PURPOSE: To improve the solder wettability and bonding strength of a circuit substrate by not containing glass as an inorganic binder in a conductor composition when the substrate is covered with the composition.

CONSTITUTION: The composition indispensably contains silver powder and palladium powder divided finely, and additionally contains both or one of rhodium powder and organic rhodium compound in a dispersive state in vehicle. Arbitrary one containing no glass component, e.g., a binder containing as main ingredient bismuth oxide of inorganic binder is used. In this case, metallic powder and, as required, inorganic binder are dispersed in a vehicle, a glass or a glass ceramic substrate is coated therewith, seized at 750∼900°C, preferably approx. 850°C for 5∼30 min to obtain a circuit substrate covered with conductor composition.