PURPOSE: To attain to miniaturize a double-surface type humidity-sensitive element, by respectively mounting comb-shaped electrode layers and humidity-sensitive layers applied to said electrode layers to both sides of a ceramic substrate.
CONSTITUTION: Comb shaped electrode layers 12 are formed to both surfaces of a ceramic substrate by a method wherein nickel is vapor deposited to each surface of the substrate to form an under electrode and gold or platinum is subsequently vapor deposited thereon to form a rust-proof upper electrode. After the electrode layers are formed, coating layers 14 each comprising a humidity-sensitive material are formed to the electrode layers 12. The humidity-sensitive material is applied to each electrode layer in a thickness of about 20μm by screen printing and, thereafter, baked at 130W190°C for several ten min. Because the electrode layers and the humidity-sensitive material layers are formed to both front and back surfaces of the substrate, a highly sensitive humidity-sensitive element reduced in a substrate area to a large extent is obtained.
KIUCHI NORIHIRO
TOMINAGA TSUTOMU
TOYAMA PREFECTURE