EP1286934A2 - Composant ceramique et son utilisation - Google Patents

Composant ceramique et son utilisation

Info

Publication number
EP1286934A2
EP1286934A2 EP01953769A EP01953769A EP1286934A2 EP 1286934 A2 EP1286934 A2 EP 1286934A2 EP 01953769 A EP01953769 A EP 01953769A EP 01953769 A EP01953769 A EP 01953769A EP 1286934 A2 EP1286934 A2 EP 1286934A2
Authority
EP
European Patent Office
Prior art keywords
ceramic
base body
ceramic component
contact layer
component according
Prior art date
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.)
Withdrawn
Application number
EP01953769A
Other languages
German (de)
English (en)
Inventor
Hermann GRÜNBICHLER
Peter Grobbauer
Adalbert Feltz
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.)
TDK Electronics AG
Original Assignee
Epcos AG
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.)
Filing date
Publication date
Application filed by Epcos AG filed Critical Epcos AG
Publication of EP1286934A2 publication Critical patent/EP1286934A2/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
    • C04B41/009—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone characterised by the material treated
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
    • C04B41/45—Coating or impregnating, e.g. injection in masonry, partial coating of green or fired ceramics, organic coating compositions for adhering together two concrete elements
    • C04B41/52—Multiple coating or impregnating multiple coating or impregnating with the same composition or with compositions only differing in the concentration of the constituents, is classified as single coating or impregnation
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
    • C04B41/80—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone of only ceramics
    • C04B41/81—Coating or impregnation
    • C04B41/89—Coating or impregnation for obtaining at least two superposed coatings having different compositions
    • 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
    • H01C7/02—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 having positive temperature coefficient
    • H01C7/022—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 having positive temperature coefficient mainly consisting of non-metallic substances
    • H01C7/023—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 having positive temperature coefficient mainly consisting of non-metallic substances containing oxides or oxidic compounds, e.g. ferrites
    • H01C7/025—Perovskites, e.g. titanates
    • 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
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
    • C04B2111/00474—Uses not provided for elsewhere in C04B2111/00
    • C04B2111/00844—Uses not provided for elsewhere in C04B2111/00 for electronic applications

