EP0065806A2 - Résistance dépendant de la tension et procédé pour sa fabrication - Google Patents

Résistance dépendant de la tension et procédé pour sa fabrication Download PDF

Info

Publication number: EP0065806A2
Authority: EP; European Patent Office
Prior art keywords: metal oxide; sintered body; metal; voltage; dependent resistor
Prior art date: 1981-05-29
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.): Granted

Application number

EP82200615A

Other languages

German (de)

English (en)

Other versions

EP0065806A3 (en

EP0065806B1 (fr

Inventor

Detlev Dr. Hennings

Axel Dr. Schnell

Herbert Schreinemacher

Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)

Philips Intellectual Property and Standards GmbH

Koninklijke Philips NV

Original Assignee

Philips Patentverwaltung GmbH

Philips Gloeilampenfabrieken NV

Koninklijke Philips Electronics NV

Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)

1981-05-29

Filing date

1982-05-19

Publication date

1982-12-01

1982-05-19 Application filed by Philips Patentverwaltung GmbH, Philips Gloeilampenfabrieken NV, Koninklijke Philips Electronics NV filed Critical Philips Patentverwaltung GmbH

1982-12-01 Publication of EP0065806A2 publication Critical patent/EP0065806A2/fr

1983-05-04 Publication of EP0065806A3 publication Critical patent/EP0065806A3/de

1985-11-21 Application granted granted Critical

1985-11-21 Publication of EP0065806B1 publication Critical patent/EP0065806B1/fr

Status Expired legal-status Critical Current

Links

230000001419 dependent effect Effects 0.000 title claims abstract description 25
238000004519 manufacturing process Methods 0.000 title claims description 9
229910044991 metal oxide Inorganic materials 0.000 claims abstract description 54
150000004706 metal oxides Chemical class 0.000 claims abstract description 34
-1 alkaline earth metal titanate Chemical class 0.000 claims abstract description 32
230000008018 melting Effects 0.000 claims abstract description 18
238000002844 melting Methods 0.000 claims abstract description 18
229910052751 metal Inorganic materials 0.000 claims abstract description 13
239000002184 metal Substances 0.000 claims abstract description 13
239000000725 suspension Substances 0.000 claims abstract description 13
229910052784 alkaline earth metal Inorganic materials 0.000 claims abstract description 12
239000000919 ceramic Substances 0.000 claims abstract description 12
238000009792 diffusion process Methods 0.000 claims abstract description 7
229910052761 rare earth metal Inorganic materials 0.000 claims abstract description 6
230000001590 oxidative effect Effects 0.000 claims abstract description 5
150000002910 rare earth metals Chemical group 0.000 claims abstract description 5
150000001342 alkaline earth metals Chemical class 0.000 claims abstract 3
238000005245 sintering Methods 0.000 claims description 17
238000000034 method Methods 0.000 claims description 13
239000000463 material Substances 0.000 claims description 8
239000000203 mixture Substances 0.000 claims description 7
239000011230 binding agent Substances 0.000 claims description 6
XKENYNILAAWPFQ-UHFFFAOYSA-N dioxido(oxo)germane;lead(2+) Chemical compound [Pb+2].[O-][Ge]([O-])=O XKENYNILAAWPFQ-UHFFFAOYSA-N 0.000 claims description 6
238000000227 grinding Methods 0.000 claims description 5
229920006395 saturated elastomer Polymers 0.000 claims description 5
150000002739 metals Chemical class 0.000 claims description 3
229920002689 polyvinyl acetate Polymers 0.000 claims description 3
239000011118 polyvinyl acetate Substances 0.000 claims description 3
XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 3
