US5081061A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Manufacturing ultra-thin dielectrically isolated wafers
Assignee: Intersil Corp
•
Filing: 1991-03-07
•
Granted: 1992-01-14
•
Expires: 2011-03-07
Abstract
Abstract A method including filling etched moats with a first dielectric layer and layer of polycrystalline material and planarizing. A second dielectric layer is formed on the first polycrystalline layer and a second layer of polycrystalline is formed on the second dielectric layer to form a handle. The starting material is then thinned to produce the dielectric isolated islands. Device forming steps are then performed. Finally, the handle is removed leaving a wafer having a thickness defined by the planarized surface of the first polycrystalline layer and the top surface of the first wafer.
Inventors
- 👤 George V. Rouse
- 👤 Paul S. Reinecke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 09:08
CPC Classifications
H; H10; H10W; H10W10/00; H10W10/01; H10W10/011; H10W10/019; H10W10/10; Y; Y10; Y10S; Y10S438/00; Y10S438/928; Y10S438/977
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
143 words
A method of fabricating dielectrically isolated, integrated circuits in ultra-thin wafers comprising: forming moats in a first surface of a first wafer having a first thickness; forming a first dielectric layer on said first surface and said moats; depositing a first polycrystalline layer on said first dielectric layer to fill said moats and planarizing to form a planar surface; depositing a second dielectric layer on said first polycrystalline layer; forming a handle on said second dielectric layer; thinning said first wafer from a second surface to form dielectrically isolated islands at a third surface of said first wafer; performing device formation steps on said third surface; and removing said handle down to said second dielectric layer to produce a wafer having a second thickness substantially defined by said planar surface of said first polycrystalline layer and said third surface of said first wafer.
Claim 2
Independent Claim
143 words
A method of fabricating dielectrically isolated, integrated circuits in ultra-thin wafers comprising: forming moats in a first surface of a first wafer having a first thickness; forming a first dielectric layer on said first surface and said moats; depositing a first polycrystalline layer on said first dielectric layer to fill said moats and planarizing to form a planar surface; depositing a second dielectric layer on said first polycrystalline layer; forming a handle on said second dielectric layer; thinning said first wafer from a second surface to form dielectrically isolated islands at a third surface of said first wafer; performing device formation steps on said third surface; and removing said handle down to said second dielectric layer to produce a wafer having a second thickness substantially defined by said planar surface of said first polycrystalline layer and said third surface of said first wafer.
Claim 3
Dependent Claim
27 words
A method according to claim 1, wherein said planarizing step and said thinning step are performed to form a wafer having said second thickness below 7 mils.
Claim 4
Dependent Claim
38 words
A method according to claim 1, wherein said removing step includes grinding said handle for a substantial portion of its thickness and etching the remaining portion of said handle using said second dielectric layer as a etching stop.
Claim 5
Dependent Claim
22 words
A method according to claim 1 wherein said handle is formed by depositing a second polycrystalline layer on said second dielectric layer.
References Cited (Backward Citations)
US3508980A
Cited
US3689357A
Cited
JPS5330284A
Cited
JPS5511347A
Cited
JPS57102044A
Cited
JPS5756944A
Cited
JPS5895836A
Cited
JPS5918654A
Cited
JPS6196748A
Cited
JPS6248040A
Cited
JPS62124753A
Cited
JPS63219138A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-01-13 | 1995-07-15 | 1996-01-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-01-13 | 1999-07-15 | 2000-01-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-01-13 | 2003-07-15 | 2004-01-14 | $7700.00 | Window Closed / Lapsed |