US5744853A
Expired / Lapsed
US
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Three dimensional polysilicon capacitor for high density integrated circuit applications
Assignee: GlobalFoundries Singapore Pte Ltd
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Filing: 1997-03-05
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Granted: 1998-04-28
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Expires: 2017-03-05
Abstract
Abstract A three-dimensional polysilicon capacitor for use within integrated circuits and a method by which the three-dimensional polysilicon capacitor is formed. Formed upon a semiconductor substrate is a first polysilicon layer which has a series of apertures formed at least partially through the first polysilicon layer. A conformal insulator layer is then formed upon the first polysilicon layer and into the apertures within the first polysilicon layer. The conformal insulator layer has a series of apertures corresponding to the series of apertures within the first polysilicon layer. A second polysilicon layer is then formed upon the surface of the conformal insulator layer and filling the apertures within the conformal insulator layer. Optionally, the first polysilicon layer may be formed from a multi-coating stack comprising two polysilicon coatings separated by an metal silicide etch stop layer.
Inventors
- 👤 Elgin Kiok Boone Quek
- 👤 Yang Pan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 01:06
CPC Classifications
H; H10; H10D; H10D1/00; H10D1/60; H10D1/68; H10D84/00; H10D84/80; H10D84/811; H10D84/813; Y; Y10; Y10S; Y10S257/00; Y10S257/906
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
160 words
A method for forming a three-dimensional polysilicon capacitor for use in integrated circuits comprising: providing a semiconductor substrate; forming over the semiconductor substrate a first insulator layer; forming upon the first insulator layer without contacting the semiconductor substrate a first polysilicon layer, the first polysilicon layer having a first series of apertures formed at least partially through the first polysilicon layer; forming upon the first polysilicon layer and into the first series of apertures within the first polysilicon layer a conformal insulator layer, the conformal insulator layer having a second series of apertures formed therein corresponding to locations where the conformal insulator layer is formed into the first series of apertures within the first polysilicon layer; and forming upon the conformal insulator layer and completely filing the second series of apertures within the conformal insulator layer a second polysilicon layer, where the areal dimensions of the second polysilicon layer are contained within the areal dimensions of the first polysilicon layer.
Claim 2
Independent Claim
160 words
A method for forming a three-dimensional polysilicon capacitor for use in integrated circuits comprising: providing a semiconductor substrate; forming over the semiconductor substrate a first insulator layer; forming upon the first insulator layer without contacting the semiconductor substrate a first polysilicon layer, the first polysilicon layer having a first series of apertures formed at least partially through the first polysilicon layer; forming upon the first polysilicon layer and into the first series of apertures within the first polysilicon layer a conformal insulator layer, the conformal insulator layer having a second series of apertures formed therein corresponding to locations where the conformal insulator layer is formed into the first series of apertures within the first polysilicon layer; and forming upon the conformal insulator layer and completely filing the second series of apertures within the conformal insulator layer a second polysilicon layer, where the areal dimensions of the second polysilicon layer are contained within the areal dimensions of the first polysilicon layer.
Claim 3
Dependent Claim
21 words
The method of claim 1 wherein the first polysilicon layer has an as-doped resistivity of about 6 to about 9 ohm.micron.
Claim 4
Dependent Claim
33 words
The method of claim 2 wherein the first polysilicon layer is formed from a minimum of a single polysilicon layer formed upon the semiconductor substrate at about 1500 to about 4000 angstroms thickness.
Claim 5
Dependent Claim
41 words
The method of claim 2 wherein the first polysilicon layer is formed from a multi-coating polysilicon layer comprising two polysilicon coatings at about 1000 to about 2000 angstroms thickness each, the two polysilicon coatings being separated by a metal silicide layer.
Claim 6
Dependent Claim
31 words
The method of claim 4 wherein the metal silicide layer is a tungsten silicide layer formed between the two polysilicon coatings at a thickness of about 1000 to about 2000 angstroms.
Claim 7
Dependent Claim
53 words
The method of claim 2 wherein the individual apertures within the first series of apertures formed within the first polysilicon layer are square apertures formed partially through the first polysilicon layer, each square aperture being about 4000 to about 8000 angstroms along each edge and about 1000 to about 2000 angstroms in depth.
Claim 8
Dependent Claim
53 words
The method of claim 2 therein the individual apertures within the first series of apertures formed within the first polysilicon layer are trench apertures formed completely through the first polysilicon layer, the trenches being about 4000 to about 8000 angstroms in width, the trenches being separated by about 4000 to about 8000 angstroms.
Claim 9
Dependent Claim
20 words
The method of claim 1 wherein the conformal insulator layer has a thickness of about 300 to about 600 angstroms.
Claim 10
Dependent Claim
35 words
The method of claim 8 wherein the conformal insulator layer is formed from an insulating material chosen from the group of insulating materials consisting of silicon oxide materials, silicon nitride materials and silicon oxynitride materials.