Definitions

  • the invention relates to a ceramic component with a protective layer.
  • the invention relates to the use of the ceramic component.
  • Ceramic components are known which are used as varistors, which have high thermal stability and whose base body contains a mixture of metal oxides. Components of this type are usually soldered on boards in surface mounting and serve to protect the voltage of various electronic components in electrical devices and apparatuses of electrical engineering.
  • SMD capability surface mounting of the components is achieved by contacting the base body by baking a silver paste on the base body and then galvanizing the silver paste in one
  • Nickel and tin bath The outermost tin contact layer guarantees the SMD capability.
  • the contact layers are applied in the acid baths known from standard electroplating, which attack the ceramic component chemically.
  • a protective layer prevents acid attack on parts of the surface of the ceramic component that are not to be coated with the contact layer.
  • the known ceramic materials have the disadvantage that they have a high lead content.
  • the lead can easily penetrate into the interior of the ceramic base body and adversely affect the electrical characteristics of the ceramic component.
  • the non-environmentally friendly and toxic lead accumulates in the sintering furnace necessary for the production of ceramic components.
  • the aim of the present invention is therefore a ceramic
  • the invention provides a ceramic component with a
  • the specified ceramic materials can optionally contain other conventional constituents in small amounts that do not impair the desired properties.
  • the ceramic materials mentioned here represent modifications of the known PZT, PLZT and PLZST ceramics. They are characterized in that the lead from the known ceramics is at least partially replaced by bismuth. As a result, the ceramic materials have the advantage that they have a low lead content. Furthermore, the ceramic materials have the advantage that they are chemically resistant to the acid baths used in standard electroplating.
  • the ceramics mentioned are further characterized in that the entire lead content is not replaced by bismuth, but that cation gaps remain in the perovskite structure.
  • ⁇ formally marks a blank.
  • the modified formula (t ⁇ 1, v> 0) corresponding to the PLZST ceramic is: (Pb / La) 1 _ 3x Bi 2x ⁇ x (Zr, Sn, Ti) 0 3 .
  • the amount of materials contains a ceramic material with the general formula:
  • Bi / Ba a / b, where n is an integer and where: a) 1 ⁇ n ⁇ 5 b) 0 ⁇ b and a / b> 0.5.
  • the ceramic materials specified here can optionally contain other conventional constituents in small amounts, which do not impair the desired properties.
  • Ceramic materials have the advantage that they contain no lead and that they are chemically resistant to the acid baths used in the electroplating process.
  • the amount of materials contains a ceramic material with a pyrochlore structure, which can contain a rare earth metal SE, with the general formula: Bi 2 - Z SE Z (TijL_ x _y, Zr x , Sny) 2 ° 7 , where applies: O ⁇ z ⁇ l, O ⁇ x ⁇ l; O ⁇ y ⁇ l.
  • the specified ceramic materials can optionally contain other conventional constituents in small amounts that do not impair the desired properties.
  • Ceramic materials have the advantage that, owing to their resistance to the acid baths used in electroplating, they are suitable as a protective layer for ceramic components and that they contain no lead.
  • Such materials with a pyrochlore structure would be, for example
  • SE stands for an element of rare earths (e.g. lanthanum, praseodymium, samarium, gadolinium).
  • the ceramic component according to the invention has the advantage that, because of the protective layer, the ceramic base body is not chemically attacked by the galvanic application of the contact layer.
  • the ceramic component has the advantage that the electrical properties of the ceramic due to the low lead content of the protective layer
  • the ceramic component can not be changed by lead penetrating into the ceramic base body. Furthermore, the ceramic component has the advantage that, due to the low lead content of its protective layer, it is particularly environmentally friendly and less toxic.
  • a ceramic component is particularly advantageous in which there is a starting layer for the electroplating process between the base body and the contact layer.
  • the starting layer for the electroplating process has the advantage that the electroplating takes place in a clearly limited space, since the metal in the electroplating process only layer and does not deposit on the remaining surface of the base body.
  • the starting layer has the advantage that, because of its good electrical conductivity, which is necessary for the electroplating, it ensures good contacting of the ceramic base body of the component.
  • a ceramic component is particularly advantageous in which the contact layer is suitable for surface mounting the component. Due to the suitability of the contact layer for surface mounting (SMD capability), the entire component is suitable for surface mounting. With the help of surface mounting, a highly rationalized, automated assembly process of the components on a printed circuit board is possible.
  • a contact layer made of tin, for example, can be used as a particularly advantageous contact layer.
  • a ceramic component in which the starting layer is produced by a silver baking paste on the base body is particularly advantageous.
  • the silver baking paste has the advantage that it ensures good adhesion to the ceramic. This has a positive influence on the mechanical stability of the ceramic component.
  • a ceramic component is particularly advantageous, the base body of which has a contact layer on two opposite sides, which are contacted with electrically conductive electrodes located in the interior of the base body, the electrodes being arranged such that they measure the ohmic resistance measured between the contact layers reduce the component.
  • the electrodes in the interior of the base body have the advantage that they reduce the relatively high ohmic resistance of the ceramic to such an extent that the ceramic component has an electrical resistance which is adapted to the particular use of the component.
  • the ohmic resistance of the ceramic component can be flexibly adapted to the intended area of use of the component by suitable design of the conductive electrodes.
