Shoei Chemical Inc.

Toshio Inokuma

Eiichi Asada

Mikio Yamazoe

Hiroyuku Saito

Isao Egawa

A resistor composition comprising conductive particles, a glass frit and a vehicle in which RuO.sub.2 particles coated with a polynary oxide of Bi and/or Pb and Ru are employed and, by using the surface-coated RuO.sub.2, the composition can provide readily a improved resistor having a advantageous combination of properties, particularly a very small absolute TCR and high voltage stability throughout a wide resistance range. The produced resistor can be successfully laser-trimmed without adversely affecting the properties thereof.

Resistor compositions

Resistor compositions are disclosed which comprise: (a) ruthenium oxide; (b) glass; (c) at least one metal oxide selected from the group consisting of lanthanum oxide, neodymium oxide, praseodymium oxide and samarium oxide; and (d) an organic vehicle. Resistors are produced using this composition by firing a resistor film comprising ruthenium oxide, glass and at least one metal oxide selected from the group consisting of lanthanum oxide, neodymium oxide, praseodymium oxide and samarium oxide onto an electrically insulating substrate. The use of the metal oxides in the resistor compositions surprisingly improve the TCR (temperature coefficient of resistance) particularly in high resistance ranges, and brings the TCR close to zero. In addition to the effect of improving the TCR, the metal oxides increase resistance and improve noise and VCR (voltage coefficient of resistance) properties.

Resistor compositions and resistors produced therefrom

A thick film resistor comprising a resistive film element comprising 100 parts by weight of RuO.sub.2 and glass and 0.1 to 15 parts by weight of Au, electrodes containing not less than 50 weight percent of Ag therein connected to the terminal portions of the resistive film element, and an insulating substrate on which the resistive film element and the electrodes are formed.

Growing community of inventors

Fujisawa, Japan

Toshio Inokuma