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EP0485907A1 Expired / Lapsed EP ⏱️ 0.0 years remaining

Ultrahigh-purity ferroelectric thin film

Assignee: Mitsubishi Materials Corp
•
Filing: 1991-11-08
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Granted: —
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Expires: 2011-11-08
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Abstract

Abstract Disclosed herein is an ultrahigh-purity ferroelectric thin film of Pb-containing ferroelectric represented by the formula Pb 1-x La x (Zr y Ti 1-y ) 1-x/4 O₃ (where Y is 0 or 1 or a decimal smaller than 1), characterized in that the total content of alkali metal impurities therein is less than 1 ppm, or characterized in that the total content of alkali metal impurities therein is less than 0.1 ppm and the total content of U and Th therein is less than 10 ppb. It will find use as infrared sensor, piezoelectric filter, vibrator, laser modulator, optical shutter, capacitor film, nonvolatile memory, etc. owing to its very low level of leakage current.

Inventors

  • 👤 Katsumi C/O Mitsubishi Materials Corp. Ogi
  • 👤 Nobuyuku C/O Mitsubishi Materials Corp. Soyama

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-04 17:05
CPC Classifications
H; H10; H10B; H10B53/00; C; C23; C23C; C23C18/00; C23C18/02; C23C18/12; C23C14/00; C23C14/06; C23C14/08; C23C14/088; C23C16/00; C23C16/22; C23C16/30; C23C16/40; C23C16/409; C23C18/1204; C23C18/1208; C23C18/1216; C30; C30B; C30B29/00; C30B29/10; C30B29/16; C30B29/22; C30B29/32; C30B7/00; C30B7/005; H10P; H10P14/00; H10P14/60; H10P14/63; H10P14/6326; H10P14/6328; H10P14/6329; H10P14/6342; H10P14/69; H10P14/692; H10P14/6938; H10P14/69398

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 50 words
A ferroelectric thin film of Pb-containing ferroelectric represented by the formula Pb 1-x La x (Zr y Ti 1-y ) 1-x/4 O₃ (where Y is 0 or 1 or a decimal smaller than 1), characterized in that the total content of alkali metal impurities therein is less than 1 ppm.
Claim 2
Dependent Claim 39 words
A ferroelectric thin film as defined in claim 1 characterized in that the total content of alkali metal impurities therein is less than 0.1 ppm and the total content of U and Th therein is less than 10 ppb.
Claim 3
Dependent Claim 65 words
A ferroelectric thin film as defined in claim 1 or 2, wherein the Pb-containing ferroelectric is lead titanate (represented by the above formula where x = y = 0), lead titanate zirconate (represented by the above formula where x = 0 and 0 < y < 1), or La-containing lead titanate zirconate (represented by the above formula where x > 0 and y < 1).
Claim 4
Dependent Claim 79 words
A ferroelectric thin film as defined in claims 1 - 3, which is formed from a coating solution prepared by the steps of dissolving organometallic compounds of lead, lanthanum, titanium, and zirconium in an organic solvent, thereby forming a solution in which each metal is bonded to an organic group through oxygen, mixing the solution with a stabilizer, and diluting the solution with a prescribed amount of water for partial hydrolysis to form the metal-oxygen-metal bond in the solution.

References Cited (Backward Citations)

US4963390A Cited

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