METHOD FOR PRODUCING A MICROELECTROMECHANICAL OSCILLATION SYSTEM AND PIEZOELECTRIC MICROMACHINED ULTRASONIC TRANSDUCER

• Main Authors: Schary, Timo, Brehm, Jan David, Roedel, Reinhold, Raible, Isabelle, Baader, Johannes
• Format: Patent
• Language: English
• Published: 02.05.2024
• Subjects: ELECTRICITY; FOR PERFORMING MECHANICAL WORK IN GENERAL; GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS IN GENERAL; METHODS OR APPARATUS FOR GENERATING OR TRANSMITTING MECHANICALVIBRATIONS OF INFRASONIC, SONIC, OR ULTRASONIC FREQUENCY; PERFORMING OPERATIONS; TRANSPORTING

A method for producing a microelectromechanical oscillation system. A carrier substrate having a first surface is provided. A circumferential first trench is produced, which extends from the first surface at least partially through the carrier substrate. A passivation layer is applied to the first surface of the first carrier substrate and the first circumferential trench is at least partially filled with the passivation layer. A first polysilicon layer is grown on the passivation layer and/or the first surface of the carrier substrate. A transducer element of the microelectromechanical oscillation system is arranged on a second surface of the first polysilicon layer. A second trench is produced through the carrier substrate in the direction of the transducer element, which extends up to the passivation layer so that the oscillatable transducer plate of the microelectromechanical oscillation system is produced adjacent to the second trench using the first polysilicon layer.