Resistor paste for printed circuits - based on semiconductive mixed cupric oxide/palladium oxide crystals

摘要

Mixed CuO/PdO crystals have much higher thermal stability than pure PdO (which is often used in resistor pastes): their resistance can be varied in a wide range (viz. from 0.1 to 4000 OMEGA cm) depending on the molar Pd:CuO ratio (from 6:1 to 1:3 resp). Apart from the CuO/PdO crystals, the paste contains a noble metal powder, a glaze component (pref. a lead borosilicate frit) and a combustible binder of the type used in the printed circuit technique (e.g. a soln. of ethyl cellulose in butyl glycol). After the screen printing on a ceramic substrate (e.g. alumina) the resistor pattern is fired at 850-900 degrees C.