  • Palladium or silver is advantageously used as the material for the conductive electrodes. These two precious metals have the advantage that they can be sintered in air, which means that a special sintering atmosphere can be created.
  • the invention also provides a ceramic component in which the base body is a zinc oxide ceramic doped with aluminum, cobalt and manganese oxide.
  • a ceramic component has the advantage that it can be used as a varistor due to the special material properties of the base body.
  • Such components are important as voltage protection of electronic circuits on circuit boards in computer technology and communication technology as well as in electrical devices and apparatus of electrical engineering.
  • the SMD capability is an important prerequisite, so that the component according to the invention with its SMD capability, which is easy to obtain due to the protective layer, can be used particularly advantageously.
  • Figure 1 shows an example of a ceramic component according to the invention in a schematic perspective view.
  • FIG. 2 shows the ceramic component from FIG. 1 in a schematic longitudinal section.
  • FIG. 3 shows the area of the contact layer of the component from FIG. 2.
  • FIG. 1 shows a ceramic component according to the invention, which has a base body 1, on which a first contact layer 2 and a second contact layer 3 are arranged.
  • the two contact layers 2, 3 are galvanically applied tin layers. With the help of these tin layers, the component can be attached to a printed circuit board in SMD mounting.
  • FIG. 2 shows the ceramic component from FIG. 1 with a ceramic base body 1, which can be, for example, a doped zinc oxide ceramic.
  • a first contact layer 2 and a second contact layer 3 are applied to two opposite sides of the base body 1. These contact layers 2, 3 give the component its SMD capability.
  • a protective layer 4 made of one of the specified ceramic materials .
  • electrodes 6 which consist of a mixture of silver and palladium and which reduce the ohmic resistance of the component.
  • the component shown in FIG. 2 can be a varistor, which is manufactured according to the method described below:
  • the raw material mixture processed into a slip and processed into ceramic green foils.
  • Ceramic green foils are processed in a screen printing process using a precious metal paste suitable for sintering with the ceramic, with which the green foils are printed. This precious metal paste represents the electrodes 6.
  • the printed green foils are stacked, laminated and separated by cutting, from which green parts of a certain miniaturized design of multilayer varistors, essentially given by the geometric dimensions, result.
  • protective ceramic foils made of a ceramic material according to the invention are used as the base and cover foil, which have a high electrical resistance, are chemically stable with respect to the electroplating baths to be used later and are adapted in their sintering behavior to the varistor ceramic.
  • the green parts are printed on the respective cut sides with a screen printing paste consisting of the same passivating material.
  • a screen printing paste consisting of the same passivating material.
  • green parts are sintered and then provided with a metal paste consisting of silver or a silver-containing alloy on the end faces in the area of the emerging electrodes 6 in a dipping process.
  • the silver or the silver-containing alloy is then burned in in a separate process step, as a result of which contact is made with the electrodes 6 of the component.
  • This passivation layer also forms the starting layer 5 of the electroplating, which, as shown in FIG. 3, is located between the base body 1 and the second contact layer 3.
  • the baked metal paste is then electroplated with a nickel and tin layer to produce the contact layers 2, 3, as a result of which the component's SMD capability is established.
  • the passivation layers prevent the caustic partial dissolution of the varistor ceramic and, moreover, the deposition of nickel or tin on the ceramic surface between the end faces of the components.
  • a ceramic material according to the following formula: Big 4Pto 4 ⁇ 0 2 (T Zr 0 6 5 '- 0 3 5) ° 3 USAGE ⁇ be det.
  • the symbol ⁇ formally denotes an empty space.
  • Preparation technique mixed oxide technique with two conversions (once at 750 ° C and once at 950 ° C) followed by fine grinding.
  • Suitable raw materials for manufac Development of this compound are Bi 0 3 , Pb 3 0 4 , Zr0 2 and Ti0 2 .
  • the varistors are coated with the protective layer 4 before the components are sintered.
  • the coating itself can be carried out using conventional methods, for example by pasting the powder with an organic binding agent and solvent and then screen printing.
  • the protective layer 4 densifies to a large extent free of tension and pores, so that the surfaces printed with the protective layer 4 are sealed and protect against the acid attack of an electroplating bath.
  • the protective layer can fulfill its protective function, it must have a layer thickness between 20 and 50 ⁇ m.
  • the substances Bi 2 ZrTi ⁇ (bismuth zirconate / titanate) and Bi 2 SnTi ⁇ (bismuth stannate / titanate) are used.
  • This material can also be produced using the “mixed oxide” technique — similar to embodiment 1 — with conversion and subsequent fine grinding.
  • the protective layer 4 is again applied to the component by screen printing a paste.
  • protective layers 4 which are approximately twice as thick are required for these materials in order to prevent the acid attack of the electroplating. After sintering, voltage-free and dense protective layers 4 are formed, which do not have any influence on the electrical characteristics of the varistor.
  • the protective layer 4 according to exemplary embodiment 1 has somewhat better chemical stability compared to the acids used in electroplating than the protective layer 4 according to exemplary embodiment 2.
  • the influencing of the electrical characteristic values was again in the case of a ceramic material in accordance with exemplary embodiment 2, it was considerably cheaper than in the case of exemplary embodiment 1.
  • the evaporation of lead oxide was likewise substantially more favorable in the case of a ceramic material in accordance with exemplary embodiment 2. The reason for this is the obvious absolute freedom from lead of the protective layer 4 according to exemplary embodiment 2.
  • the invention is not limited to the exemplary embodiments shown, but is defined in its most general form by claim 1.

