Heraeus Electro-nite International N.v.

Heraeus Sensor Technology Gmbh

Heracus Sensor Technology Gmbh

Heraeus Nexensos Gmbh

Margit Sander

Karlheinz Wienand

Stefan Dietmann

Karlheinz Ullrich

Matsvei Zinkevich

Thomas Loose

Christian Baerts

Werner Englert, Deceased

The invention relates to temperature sensors, in particular high-temperature sensors, having an optionally coated substrate, at least one resistor structure, and at least two connection contacts. The connection contacts electrically contact the resistor structure, and the substrate is made of zirconium oxide or a zirconium oxide ceramic stabilized with oxides of a trivalent metal and a pentavalent metal. The substrate is coated with an insulation layer and the resistor structure and the free regions of the insulation layer, on which no resistor structure is disposed, are at least partially coated with a ceramic intermediate layer. A protective layer and/or a cover is disposed on the ceramic intermediate layer. At least one electrode may be disposed, at least at one connection contact, alongside the resistor structure on the substrate. The invention also relates an exhaust-gas system for controlling and/or regulating an engine, particularly a motor vehicle engine, containing these temperature sensors.

High-temperature chip with high stability

A high temperature sensor includes a substrate, at least two terminal contacts and at least one resistive structure, wherein the terminal contacts and the at least one resistive structure are disposed on a first side of the substrate, and at least one of the resistive structures is electrically contacted by the terminal contacts, wherein at least one electrode is disposed on each of the two terminal contacts next to the resistive structure on the first side of the substrate. The electrodes are electrically connected to the terminal contacts, respectively, or at least one electrode is disposed on at least one terminal contact next to the resistive structure on the first side of the substrate, wherein the electrode is designed in one piece with the resistive structure. The invention also relates to a high temperature sensor and a method for producing such a sensor.

Measuring shunt comprising protective frame

For production of a high-temperature sensor, in which a platinum resistance film is applied on a metal-oxide substrate, in particular sapphire or a ceramic plate, and a ceramic intermediate layer is laid on the resistance film, a self-supporting cover, in particular a ceramic or glass-ceramic cover, is bonded on the ceramic intermediate layer or a glass ceramic is mounted on the intermediate layer over its entire surface. Advantageously, the glass ceramic is electrically conductive or an ion conductor above 750&#xb0; C. and is laid on up to the cathode of the resistance film up to beyond the intermediate layer. In particular, the cover is bonded with a metal-doped glass ceramic, which is laid on the cathode of the resistance film up to beyond the intermediate layer. Preferably, the electrically insulating intermediate layer is coated with a glass ceramic or a glass ceramic doped with metal, which coating has a resistance of at most one megaohm per square at 850&#xb0; C. or above.

1200&#xb0; C. film resistor

An electrical temperature sensor has a platinum-containing resistance layer as a measuring resistor, which is applied on the electrically insulating surface of a ceramic substrate. For protection against contamination or damage, the resistance layer is provided on its side facing away from the ceramic substrate with an intermediate layer as a diffusion barrier layer. In a first embodiment, a platinum layer as an electrode is applied on the intermediate layer spaced from the resistance layer. The electrode protects the measuring resistance against platinum poisons, such as stray silicon ions, which could emerge, for example, from a passivation layer made of glass. In a second embodiment, the electrical temperature sensor is provided with a multiple layer, wherein a covering layer is applied on the intermediate layer as a passivation layer made of glass. Also in this embodiment, an electrode in the form of a platinum layer can be applied spaced from the resistance layer. The intermediate layer functioning as a diffusion barrier layer is made of a ceramic containing Al O , MgO or tantalum oxide. Furthermore, it is also possible to insert an intermediate layer made of a layer system with a series of layers of several oxides.

Electrical temperature sensor having one or more layers

A process is provided for manufacturing a sensor arrangement for temperature measurement with a temperature-sensitive measuring resistance which has a thin, metal resistance layer electrically insulated toward the outside, and exposed contact surfaces on a ceramic substrate. The contact surfaces are connected electrically conducting and directly mechanically fast with high temperature-resistant conductor paths electrically insulated from one another on a ceramic carrier element. The measuring resistance is bonded and attached by application to and subsequent firing on a carrier element prepared prior to outfitting. A platinum-containing thick film conducting paste serves as a means for attachment and bonding. Contact surfaces for connecting a plug or cable are arranged at the end of the carrier element facing away from the measuring resistance. The temperature sensor, a standard component in the form of a flat measuring resistance, is applied to the ceramic carrier element without the use of wires as an SMD component. The sensor arrangement manufactured by the process is suited for temperature measurements even above 400&deg; C. The process is economical in that it uses a few standardized individual component parts and easily automatable operation steps.

Process for manufacturing a sensor arrangement for temperature measurement

A temperature-dependent measuring resistance with rapid response time is at least partially arranged on an electrically insulating surface of a ceramic substrate, wherein a portion of the conductor path spans a recess situated in the substrate in a bridge-like manner, and the remaining portion of the conductor path in the edge area of the substrate adjacent to the recess is provided with connection contact fields. The conductor path comprises a platinum or gold layer, wherein the conductor path is partially provided with a cover layer of glass, and wherein the connection contact fields are exposed. In a further embodiment, the conductor path is arranged together with the connection contact fields either on a screen-printed glass membrane or on a thin film membrane applied in a PVD process, which covers the surface of the ceramic substrate and spans the recess. The cover layer is likewise selectively applied by screen printing in case there is a glass membrane. In the case of a thin film membrane, the cover layer is also applied selectively by a PVD process and can be the same material as the thin film membrane. The ceramic substrate preferably comprises aluminum oxide.

Electrical resistance with at least two contact fields on a ceramic

In a temperature sensor with a platinum resistance thermometer accommodated in a tube-shaped housing, the platinum resistance layer belonging thereto should be protected against pollution or contamination of the platinum, since the electrochemical characteristics of platinum can be reduced by substances in the surroundings in the event of too low a partial pressure of oxygen. For this purpose, a mechanically solid and liquid-impermeable, connection is provided in the connection region of the tube-shaped housing, which permits an admission of air-oxygen into the housing from the environment of the connecting cable. The air-oxygen admission is made possible through a liquid-impermeable oxygen-permeable jacket for the connecting cable and/or over an accompanying connecting plug, whereby the admission of air-oxygen takes place along a glass filament filler running parallel to the electrical leads inside the jacket of the connecting cable.

Growing community of inventors

Karlstein, Germany

Margit Sander