Patent ID: 7329975

Claim:
An ultrasonic sensor comprising: a housing member having a sensor substrate and a frame member; a semiconductor substrate housed in the housing member; a plurality of conversion means formed on a surface of the semiconductor substrate for converting one of a received ultrasonic wave into an electric signal and an electric signal into an ultrasonic wave for transmission, the plurality of conversion means being juxtaposed, wherein each of the conversion means has a sensing element sandwiched between two electrode layers; protection means for protecting each of the conversion means, the protection means including a protective film provided at a first side of the conversion means, and a first gap defined between the protective film and the conversion means, the first gap being filled with one of a liquid, a sol and a gel; a second gap formed between a second side of the conversion means and the sensor substrate; and a plurality of bumps arranged in the second gap so as to electrically connect both of the electrode layers of the sensing element to corresponding wiring layers formed on the surface of the sensor substrate.