PURPOSE: To obtain an electronic circuit device having an extra-fine thick film circuit pattern having a sufficiently large film thickness by a method wherein the thick film conductor wiring is composed of a baked film which is made of material whose component is metal powder containing inorganic binder and has a line width not larger than 80μm and a film thickness not smaller than 15μm.
CONSTITUTION: A thick film conductor wiring is composed of a baked film which is made of material whose main component is metal powder containing inorganic binder and has line width not larger than 80μm and a film thickness not smaller than 5μm. The thick film circuit which is baked on a ceramic substrate is made of paste composition containing conductive solid particles such as copper powder whose particle size distribution is so controlled as to have the particle diameters within a preferable range to suppress the shrinkage of the film thickness caused by baking. With this constitution, the reduction of the thickness of the circuit film formed on the ceramic substrate can be suppressed and, especially, an extra-fine low impedance electronic circuit pattern having a line width not larger than 80μm can be obtained.
ASAI TADAMICHI
ITO OSAMU
KAMIMURA NORITAKA
OGIWARA SATORU
KOBAYASHI TAKAO
ISOMAE HIROMI
ISHIDA YOSHIKATSU
OTANI MICHIO
EBISAWA KATSUO
HITACHI CHEMICAL CO LTD