US5212110A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for forming isolation regions in a semiconductor device
Assignee: Motorola Solutions Inc
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Filing: 1992-05-26
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Granted: 1993-05-18
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Expires: 2012-05-26
Abstract
Abstract A process for fabricating isolation regions in a semiconductor substrate which does not depend upon pattern definition capability. In one embodiment a device isolation region (30) is formed in a semiconductor substrate (12) by first creating a trench (18) in the substrate (12). A single-crystal SiGe layer (24) is formed to overlie the wall surface (20) of the trench (18). A layer of selectively-deposited, single-crystal silicon (26) is formed in the trench (18) using both the bottom surface (22) of the trench (18) and the SiGe layer (24) as a nucleation site for the selective deposition process. After the single-crystal silicon layer (26) is formed, the SiGe layer (24) is selectively removed and the previously occupied space is filled with a dielectric material to form isolation region (30).
Inventors
- 👤 James R. Pfiester
- 👤 Howard C. Kirsch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 11:45
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/20; H10P14/29; H10P14/2901; H10P14/2902; H10P14/2905; H10P14/24; H10P14/27; H10P14/271; H10P14/34; H10P14/3402; H10P14/3404; H10P14/3411; H10P50/00; H10P50/60; H10P50/64; H10P50/642; H10W; H10W10/00; H10W10/01; H10W10/011; H10W10/012; H10W10/0121; H10W10/014; H10W10/10; H10W10/13; H10W10/17; Y; Y10; Y10S; Y10S148/00; Y10S148/05
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
78 words
A method for forming a semiconductor device comprising: providing a substrate having a single-crystal silicon surface; forming a single-crystal SiGe layer overlying a portion of the surface, wherein the SiGe layer contacts the silicon surface at a predetermined point; and selectively forming a single-crystal silicon layer overlying the single-crystal silicon surface and contacting side portions of the SiGe layer, wherein the SiGe provides a seed layer for the formation of the single-crystal silicon layer at said side portions.
Claim 2
Independent Claim
78 words
A method for forming a semiconductor device comprising: providing a substrate having a single-crystal silicon surface; forming a single-crystal SiGe layer overlying a portion of the surface, wherein the SiGe layer contacts the silicon surface at a predetermined point; and selectively forming a single-crystal silicon layer overlying the single-crystal silicon surface and contacting side portions of the SiGe layer, wherein the SiGe provides a seed layer for the formation of the single-crystal silicon layer at said side portions.
Claim 3
Dependent Claim
23 words
The method of claim 1 wherein forming a single-crystal SiGe layer comprises chemical vapor deposition using a gas mixture including Si and Ge.
Claim 4
Independent Claim
63 words
A method for forming a semiconductor device comprising: providing a silicon substrate having a vertical wall surface; forming a single-crystal SiGe sidewall spacer overlying the vertical wall surface; selectively depositing a silicon layer to form a single-crystal silicon region spaced apart from the vertical wall surface by the SiGe spacer; and selectively etching away the SiGe spacer leaving the selectively deposited silicon region.
Claim 5
Independent Claim
63 words
A method for forming a semiconductor device comprising: providing a silicon substrate having a vertical wall surface; forming a single-crystal SiGe sidewall spacer overlying the vertical wall surface; selectively depositing a silicon layer to form a single-crystal silicon region spaced apart from the vertical wall surface by the SiGe spacer; and selectively etching away the SiGe spacer leaving the selectively deposited silicon region.
Claim 6
Dependent Claim
23 words
The method of claim 3 wherein forming a single-crystal SiGe layer comprises chemical vapor deposition using a gas mixture including Si and Ge.
Claim 7
Dependent Claim
22 words
The method of claim 3 wherein selectively etching the SiGe layer comprises wet etching using hydrogen fluoride, hydrogen peroxide and acetic acid.
Claim 8
Dependent Claim
45 words
The method of claim 3 wherein the step of forming a single-crystal SiGe sidewall spacer comprises: depositing a layer of SiGe to overlie the silicon substrate; and anisotropically etching the SiGe layer to form a portion of the SiGe layer on the vertical wall surface.
Claim 9
Independent Claim
84 words
A method for forming a semiconductor device comprising: providing a single-crystalline silicon substrate of a first conductivity type; forming an insulating layer overlying the surface of the substrate; etching a trench into the substrate, the trench having a wall surface; forming a SiGe sidewall layer overlying the wall surface; selectively forming a single-crystal silicon layer in the trench; removing the SiGe sidewall layer leaving a space between the vertical wall surface and the single-crystal silicon layer; and filling the space with a dielectric material.
Claim 10
Independent Claim
84 words
A method for forming a semiconductor device comprising: providing a single-crystalline silicon substrate of a first conductivity type; forming an insulating layer overlying the surface of the substrate; etching a trench into the substrate, the trench having a wall surface; forming a SiGe sidewall layer overlying the wall surface; selectively forming a single-crystal silicon layer in the trench; removing the SiGe sidewall layer leaving a space between the vertical wall surface and the single-crystal silicon layer; and filling the space with a dielectric material.
Claim 11
Dependent Claim
22 words
The method of claim 7 wherein removing the SiGe sidewall layer comprises wet etching using hydrogen fluoride, hydrogen peroxide and acetic acid.
Claim 12
Dependent Claim
41 words
The method of claim 7 wherein the step of filling the space with a dielectric material comprises oxidizing the vertical surface and the single-crystal silicon layer to from an oxide layer electrically isolating the vertical surface from the single-crystal silicon layer.
Claim 13
Dependent Claim
21 words
The method of claim 7 further comprising forming MOS transistors in the single-crystal silicon layer and in the single-crystal silicon substrate.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-05-17 | 1996-11-16 | 1997-05-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-05-17 | 2000-11-16 | 2001-05-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-05-17 | 2004-11-16 | 2005-05-18 | $7700.00 | Window Closed / Lapsed |