239000004372 Polyvinyl alcohol Substances 0.000 claims description 2
229920002451 polyvinyl alcohol Polymers 0.000 claims description 2
230000002441 reversible effect Effects 0.000 claims description 2
229910052712 strontium Inorganic materials 0.000 claims description 2
239000000126 substance Substances 0.000 claims description 2
FGUUSXIOTUKUDN-IBGZPJMESA-N C1(=CC=CC=C1)N1C2=C(NC([C@H](C1)NC=1OC(=NN=1)C1=CC=CC=C1)=O)C=CC=C2 Chemical compound C1(=CC=CC=C1)N1C2=C(NC([C@H](C1)NC=1OC(=NN=1)C1=CC=CC=C1)=O)C=CC=C2 FGUUSXIOTUKUDN-IBGZPJMESA-N 0.000 claims 3
GNFTZDOKVXKIBK-UHFFFAOYSA-N 3-(2-methoxyethoxy)benzohydrazide Chemical compound COCCOC1=CC=CC(C(=O)NN)=C1 GNFTZDOKVXKIBK-UHFFFAOYSA-N 0.000 claims 1
239000000470 constituent Substances 0.000 claims 1
229910052746 lanthanum Inorganic materials 0.000 claims 1
FZLIPJUXYLNCLC-UHFFFAOYSA-N lanthanum atom Chemical compound [La] FZLIPJUXYLNCLC-UHFFFAOYSA-N 0.000 claims 1
239000000155 melt Substances 0.000 claims 1
239000010955 niobium Substances 0.000 claims 1
229910052758 niobium Inorganic materials 0.000 claims 1
GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 claims 1
238000003825 pressing Methods 0.000 claims 1
CIOAGBVUUVVLOB-UHFFFAOYSA-N strontium atom Chemical compound [Sr] CIOAGBVUUVVLOB-UHFFFAOYSA-N 0.000 claims 1
WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 claims 1
229910052721 tungsten Inorganic materials 0.000 claims 1
239000010937 tungsten Substances 0.000 claims 1
239000010410 layer Substances 0.000 description 10
238000000137 annealing Methods 0.000 description 6
150000002500 ions Chemical class 0.000 description 6
229910010413 TiO 2 Inorganic materials 0.000 description 5
239000007789 gas Substances 0.000 description 5
230000007423 decrease Effects 0.000 description 3
238000010438 heat treatment Methods 0.000 description 3
238000005496 tempering Methods 0.000 description 3
238000012360 testing method Methods 0.000 description 3
VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
238000011161 development Methods 0.000 description 2
239000002019 doping agent Substances 0.000 description 2
238000002474 experimental method Methods 0.000 description 2
239000007788 liquid Substances 0.000 description 2
239000000843 powder Substances 0.000 description 2
239000004065 semiconductor Substances 0.000 description 2
239000007858 starting material Substances 0.000 description 2
229910015902 Bi 2 O 3 Inorganic materials 0.000 description 1
229910002367 SrTiO Inorganic materials 0.000 description 1
229910010252 TiO3 Inorganic materials 0.000 description 1
239000012790 adhesive layer Substances 0.000 description 1
QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
230000015572 biosynthetic process Effects 0.000 description 1
238000012512 characterization method Methods 0.000 description 1
230000000694 effects Effects 0.000 description 1
230000005496 eutectics Effects 0.000 description 1
PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
239000010931 gold Substances 0.000 description 1
229910052737 gold Inorganic materials 0.000 description 1
239000008187 granular material Substances 0.000 description 1
238000005259 measurement Methods 0.000 description 1
229910052760 oxygen Inorganic materials 0.000 description 1
239000001301 oxygen Substances 0.000 description 1
239000002994 raw material Substances 0.000 description 1
238000000926 separation method Methods 0.000 description 1
VEALVRVVWBQVSL-UHFFFAOYSA-N strontium titanate Chemical compound [Sr+2].[O-][Ti]([O-])=O VEALVRVVWBQVSL-UHFFFAOYSA-N 0.000 description 1
230000009897 systematic effect Effects 0.000 description 1
238000007740 vapor deposition Methods 0.000 description 1
238000005303 weighing Methods 0.000 description 1