Abstract

La présente invention concerne un composant céramique comprenant une couche de protection (4) constituée de matériaux céramiques à faible teneur en plomb, se basant sur des structures perovskite, le plomb étant complètement ou partiellement remplacé par du bismuth. Sont également pris en considération, des titanates ayant une structure de phases du type Aurivillius, aucune teneur en plomb ne persistant. Sont également concernés, des composés ayant une structure pyrochlore et comprenant du bismuth et éventuellement un élément appartenant aux terres rares. Cette invention concerne également l'utilisation du composant céramique en tant que varistor. Le composant céramique présente des avantages en ce que, grâce à la couche de protection à faible teneur en plomb (4), les paramètres électriques du composant ne sont pas altérés, en ce que le composant peut être réalisé de manière écologique, et en ce que le composant résiste aux acides utilisés lors de l'application galvanique des couches de contact (possibilité CMS).
EP01953769A 2000-05-26 2001-05-25 Composant ceramique et son utilisation Withdrawn EP1286934A2 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE2000126258 DE10026258B4 (de) 2000-05-26 2000-05-26 Keramisches Material, keramisches Bauelement mit dem keramischen Material und Verwendung des keramischen Bauelements
DE10026258 2000-05-26
PCT/DE2001/002002 WO2001090026A2 (fr) 2000-05-26 2001-05-25 Composant ceramique et son utilisation

Publications (1)

Publication Number Publication Date
EP1286934A2 true EP1286934A2 (fr) 2003-03-05

Family

ID=7643743

Family Applications (1)

Application Number Title Priority Date Filing Date
EP01953769A Withdrawn EP1286934A2 (fr) 2000-05-26 2001-05-25 Composant ceramique et son utilisation

Country Status (4)

Country Link
EP (1) EP1286934A2 (fr)
AU (1) AU2001276258A1 (fr)
DE (1) DE10026258B4 (fr)
WO (1) WO2001090026A2 (fr)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102004045009B4 (de) * 2004-09-16 2008-03-27 Epcos Ag Elektrisches Bauelement und dessen Verwendung
DE102007020783A1 (de) 2007-05-03 2008-11-06 Epcos Ag Elektrisches Vielschichtbauelement
DE102007031510A1 (de) * 2007-07-06 2009-01-08 Epcos Ag Elektrisches Vielschichtbauelement
DE102015120640A1 (de) 2015-11-27 2017-06-01 Epcos Ag Vielschichtbauelement und Verfahren zur Herstellung eines Vielschichtbauelements
TWI605029B (zh) * 2016-10-12 2017-11-11 不含銻的壓敏電阻組成物及積層式壓敏電阻器
DE102020122299B3 (de) 2020-08-26 2022-02-03 Tdk Electronics Ag Vielschichtvaristor und Verfahren zur Herstellung eines Vielschichtvaristors
CN114716241B (zh) * 2021-12-29 2023-06-27 西南科技大学 一种高电压陶瓷介质材料及其制备方法与应用

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3121289A1 (de) * 1981-05-29 1982-12-23 Philips Patentverwaltung Gmbh, 2000 Hamburg Spannungsabhaengiger widerstand und verfahren zu seiner herstellung
DE3405834A1 (de) * 1984-02-17 1985-08-22 Siemens AG, 1000 Berlin und 8000 München Varistor aus einer scheibe aus durch dotierung halbleitendem zinkoxid-material und verfahren zur herstellung dieses varistors
DE3505862A1 (de) * 1985-02-20 1986-08-21 Siemens AG, 1000 Berlin und 8000 München Varistor und verfahren zu seiner herstellung
JP3113141B2 (ja) * 1993-12-28 2000-11-27 シャープ株式会社 強誘電体結晶薄膜被覆基板、その製造方法及び強誘電体結晶薄膜被覆基板を用いた強誘電体薄膜デバイス
DE19634498C2 (de) * 1996-08-26 1999-01-28 Siemens Matsushita Components Elektro-keramisches Bauelement und Verfahren zu seiner Herstellung
DE19653792A1 (de) * 1996-12-21 1998-06-25 Philips Patentverwaltung Bauteil mit flacher Temperaturcharakteristik

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO0190026A3 *

Also Published As

Publication number Publication date
DE10026258A1 (de) 2001-12-06
DE10026258B4 (de) 2004-03-25
WO2001090026A3 (fr) 2002-06-27
AU2001276258A1 (en) 2001-12-03
WO2001090026A2 (fr) 2001-11-29

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