Patent US5428645A successfully refreshed from Google Patents.
EP0210050A2
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Semiconductor strain gauges
Assignee: Flopetrol Services Inc
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Filing: 1986-07-16
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Granted: —
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Expires: 2006-07-16
Abstract
Abstract The present invention discloses a semiconductor strain gauge (7b) which is formed from a thin layer of semiconductor substrate (1) by means of an insulating layer (6,7a). The invention also discloses a method of manufacturing such a strain gauge utilising silicon as the semiconductor material. The method employs laser recrystallisation technology to recrystallise a thin layer of polycrystalline silicon (7) formed over an insulating layer (6) on a silicon substrate (1), in order to produce a thin layer of monocrystalline silicon (7b) isolated from the subsrate. This is utilised as a strain gauge. The advantages of the strain gauges in accordance with the invention include the fact that they can be operated over a wide temperature range, as there is no diode junction formed between the gauge and substrate. They can thus be used in many situations were semiconductor strain gauges have not before been useful.
Inventors
- 👤 Jean Marie Zoning Ind. De Wauthier Braine Labbe
- 👤 Francis Zoning Ind. De Wauthier Braine Jasper
- 👤 Peter Zoning Ind. De Wauthier Braine Bassett
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-25 23:34
CPC Classifications
G; G01; G01L; G01L1/00; G01L1/20; G01L1/22; G01L1/2287; G01L1/2293
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
37 words
A semiconductor strain gauge (7b) formed on a semiconductor substrate (1) characterised in that the strain gauge (7b) comprises a thin layer of semiconductor material isolated from the semiconductor substrate (1) by an insulating layer (6, 7a).
Claim 2
Dependent Claim
37 words
A semiconductor strain gauge (7b) formed on a semiconductor substrate (1) characterised in that the strain gauge (7b) comprises a thin layer of semiconductor material isolated from the semiconductor substrate (1) by an insulating layer (6, 7a).
Claim 3
Dependent Claim
16 words
A semiconductor strain gauge in accordance with claim 1, wherein the semiconductor material is munocrystalline silicon.
Claim 4
Dependent Claim
17 words
A semiconductor strain gauge in accordance with claim wherein the insulating layer (6,7a) is silicon dioxide (Si02).
Claim 5
Independent Claim
56 words
A method of manufacturing a silicon strain gauge (7b) comprising the steps of; forming an insulating layer (6) on the surface of a monocrystalline silicon substrate (1): forming a thin monocrystalline silicon layer (7b) over the insulating layer (6) isolated from the silicon substrate (1) whereby the thin monocrystalline silicon layer (7b) constitutes a strain gauge.
Claim 6
Independent Claim
56 words
A method of manufacturing a silicon strain gauge (7b) comprising the steps of; forming an insulating layer (6) on the surface of a monocrystalline silicon substrate (1): forming a thin monocrystalline silicon layer (7b) over the insulating layer (6) isolated from the silicon substrate (1) whereby the thin monocrystalline silicon layer (7b) constitutes a strain gauge.
Claim 7
Dependent Claim
115 words
A method in accordance with claim 4, wherein the formation of the thin monocrystalline silicon layer (7b) comprises the further steps of; forming windows in the insulating layer (6) to expose areas (la) of monocrystalline silicon substrate (1); depositing a layer of poly crystalline silicon (7) over the insulating layer (6) and exposed areas (1a); recrystallising the polycrystalline silicon layer (7) such that the crystal orientation of the exposed areas (1a) is copied whereby a thin layer of monocrystalline silicon (7) is formed, treating the thin monocrystalline silicon layer (7) so as to form insulating areas (7a) which together with the insulating layer (6) isolate a thin monocrystalline silicon layer (7b) from the substrate (1).
Claim 8
Dependent Claim
88 words
A method in accordance with claim 5, wherein the step of recrystallising the polycrystalline silicon layer (7) comprises the further steps of; first forming anti-reflecting strips (8a) over the polycrystalline silicon layer (7) whereby to introduce a particular temperature profile (11) during recrystallisation; initiationglaser recrystallisation in the windows (la) where the polycrystalline silicon layer (7) is in contact with the exposed areas (1a) of substrate (1), whereby the recrystallisation front moves over the silicon layer (7) giving monocrystals between antireflecting strips (8a), and grain boundaries beneath antireflecting strips.
Claim 9
Independent Claim
46 words
A method in accordance with claims 5 or 6 wherein the monocrystalline layer (7) is treated by oxidising the grain boundaries and windows to form insulating areas (7a) of silicon dioxide (Si02) which together with insulating layer 6 isolate the monocrystalline area (7b) from the substrate.
Claim 10
Independent Claim
20 words
A method in accordance with any of claims 4 to 7 wherein the insulating layer 6 is of silicon dioxide.
Claim 11
Independent Claim
44 words
A method in accordance with any of claims 4 to 8 further comprising the step of doping the strain gauge (7b) to increase its conductivity, and adding contacts (18) to the strain gauge (7b) so that it may be utilised in an electrical circuit.
References Cited (Backward Citations)
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