Images

Classifications

- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01C—RESISTORS
- H01C7/00—Non-adjustable resistors formed as one or more layers or coatings; Non-adjustable resistors made from powdered conducting material or powdered semi-conducting material with or without insulating material
- H01C7/10—Non-adjustable resistors formed as one or more layers or coatings; Non-adjustable resistors made from powdered conducting material or powdered semi-conducting material with or without insulating material voltage responsive, i.e. varistors
- H01C7/105—Varistor cores
- H01C7/108—Metal oxide
- H01C7/115—Titanium dioxide- or titanate type

Definitions

the invention relates to a voltage-dependent resistor with a ceramic sintered body based on a polycrystalline alkaline earth metal titanate doped with a small amount of a metal oxide to produce an N-type conductivity, with electrodes arranged on opposite surfaces, and a method for producing such a resistor.
a voltage-dependent resistor is known from German patent application P 30 19 969.0, which is based on N-doped strontium titanate, to which a small proportion of a lead germanate phase was added before sintering, which leads to the formation of insulating grain boundary layers in the polycrystalline structure of the sintered body.
This known resistor can only be used to a limited extent because of its relatively high field strength - a current density of, for example, about 3 mA / cm 2 only occurs in fields of about 6 K V / cm; for example, it is not suitable for modern semiconductor circuits that operate at low voltages.
the invention has for its object to provide a voltage-dependent resistor according to the preamble of the claim and a method for its production such that a voltage-dependent resistor with a low field strength is obtained.
a method for producing a voltage-dependent resistor with a ceramic sintered body based on a polycrystalline, alkaline earth metal titanate doped with a small amount of a metal oxide to produce an N-type conductivity is characterized in that the sintered body is first produced in a reducing atmosphere, and then this sintered body covered on its surface with a suspension containing at least one metal oxide which has a relatively low melting point in relation to the sintered body or at least one suspension containing metal oxide compound which has a relatively low melting point in relation to the sintered body and then in an oxidizing atmosphere, preferably in air, at a temperature above is the melting point of the suspension component (s) is annealed.
the insulating layers are formed from at least one metal oxide or at least one metal oxide compound which (has) a lower melting point than the PerowsKit phase, (which) wets the polyCrystalline PerowsKit phase well at their grain edge regions and which (the) field strengths occurring during operation of the component shows reversible breakthrough signs. Due to the simultaneous presence of these parameters, good varistor properties are obtained due to influences at the grain boundaries.
the alkaline earth metal titanate is reacted by reacting S r C 0 3 with Ti0 2 in a molar ratio of 1: 1.001 to 1: 1.02 with the addition of the doping metals in the form of their oxides in an amount of 0.05 to a maximum 60 mol% of the component to be substituted formed after grinding and presintering for 15 h at 1150 ° C in air.
this is, according to a further advantageous embodiment of the invention, 4 hours at a temperature of 1460 ° C. in a reducing atmosphere consisting of mixed gas saturated with water vapor from 90 vol. % N 2 and 10 vol.% H 2 sintered.
La doped metal oxide La203, Nb 2 0 5 or W0 3 and metal oxide Bi 2 0 3 to be diffused in or metal oxide compound to be diffused in lead germanate Pb 5 Ge 3 0 11 are used.
La 3+ , Nb 5+ and W 6+ ions have proven to be particularly suitable for N doping.
dopants for example other rare earth metal ions such as Sm 3+ or else Y 3+ ; instead of Nb 5+ , Ta 5+ , As 5+ or Sb 5+ and instead of W 6+ , Mo 6+ and U 6+ can be used.
a suspension with at least one metal oxide with a relatively low melting point in relation to the sintering body or at least one metal oxide compound with a relatively low melting point with respect to the sintered body is applied to the sintered bodies 11 , applied in an organic binder and baked under oxidizing conditions at temperatures around or above 900 ° C., the applied, molten metal oxide or the metal oxide compound diffuses preferably along the grain boundaries in the semiconducting KeramiK and creates highly insulating grain boundary layers there.
