US6429085B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Self-aligned non-selective thin-epi-base silicon germaniun (SiGe) heterojunction bipolar transistor BiCMOS process using silicon dioxide etchback
Assignee: Qualcomm Inc
•
Filing: 2000-09-06
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Granted: 2002-08-06
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Expires: 2020-09-06
Abstract
Abstract A process used in the fabrication of a self-aligned non-selective thin-epi-base silicon germanium (SiGe) heterojunction bipolar transistor (HBT) BiCMOS. The process involves using TEOS or Spin-On-Glass (SOG) silicon dioxide etchback in the fabrication of the SiGe BiCMOS device.
Inventors
- 👤 Jerald Frank Pinter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 17:19
CPC Classifications
H; H10; H10D; H10D10/00; H10D10/01; H10D10/021; H10D84/00; H10D84/01; H10D84/0107; H10D84/0109; H10D84/02; H10D84/03; H10D84/038
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
75 words
A method of fabricating a bipolar transistor, comprising: depositing silicon germanium in and outside a well; forming TEOS silicon dioxide such that at least a portion of the silicon germanium in the well is positioned under TEOS silicon dioxide and at least a portion of silicon germanium outside the well is not positioned under TEOS silicon dioxide; and removing at least a portion of the silicon germanium that is not positioned under TEOS silicon dioxide.
Claim 2
Independent Claim
75 words
A method of fabricating a bipolar transistor, comprising: depositing silicon germanium in and outside a well; forming TEOS silicon dioxide such that at least a portion of the silicon germanium in the well is positioned under TEOS silicon dioxide and at least a portion of silicon germanium outside the well is not positioned under TEOS silicon dioxide; and removing at least a portion of the silicon germanium that is not positioned under TEOS silicon dioxide.
Claim 3
Dependent Claim
33 words
The method of claim 1 , wherein removing at least a portion of the silicon germanium that is not positioned under TEOS silicon dioxide includes removing the silicon germanium located outside the well.
Claim 4
Dependent Claim
45 words
The method of claim 1 , wherein removing at least a portion of the silicon germanium that is not positioned under TEOS silicon dioxide includes removing at least a portion of silicon germanium positioned between the TEOS silicon dioxide and a wall of the well.
Claim 5
Dependent Claim
29 words
The method of claim 1 , wherein removing at least a portion of the silicon germanium that is not positioned under TEOS silicon dioxide includes performing an anisotropic etch.
Claim 6
Dependent Claim
52 words
The method of claim 1 , wherein removing at least a portion of the silicon germanium that is not positioned under TEOS silicon dioxide is performed so as to leave silicon germanium adjacent to a bottom of the well and adjacent to at least a portion of a wall of the well.
Claim 7
Dependent Claim
84 words
The method of claim 1 , wherein forming TEOS silicon dioxide such that at least a portion of the silicon germanium the well is positioned under TEOS silicon dioxide and at least a portion of silicon germanium outside the well is not positioned under TEOS silicon dioxide includes forming the TEOS silicon dioxide such that a portion of the silicon germanium in the well is positioned under TEOS silicon dioxide and the silicon germanium outside the well is not positioned under TEOS silicon dioxide.
Claim 8
Dependent Claim
75 words
The method of claim 1 , wherein forming TEOS silicon dioxide such that at least a portion of the silicon germanium in the well is positioned under TEOS silicon dioxide and at least a portion of silicon germanium outside the well is not positioned under TEOS silicon dioxide includes forming the TEOS silicon dioxide over the deposited silicon dioxide; forming spin-on-glass over the TEOS silicon dioxide; and etching the TEOS silicon dioxide and the spin-on-glass.
Claim 9
Dependent Claim
26 words
The method of claim 1 , wherein depositing silicon germanium in and outside a well includes depositing silicon germanium adjacent to a wall of the well.
Claim 10
Dependent Claim
72 words
The method of claim 8 , wherein forming TEOS silicon dioxide such that at least a portion of the silicon germanium in the well is positioned under TEOS silicon dioxide and at least a portion of silicon germanium outside the well is not positioned under TEOS silicon dioxide includes forming TEOS silicon dioxide such that silicon germanium adjacent to the wall of the well is not positioned under the TEOS silicon dioxide.
Claim 11
Dependent Claim
40 words
The method of claim 1 , wherein removing at least a portion of the silicon germanium that is not positioned under TEOS silicon dioxide causes TEOS silicon dioxide positioned in the well to extend above silicon germanium in the well.
Claim 12
Dependent Claim
28 words
The method of claim 1 , further comprising: forming silicon nitride over a portion of the silicon germanium which is positioned adjacent to a wall of the well.
Claim 13
Dependent Claim
19 words
The method of claim 11 , wherein the formed silicon nitride is adjacent to the wall of the well.
Claim 14
Dependent Claim
22 words
The method of claim 11 , further comprising: removing the TEOS silicon dioxide positioned in the well after forming the silicon nitride.
Claim 15
Dependent Claim
35 words
The method of claim 1 , further comprising: removing the TEOS silicon dioxide positioned in the well after removing at least a portion of the silicon germanium that is not positioned under TEOS silicon dioxide.
Claim 16
Dependent Claim
38 words
The method of claim 14 , further comprising: forming silicon dioxide in a corner of the well over a portion of the silicon germanium left in the well after removing the TEOS silicon dioxide positioned in the well.
Claim 17
Dependent Claim
38 words
The method of claim 14 , further comprising: forming silicon nitride in a corner of the well over a portion of the silicon germanium left in the well after removing the TEOS silicon dioxide positioned in the well.
Claim 18
Dependent Claim
37 words
The method of claim 14 , further comprising: forming polysilicon in a corner of the well over a portion of the silicon germanium left in the well after removing the TEOS silicon dioxide positioned in the well.
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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) | 2005-08-05 | 2006-02-04 | 2006-08-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2009-08-05 | 2010-02-04 | 2010-08-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2013-08-05 | 2014-02-04 | 2014-08-06 | $7700.00 | Window Closed / Lapsed |