Claim 11
Dependent Claim
21 words
The method of claim 1 wherein the second polysilicon layer has an as-doped resistivity of about 6 to about 9 ohm.micron.
Claim 12
Dependent Claim
33 words
The method of claim 10 wherein the second polysilicon layer is formed from a minimum of one polysilicon coating formed upon the conformal insulator layer at about 1500 to about 3000 angstroms thickness.
Claim 13
Dependent Claim
44 words
The method of claim 1 wherein at least one layer of the first polysilicon layer and the second polysilicon layer is employed in forming at least one other integrated circuit device structure upon the semiconductor substrate upon which is formed the three-dimensional polysilicon capacitor.
Claim 14
Dependent Claim
154 words
A three-dimensional polysilicon capacitor for use in integrated circuits comprising: a semiconductor substrate; an insulator layer formed over the semiconductor substrate; a first polysilicon layer formed upon the insulator layer without contacting the semiconductor substrate, the first polysilicon layer having a first series of apertures formed at least partially through the first polysilicon layer; a conformal insulator layer formed upon the first polysilicon layer and into the first series of apertures formed within the first polysilicon layer, the conformal insulator layer having a second series of apertures formed therein corresponding to locations where the conformal insulator layer is formed into the first series of apertures within the first polysilicon layer; and a second polysilicon layer formed upon the conformal insulator layer and completely filling the second series of apertures within the conformal insulator layer, where the areal dimensions of the second polysilicon layer are contained within the areal dimensions of the first polysilicon layer.
Claim 15
Dependent Claim
154 words
A three-dimensional polysilicon capacitor for use in integrated circuits comprising: a semiconductor substrate; an insulator layer formed over the semiconductor substrate; a first polysilicon layer formed upon the insulator layer without contacting the semiconductor substrate, the first polysilicon layer having a first series of apertures formed at least partially through the first polysilicon layer; a conformal insulator layer formed upon the first polysilicon layer and into the first series of apertures formed within the first polysilicon layer, the conformal insulator layer having a second series of apertures formed therein corresponding to locations where the conformal insulator layer is formed into the first series of apertures within the first polysilicon layer; and a second polysilicon layer formed upon the conformal insulator layer and completely filling the second series of apertures within the conformal insulator layer, where the areal dimensions of the second polysilicon layer are contained within the areal dimensions of the first polysilicon layer.
Claim 16
Dependent Claim
38 words
The three-dimensional polysilicon capacitor of claim 13 wherein the first polysilicon layer has a resistivity of about 6 to about 9 ohm.micron and the first polysilicon layer has a thickness of about 1500 to about 4000 angstroms thickness.
Claim 17
Dependent Claim
53 words
The three-dimensional polysilicon capacitor of claim 13 wherein the first polysilicon layer is formed from a multi-coating polysilicon layer comprising two polysilicon coatings at about 1000 to about 2000 angstroms thickness each, the two polysilicon coatings being separated by a metal silicide layer at a thickness of about 1000 to about 2000 angstroms.
Claim 18
Dependent Claim
55 words
The three-dimensional polysilicon capacitor of claim 13 wherein the individual apertures within the first series of apertures formed within the first polysilicon layer are square apertures formed partially through the first polysilicon layer, each square aperture being about 4000 to about 8000 angstroms along each edge and about 1000 to about 2000 angstroms in depth.
Claim 19
Dependent Claim
55 words
The three-dimensional polysilicon capacitor of claim 13 wherein the individual apertures within the first series of apertures formed within the first polysilicon layer are trench apertures formed completely through the first polysilicon layer, the trenches being about 4000 to about 8000 angstroms in width, the trenches being separated by about 4000 to about 8000 angstroms.
Claim 20
Dependent Claim
22 words
The three-dimensional polysilicon capacitor of claim 13 wherein the conformal insulator layer has a thickness of about 300 to about 600 angstroms.
Claim 21
Dependent Claim
50 words
The three-dimensional polysilicon capacitor of claim 13 wherein the second polysilicon layer has a resistivity of about 6 to about 9 ohm.micron and the second polysilicon layer is formed from a minimum of one polysilicon layer formed upon the conformal insulator layer at about 1500 to about 3000 angstroms thickness.
Claim 22
Dependent Claim
46 words
The three-dimensional polysilicon capacitor of claim 13 wherein at least one layer of the first polysilicon layer and the second polysilicon layer is employed in forming at least one other integrated circuit device structure upon the semiconductor substrate upon which is formed the three-dimensional polysilicon capacitor.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-04-27 | 2001-10-27 | 2002-04-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-04-27 | 2005-10-27 | 2006-04-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-04-27 | 2009-10-27 | 2010-04-28 | $7700.00 | Window Closed / Lapsed |