US5567979A
Expired / Lapsed
US
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Oriented ferroelectric thin-film element and manufacturing method therefor
Assignee: EpiPhotonics Corp
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Filing: 1994-05-27
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Granted: 1996-10-22
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Expires: 2014-05-27
Abstract
Abstract A buffer layer having crystal orientation in a (111) face is formed on a semiconductor single-crystal (100) substrate and a ferroelectric thin film having crystal orientation in a (111) or (0001) face is then formed over the buffer layer. The buffer layer is preferably formed of MgO at a temperature ranging from 20 to 600° C. and at a rate ranging from 0.5 to 50 Å/sec. The thus formed ferroelectric thin film has its axes of polarization aligned in one direction. Using the oriented ferroelectric thin-film device, highly functional nonvolatile memories, capacitors or optical modulators can be fabricated on semiconductor substrates.
Inventors
- 👤 Keiichi Nashimoto
- 👤 Atsushi Masuda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 03:17
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/03; G02F1/05; G02F1/055; G02F1/0553; H; H10; H10D; H10D62/00; H10D62/40; H10D62/405; H10D64/00; H10D64/60; H10D64/66; H10D64/68; H10D64/689; H10D1/00; H10D1/60; H10D1/68; H10D1/682; H10D1/684
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
61 words
An oriented ferroelectric thin film element comprising: a semiconductor single crystal (100) substrate; a buffer layer having a crystal orientation of (111) and random in-plane directions, said buffer layer being provided on said semiconductor single-crystal substrate; and a ferroelectric thin film having a crystal orientation of one of (111) and (0001), said ferroelectric thin film being provided on said buffer layer.
Claim 2
Dependent Claim
61 words
An oriented ferroelectric thin film element comprising: a semiconductor single crystal (100) substrate; a buffer layer having a crystal orientation of (111) and random in-plane directions, said buffer layer being provided on said semiconductor single-crystal substrate; and a ferroelectric thin film having a crystal orientation of one of (111) and (0001), said ferroelectric thin film being provided on said buffer layer.
Claim 3
Dependent Claim
24 words
An oriented ferroelectric thin-film element according to claim 1, wherein said semiconductor single-crystal substrate comprises one of an elemental semiconductor and a compound semiconductor.
Claim 4
Dependent Claim
59 words
An oriented ferroelectric thin-film element according to claim 2, wherein said semiconductor single-crystal (100) substrate comprises one of elemental semiconductors Si, Ge, and diamond, III-V element compound semiconductors AlAs, AlSb, AlP, GaAs, GaSb, InP, InAs, InSb, AlGaP, AlInP, AlGaAs, AlInAs, AlAsSb, GaInAs, GaInSb, GaAsSb, and InAsSb, and II-VI compound semiconductors ZnS, ZnSe, ZnTe, CdSe, CdTe, HgSe, HgTe, and CdS.
Claim 5
Dependent Claim
27 words
An oriented ferroelectric thin-film element according to claim 1, wherein said buffer layer comprises one of MgO, MgAl 2 O 4 , and Y-stabilized ZrO 2 .
Claim 6
Dependent Claim
20 words
An oriented ferroelectric thin-film element according to claim 1, wherein said ferroelectric thin film comprises an ABO 3 -type oxide.
Claim 7
Dependent Claim
60 words
An oriented ferroelectric thin-film element according to claim 5, wherein said ABO 3 -type oxide is one of BaTiO 3 , PbTiO 3 , Pb 1-x La x (Zr 1-y Ti y ) 1-x/4 O 3 (PZT, PLT, and PLZT), Pb(Mg 1/3 Nb 2/3 )O 3 , KNbO 3 , LiNbO 3 , LiTaO 3 , and substituted derivatives thereof.
Claim 8
Dependent Claim
34 words
An oriented ferroelectric thin-film element according to claim , wherein said buffer layer is formed at a temperature ranging from 20° to 600° C. and at a rate ranging from 0.5 to 50 Å/sec.
Claim 9
Dependent Claim
23 words
An oriented ferroelectric thin-film element according to claim 1, wherein a thickness of said buffer layer is from 10 to 10 5 Å.
Claim 10
Dependent Claim
25 words
An oriented ferroelectric thin-film element according to claim 1, wherein a thickness of said ferroelectric thin film is from 10 2 to 10 5 Å.
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