Fig. 1 the current-voltage characteristic of a varistor of the composition Sr (Ti 0.996 W 0.004 ) is 0 3 . 0.01TiO 2 and a diffused phase of Pb 5 Ge 3 0 11 shown.
the varistor found is therefore characterized in comparison to the known varistor by a factor of> 10 lower field strength. This makes the varistor in use particularly suitable for modern semiconductor circuits that operate at low voltages. A comparable behavior can also be found in Nb- and La-doped SrTi0 3 varistors according to the invention.
the voltage across a varistor of composition is Sr (Ti 0.996 W 0.004 ) O 3 . 0.01TiO 2 with a diffused phase of Bi 2 0 3 at 1 mA and 30 mA depending on the temperature.
a liquid sintering phase with the SrTi0 3 is formed at a sintering above 1400 ° C - it can be assumed that this is the EuteKtiKum SrTiO 3 -TiO 2 occurring at ⁇ 1440 ° C, which is also due to the addition of dopants Can occur at lower temperatures.
a liquid sintering phase of this type promotes coarse grain growth, which, as already stated, is desirable.
the raw materials are weighed in an amount corresponding to the desired composition and 2 hours in one Ball mill, e.g. made of agate, wet mixed. This is followed by presintering at 1150 ° C for 15 h.
the presintered powders are wet-ground again (1 h in a ball mill, for example made of agate).
the ground material is then dried and the powders obtained in this way are then granulated using a suitable binder, for example a 10% aqueous polyvinyl alcohol solution.
the granules are pressed into shaped bodies suitable for ceramic resistances, e.g. into disks with a diameter of ⁇ 6 mm and a thickness of ⁇ 0.50 mm to a green density (bulk density) of approx.
the atmosphere can consist, for example, of mixed gas saturated with water vapor of 90 vol.% N 2 and 10 vol.% H 2 . Since the oxygen partial pressure of the mixed gas is determined by the ratio of the two partial pressures p H2 / P H2 0 ', the mixed gas was saturated with H 2 0 at ⁇ 25 ° C in order to create an always comparable reduction atmosphere.
sintering it is remarkable that coarse-grained structures preferably occur at sintering temperatures above 1440 ° C.
the reducing sintering should take place in a tightly closing furnace, for example a tube furnace is suitable. Excess reducing gas should flow out via a bubble counter in order to create a constant sintering atmosphere. Sintered bodies produced in this way are semiconducting and no longer show open porosity.
the insulating grain edge layers are made by diffusing in at least one molten metal oxide or at least one metal oxide compound, for example Bi 2 0 3 or lead germanate Pb 5 Ge 3 O 11 , is produced in air.
the metal oxide or the metal oxide compound is first suspended in a binder based on polyvinyl acetate and applied to the already sintered KeramiK.
the suspended metal oxide or the suspended metal oxide compound is then baked into the sintered body by a tempering process at a temperature at which they are in the molten state.
the minimum annealing temperature was a temperature slightly above the melting point of the metal oxide used or the used metal oxide compound determined.
the amounts of the metal oxides or metal oxide compounds diffused into the sintered body were determined in parallel experiments by weighing the sintered bodies before applying the suspension, after burning out the binder in air at 600 ° C. and after tempering.
Table 2 shows that changes in the annealing time and the tempering temperature have no systematic influence on the values for the threshold voltage and the current index.
Different operating voltages of the finished component can, however, be set by different thickness of the components.
the sintered bodies treated with a diffusion phase made of Bi 2 0 3 show the normal VDR dependency superimposed on a negative resistance range, i.e. the voltage across the component decreases with increasing current, which can be advantageous in certain applications, since this is practically a value for the Current index ß ⁇ 0 corresponds (reference is made to Fig. 2).
An overvoltage is thereby not only limited to a certain value, but additional energy is absorbed in the component as the current decreases as the current increases.
This property of the sintered bodies treated with Bi 2 0 3 is only partially caused by the heating and the associated decrease in resistance of the components. This is shown in FIG. 3, in which the voltage across the component was plotted at 1 mA and 30 mA as a function of the temperature. The 30 mA values were measured by short current pulses, so that self-heating by the measuring current is negligible.

