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US4475091A Expired / Lapsed US ⏱️ 0.0 years remaining

Composite function element and process for producing the same

Assignee: Panasonic Holdings Corp
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Filing: 1981-05-21
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Granted: 1984-10-02
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Expires: 2001-05-21
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Abstract

Abstract This invention relates to a composite function element which includes a high resistance thin film layer containing the constitutional elements of a perovskite type oxide and specified impurity elements at the grain boundary of a sintered body, said sintered body comprises an agglomerate of n type semiconductor particles and to a process for producing said composite function element. The composite function element has a composite function such that it acts as a varistor passing high voltages at a high voltage and as a capacitor passing the currents of abnormal frequency zone at a low voltage, so that the functions of two elements, a varistor and a capacitor, can be fulfilled simultaneously with only one element. Therefore, its extensive application in uses such as, for example, prevention of erroneous operation of microcomputer-controlled instruments can be expected.

Inventors

  • 👤 Gen Itakura
  • 👤 Yoshihiro Matsuo

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 09:43
CPC Classifications
H; H01; H01C; H01C7/00; H01C7/10; H01C7/105; H01C7/108; C; C04; C04B; C04B35/00; C04B35/01; C04B35/46; C04B35/462; C04B35/475

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 157 words
A composite function element, comprising: a sintered body having a grain boundary and at least first and second surfaces, said sintered body comprising an agglomerate of n-type semiconductor particles; a high resistance thin film layer provided at the grain boundary of the sintered body at one of said surfaces, said film layer including at least one element selected from the group consisting of barium, strontium, calcium and lead; at least one element selected from the group consisting of titanium, tin and zirconium; and at least one element selected from the group consisting of bismuth, boron, cerium, cobalt, copper, iron, lanthanum, lithium, manganese, niobium, antimony, silicon and zinc; and at least one pair of electrodes respectively provided on said surfaces of the sintered body, said composite function element being characterized in that it acts as a capacitor when lower voltage is passing between the electrodes and acts as a varistor when higher voltage is passing between the electrodes.
Claim 2
Dependent Claim 157 words
A composite function element, comprising: a sintered body having a grain boundary and at least first and second surfaces, said sintered body comprising an agglomerate of n-type semiconductor particles; a high resistance thin film layer provided at the grain boundary of the sintered body at one of said surfaces, said film layer including at least one element selected from the group consisting of barium, strontium, calcium and lead; at least one element selected from the group consisting of titanium, tin and zirconium; and at least one element selected from the group consisting of bismuth, boron, cerium, cobalt, copper, iron, lanthanum, lithium, manganese, niobium, antimony, silicon and zinc; and at least one pair of electrodes respectively provided on said surfaces of the sintered body, said composite function element being characterized in that it acts as a capacitor when lower voltage is passing between the electrodes and acts as a varistor when higher voltage is passing between the electrodes.
Claim 3
Dependent Claim 114 words
The composite function element according to claim 1, wherein the sintered body comprises an n-type sintered body containing strontium titanate as its principal component; and the high resistance thin film layer comprises a high resistance diffused layer provided at the grain boundary of the sintered body, said diffused layer comprising an agglomerate of perovskite type oxides including at least one element selected from the group consisting of barium, strontium, calcium and lead; at least one element selected from the group consisting of titanium, tin and zirconium; and at least one oxide of an element selected from the group consisting of bismuth, boron, cerium, cobalt, copper, iron, lanthanum, lithium, manganese, niobium, antimony, silicon and zinc.

References Cited (Backward Citations)

US3299332A Cited
US3386856A Cited
US3441517A Cited
US4131903A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-10-02 1988-04-02 1988-10-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-10-02 1992-04-02 1992-10-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-10-02 1996-04-02 1996-10-02 $7700.00 Window Closed / Lapsed

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