US5326718A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for manufacturing a laterally limited, single-crystal region on a substrate and the employment thereof for the manufacture of an MOS transistor and a bipolar transistor
Assignee: Infineon Technologies AG
•
Filing: 1992-09-23
•
Granted: 1994-07-05
•
Expires: 2012-09-23
Abstract
Abstract A method for the manufacture of a laterally limited single crystal region that is suitable for use as an active part of a transistor.
Inventors
- 👤 Helmut Klose
- 👤 Thomas Meister
- 👤 Hans-Willi Meul
- 👤 Reinhard Stengl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 02:14
CPC Classifications
H; H10; H10D; H10D10/00; H10D10/01; H10D10/051; H10D10/054; H10D30/00; H10D30/01; H10D30/021; H10D30/027; H10D30/0278; H10P; H10P14/00; H10P14/20; H10P14/27; H10P14/271; H10P14/29; H10P14/2901; H10P14/2902; H10P14/2905; H10P14/32; H10P14/3202; H10P14/3204; H10P14/3211; H10P14/3238; H10P14/3242; H10P14/3244; H10P14/3251; H10P14/34; H10P14/3402; H10P14/3404; H10P14/3411; Y; Y10; Y10S; Y10S148/00; Y10S148/011
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
185 words
A method for manufacturing a laterally limited, single-crystal region on a substrate, comprising the steps of: a) providing a substrate made of a single-crystal material; b) forming a first layer on a surface of the substrate, said first layer being selectively etchable with respect to the substrate and comprising SiO 2 ; c) forming a second layer on the first layer, the second layer being selectively etchable with respect to the first layer and comprising polycrystalline silicon; d) providing an opening in the first and second layers so as to expose an area on the surface of the substrate; e) covering surfaces and side walls of the second layer with a third layer; f) selectively etching the first layer with respect to the substrate and the second layer so as to provide an undercut between the second layer and the surface of the substrate, the third layer resisting the etchings of the first layer; and g) forming a single-crystal region on the exposed surface of the substrate by selective epitaxy, no nucleation occurring at the surface of the third layer in the selective epitaxy step.
Claim 2
Independent Claim
185 words
A method for manufacturing a laterally limited, single-crystal region on a substrate, comprising the steps of: a) providing a substrate made of a single-crystal material; b) forming a first layer on a surface of the substrate, said first layer being selectively etchable with respect to the substrate and comprising SiO 2 ; c) forming a second layer on the first layer, the second layer being selectively etchable with respect to the first layer and comprising polycrystalline silicon; d) providing an opening in the first and second layers so as to expose an area on the surface of the substrate; e) covering surfaces and side walls of the second layer with a third layer; f) selectively etching the first layer with respect to the substrate and the second layer so as to provide an undercut between the second layer and the surface of the substrate, the third layer resisting the etchings of the first layer; and g) forming a single-crystal region on the exposed surface of the substrate by selective epitaxy, no nucleation occurring at the surface of the third layer in the selective epitaxy step.
Claim 3
Dependent Claim
25 words
The method of claim 1, comprising the further step of doping the single-crystal region in situ by adding compounds containing dopant in the selective epitaxy.
Claim 4
Dependent Claim
13 words
The method of claim 2, wherein the substrate is made of single-crystal silicon.
Claim 5
Dependent Claim
13 words
The method of claim 1, wherein the substrate is made of single-crystal silicon.
Claim 6
Dependent Claim
20 words
The method of claim 1, wherein the single-crystal region is formed of Si l-x GE x , with 0.2 <x<0.4.
Claim 7
Dependent Claim
15 words
The method of claim 1, wherein the third layer comprises Si 3 N 4 .
Claim 8
Dependent Claim
20 words
The method of claim 1, comprising the further step of completely removing the third layer after the selective epitaxy step.
References Cited (Backward Citations)
EP0042698A2
Cited
US4530149A
Cited
US4529455A
Cited
US4824794A
Cited
US4832837A
Cited
DE3825701A1
Cited
US4786615A
Cited
US4996581A
Cited
US5204276A
Cited
US5024957A
Cited
US4975381A
Cited
EP0418422A1
Cited
EP0430279A2
Cited
US5126285A
Cited
US5028557A
Cited
US5147809A
Cited
US5198375A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-07-04 | 1998-01-03 | 1998-07-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-07-04 | 2002-01-03 | 2002-07-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-07-04 | 2006-01-03 | 2006-07-05 | $7700.00 | Window Closed / Lapsed |