US5195017A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for forming a polysilicon to polysilicon capacitor and apparatus formed therefrom
Assignee: Texas Instruments Inc
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Filing: 1991-12-16
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Granted: 1993-03-16
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Expires: 2011-12-16
Abstract
Abstract A first polysilicon layer (18) is initially deposited onto a layer of field oxide (16). A dielectric (26) is formed on a portion of the first polysilicon layer (18). A second polysilicon layer (28) is deposited over the dielectric (26) and the first polysilicon layer (18). After the selective deposition of a mask (30) on to the second polysilicon layer (28), the polysilicon layers (18, 28) are anistropically etched to form a polysilicon to polysilicon capacitor (34) and a contact (36) of the capacitor (34). The dielectric (26) functions as an insulator for the capacitor (34) and as a barrier during anisotropic etching for protecting the underlying polysilicon layer (18).
Inventors
- 👤 William K. McDonald
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 21:22
CPC Classifications
H; H10; H10D; H10D1/00; H10D1/60; H10D1/68
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
61 words
A polysilicon to polysilicon capacitor, which comprising: a first polysilicon layer deposited on a substrate; an interlevel dielectric pattern formed on a portion of said first polysilicon layer; and a second polysilicon layer having two portions selectively formed on said first polysilicon layer and said interlevel dielectric pattern to form a polysilicon to polysilicon capacitor and a contact for the capacitor.
Claim 2
Dependent Claim
61 words
A polysilicon to polysilicon capacitor, which comprising: a first polysilicon layer deposited on a substrate; an interlevel dielectric pattern formed on a portion of said first polysilicon layer; and a second polysilicon layer having two portions selectively formed on said first polysilicon layer and said interlevel dielectric pattern to form a polysilicon to polysilicon capacitor and a contact for the capacitor.
Claim 3
Dependent Claim
59 words
The capacitor as recited in claim 1, wherein one of said two portions of said second polysilicon layer is spaced apart from said first polysilicon layer to form said capacitor and wherein the other of said two portions of said second polysilicon layer contacts a portion of said dielectric pattern and said first polysilicon layer to form said contact.
Claim 4
Dependent Claim
32 words
The capacitor as recited in claim 1 and further comprising a transistor formed on the substrate and spaced from said capacitor, said capacitor and said transistor formed during the same processing steps.
Claim 5
Dependent Claim
14 words
The capacitor as recited in claim 3, wherein said transistor comprises a CMOS transistor.
Claim 6
Dependent Claim
14 words
The capacitor as recited in claim 3, wherein said transistor comprises a BICMOS transistor.
Claim 7
Dependent Claim
23 words
The capacitor as recited in claim 1, wherein said substrate is a layer of field oxide deposited onto a layer of silicon wafer.
Claim 8
Dependent Claim
18 words
The capacitor as recited in claim 1, further comprising an arsenic dopant implanted within said first polysilicon layer.
Claim 9
Dependent Claim
20 words
The capacitor as recited in claim 1, wherein said interlevel dielectric pattern comprises a layer of oxide and silicon nitride.
Claim 10
Dependent Claim
18 words
The capacitor as recited in claim 1, further comprising a phosphorous dopant diffused within said second polysilicon layer.
References Cited (Backward Citations)
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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) | 1996-03-15 | 1996-09-14 | 1997-03-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-03-15 | 2000-09-14 | 2001-03-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-03-15 | 2004-09-14 | 2005-03-16 | $7700.00 | Window Closed / Lapsed |