Patent US5212112A successfully refreshed from Google Patents.
US5212112A
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US
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Selective epitaxy of silicon in silicon dioxide apertures with suppression of unwanted formation of facets
Assignee: Nokia Bell Labs
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Filing: 1991-05-23
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Granted: 1993-05-18
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Expires: 2011-05-23
Abstract
Abstract In the prior art, selective epitaxial growth (SEG) of semiconductors, performed typically in rectangular windows penetrating through a masking layer located on a major surface of semiconductor substrate, suffers from unwanted facet formation at the corners of the windows--whereby the desirable planar area available for transistor fabrication is reduced. Such facet formation is suppressed--i.e., the area occupied by unwanted facets is reduced--by adding a relatively small lobe penetrating through the masking layer at each corner of each window prior to performing the SEG, whereby transistor packing density can be increased.
Inventors
- 👤 William T. Lynch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:22
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/20; H10P14/24; H10P14/27; H10P14/271; H10P14/29; H10P14/2901; H10P14/2902; H10P14/2905; H10P14/34; H10P14/3402; H10P14/3404; H10P14/3411; H10W; H10W10/00; H10W10/01; H10W10/011; H10W10/018; H10W10/10
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
98 words
A method of selective epitaxial growth of a semiconductor region comprises the steps of (a) forming a window and a lobe in a masking layer located on a major surface of an essentially monocrystalline semiconductor body, the window having a corner defined by an intersection of first and second edges thereof, the lobe being located at said corner, the window and the lobe penetrating through the masking layer to the major surface of the semiconductor body; and (b) epitaxially growing semiconductor in said window and said lobe, whereby the semiconductor region includes both said window and said lobe.
Claim 2
Independent Claim
98 words
A method of selective epitaxial growth of a semiconductor region comprises the steps of (a) forming a window and a lobe in a masking layer located on a major surface of an essentially monocrystalline semiconductor body, the window having a corner defined by an intersection of first and second edges thereof, the lobe being located at said corner, the window and the lobe penetrating through the masking layer to the major surface of the semiconductor body; and (b) epitaxially growing semiconductor in said window and said lobe, whereby the semiconductor region includes both said window and said lobe.
Claim 3
Dependent Claim
36 words
The method of claim 1 in which the lobe has at least a first edge running parallel to a crystallographic direction of the semiconductor body and has two other edges running perpendicular to the first edge.
Claim 4
Dependent Claim
20 words
The method of claim 2 in which the semiconductor is silicon and in which the major surface is oriented (100).
Claim 5
Dependent Claim
21 words
The method of claim 2 or 3 in which the lobe has only one edge running parallel to the crystallographic direction.
Claim 6
Dependent Claim
19 words
The method of claim 4 in which the crystallographic direction is the <110> crystallographic direction of the silicon body.
Claim 7
Dependent Claim
26 words
The method of claim 2 in which step (b) is performed by means of a mixture SiH 2 Cl 2 , HCl and H 2 .
Claim 8
Dependent Claim
24 words
The method of claim 6 in which the mole ratio of SiH 2 Cl 2 to HCl is at least approximately equal to 0.6.
Claim 9
Dependent Claim
21 words
In a method of making an integrated circuit, selectively growing a semiconductor region according to the steps recited in claim 3.
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 |