To reduce the number of part items, make a sensor thin, miniaturize it, and improve noise resistance by forming an opened recess on a box-like molded base, forming a conductive thin film having a prescribed pattern on the surface of the base including its inner face, connecting a sensor element to the recess, and sealing the molded base with a cover.
A resin such as epoxy is injection-molded to form a molded base 2, irregularities are generated on the whole surface with a strong alkaline solution, then the base 2 is nucleated with palladium, and a metal conductive thin film is formed on the whole face of the base 2. Photosensitive resist is formed on the film, the photosensitive resist is removed to expose a metal conductive film layer at the portion for a pattern, and the portion is used as a cathode to complete a microwave circuit 3. One end of an acceleration sensor element 4 made of a ceramic piezoelectric element is inserted and supported into the support section 6 of the base 2. A conductive adhesive is filled and hardened into the end section 1a of a recess 1 to connect the electrode of the element 4 and the electrode of the base 2. A cover 5 made of a printed board and the base 2 supporting the sensor element 4 are connected by a nonconductive adhesive.
MATSUYAMA JUN
OOTANI RIYUUJI
MUTO MASAHIDE
NAKAMURA YOSHIMITSU
MORI HIDEO
KOBAYASHI YOSHINOBU