Landscapes

Engineering & Computer Science (AREA)
Microelectronics & Electronic Packaging (AREA)
Physics & Mathematics (AREA)
Electromagnetism (AREA)
Compositions Of Oxide Ceramics (AREA)
Thermistors And Varistors (AREA)

EP82200615A 1981-05-29 1982-05-19 Résistance dépendant de la tension et procédé pour sa fabrication Expired EP0065806B1 (fr)

Applications Claiming Priority (2)

Application Number	Priority Date	Filing Date	Title
DE3121289		1981-05-29
DE19813121289 DE3121289A1 (de)	1981-05-29	1981-05-29	Spannungsabhaengiger widerstand und verfahren zu seiner herstellung

Publications (3)

Publication Number	Publication Date
EP0065806A2 true EP0065806A2 (fr)	1982-12-01
EP0065806A3 EP0065806A3 (en)	1983-05-04
EP0065806B1 EP0065806B1 (fr)	1985-11-21

Family

ID=6133437

Family Applications (1)

Application Number	Title	Priority Date	Filing Date
EP82200615A Expired EP0065806B1 (fr)	1981-05-29	1982-05-19	Résistance dépendant de la tension et procédé pour sa fabrication

Country Status (4)

Country	Link
US (2)	US4581159A (fr)
EP (1)	EP0065806B1 (fr)
JP (1)	JPS57199202A (fr)
DE (2)	DE3121289A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number	Priority date	Publication date	Assignee	Title
US4612140A (en) *	1983-04-08	1986-09-16	Murata Manufacturing Co., Ltd.	Non-linear electrical resistor having varistor characteristics
WO2008107353A1 (fr) *	2007-03-02	2008-09-12	Epcos Ag	Matériau piézoélectrique, actionneur multicouches et procédé de fabrication d'un composant piézoélectrique

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number	Priority date	Publication date	Assignee	Title
DE3523681A1 (de) *	1985-07-03	1987-01-08	Philips Patentverwaltung	Verfahren zur herstellung keramischer sinterkoerper
JPH0670884B2 (ja) *	1986-12-27	1994-09-07	株式会社住友金属セラミックス	マイクロ波用誘電体磁器組成物
US5225126A (en) *	1991-10-03	1993-07-06	Alfred University	Piezoresistive sensor
DE10026258B4 (de) *	2000-05-26	2004-03-25	Epcos Ag	Keramisches Material, keramisches Bauelement mit dem keramischen Material und Verwendung des keramischen Bauelements
DE102009058795A1 (de) *	2009-12-18	2011-06-22	Epcos Ag, 81669	Piezoelektrisches Keramikmaterial, Verfahren zur Herstellung des piezoelektrischen Keramikmaterials, piezoelektrisches Vielschichtbauelement und Verfahren zur Herstellung des piezoelektrischen Vielschichtbauelements
CN111542900B (zh)	2017-12-01	2022-04-15	京瓷Avx元器件公司	低纵横比压敏电阻

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number	Priority date	Publication date	Assignee	Title
DE1303160C2 (de) *	1963-12-13	1974-06-12	Philips Nv	Verfahren zur herstellung eines durch fremdionen halbleitend gemachten elektrischen sperrschichtkondensators
US3561106A (en) *	1968-07-03	1971-02-09	Univ Iowa State Res Found Inc	Barrier layer circuit element and method of forming
US3933668A (en) *	1973-07-16	1976-01-20	Sony Corporation	Intergranular insulation type polycrystalline ceramic semiconductive composition
GB1556638A (en) *	1977-02-09	1979-11-28	Matsushita Electric Industrial Co Ltd	Method for manufacturing a ceramic electronic component
US4237084A (en) *	1979-03-26	1980-12-02	University Of Illinois Foundation	Method of producing internal boundary layer ceramic compositions
JPS56169316A (en) *	1980-05-30	1981-12-26	Matsushita Electric Industrial Co Ltd	Composition functional element and method of producing same
JPS5735303A (en) *	1980-07-30	1982-02-25	Taiyo Yuden Kk	Voltage vs current characteristic nonlinear semiconductor porcelain composition and method of producing same
US4347167A (en) *	1980-10-01	1982-08-31	University Of Illinois Foundation	Fine-grain semiconducting ceramic compositions
US4419310A (en) *	1981-05-06	1983-12-06	Sprague Electric Company	SrTiO3 barrier layer capacitor
JPS58103116A (ja) *	1981-12-16	1983-06-20	太陽誘電株式会社	コンデンサ用半導体磁器
JPS5891602A (ja) *	1981-11-26	1983-05-31	太陽誘電株式会社	電圧非直線磁器組成物
US4436650A (en) *	1982-07-14	1984-03-13	Gte Laboratories Incorporated	Low voltage ceramic varistor

