Murata Manufacturing Co., Ltd.

Teppei Kubota

Hiroji Tani

Kazuto Miyagawa

Tohru Kasanami

A translucent ceramic contains a main component composed of a tungsten-bronze-type compound represented by a general formula {(Sr, Ba)NbO} (wherein v satisfies the relationship 1.8&#x2266;v&#x2266;2.2 and w represents a positive number for maintaining electrical neutrality), wherein some Nb atoms are replaced with atoms of at least one of Zn and Mg, and the replacement ratio is 0.004 or more in terms of the molar ratio. It is preferable that at least one of Sn and Bi is added in an amount of 0.15 parts by weight or more in terms of SnOand BiO, respectively, to 100 parts by weight of the main component, and that the molar ratio of Ba in the (Sr, Ba) site is in the range of 0.25 to 0.50. It is also preferable that the translucent ceramic contains Na in an amount of less than 25 parts by mole relative to 100 parts by mole of the sum of Sr and Ba, or La in an amount of less than 11 moles relative to 100 parts by mole of the sum of Sr and Ba. Accordingly, a translucent ceramic which is inexpensive and which is useful as an electro-optical material and an electro-optical component, such as an optical switch or an optical shutter, including the translucent ceramic can be realized.

Translucent ceramic and electro-optical component

A piezoelectric paste which is used for forming a piezoelectric thick film by the thick film forming technique, which can be burned at a relative low temperature and which can form a piezoelectric film having good polarizability and high piezoelectricity while maintaining the ferroelectricity possessed by a piezoelectric crystal powder contained in the piezoelectric paste contains the piezoelectric crystal powder containing a Pb(Zr, Ti)O system ceramic, a crystallized glass powder and an organic vehicle, wherein the crystallized glass powder used precipitates a Pb(Zr, Ti)O system solid solution phase by heat treatment.

Piezoelectric paste and piezoelectric film and piezoelectric part using the same

A platinum temperature sensor showing excellent sensitivity to heat. The sensor comprises an insulating substrate having a support portion at one end of the substrate. A heat-generating portion is formed by a platinum film circuit at the other end of the substrate. A coating made from a material having a low thermal conductivity is formed on the support portion of the insulating substrate to suppress dissipation of heat from the support portion. A first heat-insulating gap is created between an end portion of the platinum film circuit and the heat-generating portion. A second heat-insulating gap is created between the platinum film circuit and the coating.

Platinum temperature sensor

In order to improve uniformity of temperature distribution, despite heat which is generated in a resistance circuit and flows into a support part thereby causing a high output, a resistance circuit is provided with first, second and third regions having different resistance values so that the third region which is in proximity to the support part has the highest resistance value.

Resistance temperature sensor

A platinum temperature sensor includes a meandering pattern portion and outlet portions continuously connected to respective ends thereof which are defined by a platinum film which is formed on an insulating substrate. External electrodes are formed to cover the outlet portions as well as the ends of the insulating substrate provided with the outlet portions. Each of the external electrodes comprises a first layer containing platinum or nickel which is in contact with the outlet portion and with the insulating substrate, a second layer containing silver and platinum which is formed on the first layer, a third layer containing nickel which is formed on the second layer, and a fourth layer containing tin or solder which is formed on the third layer. The first layer suppresses diffusion of silver contained in the second layer, and the third layer improves heat resistance of the second layer, while the fourth layer improves solderability.

A method of manufacturing a platinum temperature sensor includes the step of obtaining a meandering resistive circuit by forming grooves in a platinum film which is provided on an insulating substrate. In order to provide a high resistance value by reducing the line width of the resistive circuit, as well as to miniaturize the platinum temperature sensor, this method comprises steps of forming a resist film on the platinum film provided on the insulating substrate, patterning the resist film by photolithography, and using the patterned resist film as a mask to finely work the platinum film by Ar.sup.+ ion etching for forming the grooves. Due to formation of such grooves, the platinum film defines a meandering pattern portion which provides the resistive circuit.

Growing community of inventors

Kyoto, Japan

Teppei Kubota