US5141878A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silicon photodiode for monolithic integrated circuits and method for making same
Assignee: Nokia Bell Labs
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Filing: 1990-04-02
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Granted: 1992-08-25
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Expires: 2010-04-02
Abstract
Abstract An integrated photodiode is formed by providing a silicon substrate with a deep recessed tub in excess of about 20 microns, forming an isolated p-n junction on the peripheral tub surfaces, and selectively epitaxially filling the tub with intrinsic silicon. A desired monolithic integrated circuit is fabricated outside the tub periphery using conventional VLSI techniques. A photodiode electrode structure within the tub periphery can be fabricated at the same time as other monolithic circuit components are formed.
Inventors
- 👤 Janet L. Benton
- 👤 Renuka P. Jindal
- 👤 Ya-Hong Xie
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 04:58
CPC Classifications
H; H10; H10F; H10F77/00; H10F77/10; H10F77/14; H10F77/147; H10F39/00; H10F39/10; H10F39/103; Y; Y02; Y02E; Y02E10/00; Y02E10/50
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
145 words
A method for making a silicon monolithic integrated circuit including an integral photodiode comprising the steps of: providing a silicon substrate having a semiconducting (100) oriented silicon surface; forming in said semiconducting (100) oriented silicon surface a recessed tub having a depth in excess of about 20 microns underlying the region in which said photodiode is to be made, said tub having a peripheral surface including a bottom surface; a plurality of peripheral sidewalls along the 111-axis of the silicon and a peripheral edge, forming a p-n junction over the peripheral surface of said tub including said peripheral sidewalls; filling said tub region with epitaxially grown silicon; forming a monolithic integrated circuit on the region of said substrate outside the peripheral edge of said tub; and simultaneously or separately forming a photodiode on the region of said substrate within the peripheral edge of said tub.
Claim 2
Independent Claim
145 words
A method for making a silicon monolithic integrated circuit including an integral photodiode comprising the steps of: providing a silicon substrate having a semiconducting (100) oriented silicon surface; forming in said semiconducting (100) oriented silicon surface a recessed tub having a depth in excess of about 20 microns underlying the region in which said photodiode is to be made, said tub having a peripheral surface including a bottom surface; a plurality of peripheral sidewalls along the 111-axis of the silicon and a peripheral edge, forming a p-n junction over the peripheral surface of said tub including said peripheral sidewalls; filling said tub region with epitaxially grown silicon; forming a monolithic integrated circuit on the region of said substrate outside the peripheral edge of said tub; and simultaneously or separately forming a photodiode on the region of said substrate within the peripheral edge of said tub.
Claim 3
Dependent Claim
16 words
The method of claim 1 including the step of planarizing the substrate after filling the tub.
Claim 4
Dependent Claim
35 words
The method of claim 1 wherein said photodiode is formed by depositing on the surface of said epitaxially grown silicon within said tub region a collection electrode comprising a grid of interconnected elongated conductive regions.
Claim 5
Dependent Claim
28 words
The method of claim 3 wherein said collection electrode is spaced from the peripheral edge of said tub region by a spacing in excess of about 20 microns.
References Cited (Backward Citations)
FR2481519A1
Cited
EP0067566A2
Cited
JPS61241275A
Cited
US4904607A
Cited
US4956304A
Cited
US4972244A
Cited
US5010018A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-08-25 | 1996-02-24 | 1996-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-08-25 | 2000-02-24 | 2000-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-08-25 | 2004-02-24 | 2004-08-25 | $7700.00 | Window Closed / Lapsed |