1981
- 1981-05-29 DE DE19813121289 patent/DE3121289A1/de not_active Withdrawn
1982
- 1982-05-19 DE DE8282200615T patent/DE3267542D1/de not_active Expired
- 1982-05-19 EP EP82200615A patent/EP0065806B1/fr not_active Expired
- 1982-05-28 US US06/382,910 patent/US4581159A/en not_active Expired - Fee Related
- 1982-05-28 JP JP57090029A patent/JPS57199202A/ja active Granted
1985
- 1985-07-11 US US06/753,757 patent/US4692289A/en not_active Expired - Fee Related

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number	Priority date	Publication date	Assignee	Title
US4612140A (en) *	1983-04-08	1986-09-16	Murata Manufacturing Co., Ltd.	Non-linear electrical resistor having varistor characteristics
WO2008107353A1 (fr) *	2007-03-02	2008-09-12	Epcos Ag	Matériau piézoélectrique, actionneur multicouches et procédé de fabrication d'un composant piézoélectrique
CN101627484B (zh) *	2007-03-02	2011-03-30	埃普科斯股份有限公司	压电材料、多层致动器以及用于制备压电构件的方法
US7999448B2 (en)	2007-03-02	2011-08-16	Epcos Ag	Piezoelectric material, multilayer actuator and method for manufacturing a piezoelectric component

Also Published As

Publication number	Publication date
JPH0236041B2 (fr)	1990-08-15
DE3267542D1 (en)	1986-01-02
US4581159A (en)	1986-04-08
EP0065806A3 (en)	1983-05-04
JPS57199202A (en)	1982-12-07
EP0065806B1 (fr)	1985-11-21
US4692289A (en)	1987-09-08
DE3121289A1 (de)	1982-12-23

Legal Events

Date	Code	Title	Description
1982-10-01	PUAI	Public reference made under article 153(3) epc to a published international application that has entered the european phase	Free format text: ORIGINAL CODE: 0009012
1982-12-01	17P	Request for examination filed	Effective date: 19820519
1982-12-01	AK	Designated contracting states	Designated state(s): BE DE FR GB NL
1983-03-02	PUAL	Search report despatched	Free format text: ORIGINAL CODE: 0009013
1983-05-04	AK	Designated contracting states	Designated state(s): BE DE FR GB NL
1985-09-20	GRAA	(expected) grant	Free format text: ORIGINAL CODE: 0009210
1985-11-21	AK	Designated contracting states	Designated state(s): BE DE FR GB NL
1986-01-02	REF	Corresponds to:	Ref document number: 3267542 Country of ref document: DE Date of ref document: 19860102
1986-02-07	ET	Fr: translation filed
1986-09-24	PLBE	No opposition filed within time limit	Free format text: ORIGINAL CODE: 0009261
1986-09-24	STAA	Information on the status of an ep patent application or granted ep patent	Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT
1986-11-12	26N	No opposition filed
1987-05-31	PGFP	Annual fee paid to national office [announced via postgrant information from national office to epo]	Ref country code: NL Payment date: 19870531 Year of fee payment: 6
1989-05-19	PG25	Lapsed in a contracting state [announced via postgrant information from national office to epo]	Ref country code: GB Effective date: 19890519
1989-05-31	PG25	Lapsed in a contracting state [announced via postgrant information from national office to epo]	Ref country code: BE Effective date: 19890531
1989-12-01	PG25	Lapsed in a contracting state [announced via postgrant information from national office to epo]	Ref country code: NL Effective date: 19891201
1990-01-16	NLV4	Nl: lapsed or anulled due to non-payment of the annual fee
1990-01-17	GBPC	Gb: european patent ceased through non-payment of renewal fee
1990-01-31	PG25	Lapsed in a contracting state [announced via postgrant information from national office to epo]	Ref country code: FR Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19900131
1990-03-30	REG	Reference to a national code	Ref country code: FR Ref legal event code: ST
1995-07-24	PGFP	Annual fee paid to national office [announced via postgrant information from national office to epo]	Ref country code: DE Payment date: 19950724 Year of fee payment: 14
1997-02-01	PG25	Lapsed in a contracting state [announced via postgrant information from national office to epo]	Ref country code: DE Effective date: 19970201

