US5418216A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Superconducting thin films on epitaxial magnesium oxide grown on silicon
Assignee: Individual
•
Filing: 1992-05-15
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Granted: 1995-05-23
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Expires: 2012-05-15
Abstract
Abstract A structure having a silicon substrate with an epitaxially grown magnesium oxide layer on a surface onto which is epitaxially grown, either directly or on an intermediary layer, a layer of high temperature superconducting material.
Inventors
- 👤 David K. Fork
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 01:44
CPC Classifications
C; C30; C30B; C30B23/00; C30B23/02; C30B29/00; C30B29/10; C30B29/16; C30B29/22; C30B29/225; H; H10; H10N; H10N60/00; H10N60/01; H10N60/0268; H10N60/0296; H10N60/0576; H10N60/0632
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
46 words
A method of forming a superconducting layer, comprising the steps of: epitaxially depositing an MgO layer onto silicon wherein all of the crystal axes of said MgO layer are aligned with the crystal axes of said silicon; and depositing a superconducting layer onto said MgO layer.
Claim 2
Independent Claim
46 words
A method of forming a superconducting layer, comprising the steps of: epitaxially depositing an MgO layer onto silicon wherein all of the crystal axes of said MgO layer are aligned with the crystal axes of said silicon; and depositing a superconducting layer onto said MgO layer.
Claim 3
Dependent Claim
50 words
A method as recited in claim 1 wherein said silicon has a surface, said silicon's surface has a native oxide layer and therefore prior to said step of depositing said epitaxial MgO layer onto said silicon, said method comprises the step of: removing said native oxide from said silicon's surface.
Claim 4
Dependent Claim
21 words
A method as recited in claim 2 further comprising the step of: providing a hydrogen terminated surface on said silicon's surface.
Claim 5
Dependent Claim
34 words
A method as recited in claim 3 wherein said step of removing said native oxide from said silicon's surface and providing a hydrogen terminated surface on said silicon's surface utilizes a spin etching technique.
Claim 6
Dependent Claim
25 words
A method as recited in claim 1 wherein said step of depositing said epitaxial MgO layer onto said silicon utilizes a pulsed laser deposition technique.
Claim 7
Dependent Claim
17 words
A method as recited in claim 5 further comprising the step of utilizing a magnesium metal target.
Claim 8
Dependent Claim
17 words
A method as recited in claim 5 further comprising the step of utilizing a magnesium oxide target.
Claim 9
Dependent Claim
28 words
A method as recited in claim 5 wherein said pulsed laser deposition technique is performed with an O 2 pressure between 1×10 -2 Torr and 2×10 -6 Torr.
Claim 10
Dependent Claim
25 words
A method as recited in claim 1 wherein said step of depositing said epitaxial MgO layer onto said silicon utilizes a molecular beam epitaxy technique.
Claim 11
Dependent Claim
25 words
A method as recited in claim 1 wherein said step of depositing said epitaxial MgO layer onto said silicon utilizes a chemical vapor deposition technique.
Claim 12
Dependent Claim
25 words
A method as recited in claim 1 wherein said step of depositing said epitaxial MgO layer onto said silicon utilizes a electron beam evaporation technique.
Claim 13
Dependent Claim
23 words
A method as recited in claim 1 wherein said step of depositing said epitaxial MgO layer onto said silicon utilizes a sputtering technique.
Claim 14
Dependent Claim
23 words
A method as recited in claim 1 wherein said superconducting layer is a thin film of YBa 2 Cu 3 O 7-8 .
Claim 15
Dependent Claim
15 words
A method as recited in claim 1 wherein said superconducting layer is an oxide superconductor.
Claim 16
Dependent Claim
22 words
A method as in claim 13 in which yttrium is replaced by Nd, Sm, Eu, Gd, Dy, Ho, Er, Yb, or Lu.
Claim 17
Dependent Claim
19 words
A method as in claim 13 in which Ytrium is replaced by Pr, thereby providing a semiconducting thin film.
Claim 18
Dependent Claim
55 words
A method as recited in claim 13 wherein prior to the step of depositing said YB a Cu 3 O 7- δ thin film, said method comprises the step of: depositing an intermediate layer on said MgO layer, said intermediate layer selected from SrTiO 3 , BaTiO 3 , CaTiO 3 or LaAlO 3 .
Claim 19
Dependent Claim
25 words
A method as recited in claim 1 wherein said MgO layer is deposited on said silicon at a temperature between 300° C. and 600° C.
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