claim 9, wherein the step of depositing a sacrificial filler material in a lower portion of the trench includes the step of depositing the filler material including one of polysilicon and amorphous silicon.
References Cited (Backward Citations)
US5658816A
Cited
US5656535A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-12-27 | 2003-06-28 | 2003-12-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-12-27 | 2007-06-28 | 2007-12-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-12-27 | 2011-06-28 | 2011-12-28 | $7700.00 | Window Closed / Lapsed |