Publication	Publication Date	Title
EP0351004B1 (fr)	1993-10-06	Résistance non linéaire dépendent de la tension
DE69603390T2 (de)	1999-12-30	Zinkoxidkeramiken und Verfahren zu ihrer Herstellung
DE2308073B2 (de)	1976-09-02	Keramischer elektrischer widerstandskoerper mit positivem temperaturkoeffizienten des elektrischen widerstandswertes und verfahren zu seiner herstellung
DE3732054C2 (fr)	1992-07-02
EP0040881B1 (fr)	1986-03-26	Résistance dépendant de la tension et procédé pour la fabrication
DE2915409A1 (de)	1979-10-18	Keramisches dielektrikum mit hoher dielektrizitaetskonstante
EP0065806B1 (fr)	1985-11-21	Résistance dépendant de la tension et procédé pour sa fabrication
EP3504169A1 (fr)	2019-07-03	Matériau ceramique, composant et procédé de fabrication dudit composant
EP0066333B1 (fr)	1985-08-28	Résistance non-linéaire et procédé pour sa fabrication
DE69021809T2 (de)	1996-03-28	Verfahren zur herstellung keramischer kondensatoren mit varistor-kennzeichen.
DE1956817B2 (de)	1972-06-22	Mangan-modifizierte spannungsabhaengige zinkoxid-widerstandskeramikmasse
DE2914130C2 (fr)	1989-02-23
EP0106401A2 (fr)	1984-04-25	Céramique diélectrique à base de titanate de baryum contenant du bismuth
DE102008046858A1 (de)	2010-03-18	Keramikmaterial, Verfahren zur Herstellung eines Keramikmaterials, elektrokeramisches Bauelement umfassend das Keramikmaterial
DE102007012468A1 (de)	2008-09-18	Keramikmaterial und elektrokeramisches Bauelement mit dem Keramikmaterial
DE3018595C2 (de)	1983-11-03	Spannungsabhängiger Widerstand und Verfahren zu dessen Herstellung
DE3206502C2 (fr)	1989-11-09
DE102009023846A1 (de)	2010-08-05	Varistorkeramik, Vielschichtbauelement umfassend die Varistorkeramik, Herstellungsverfahren für die Varistorkeramik
DE2225431C2 (de)	1982-11-25	Metalloxid-Varistor mit einem Gehalt an ZnO
EP0357113B1 (fr)	1994-01-12	Procédé de production d'une résistance non linéaire dépendant de la tension
DE2525053C2 (de)	1984-09-20	Nichtlinearer Widerstandskörper aus Zinkoxid(Varistor)
DE2303333C2 (de)	1982-12-23	Metalloxid-Varistor mit einem Gehalt an ZnO
DE2503438C3 (de)	1978-01-26	Keramisches dielektrisches Material
DE3319979A1 (de)	1983-12-08	Verfahren zur herstellung eines halbleiter-keramikkoerpers mit positivem temperaturkoeffizienten
DE1961680B2 (de)	1975-08-21	Spannungsabhängiger Widerstand auf der Basis von Zinkoxid