Patent ID: 11860272
Assignee: INFINEON TECHNOLOGIES AG
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 10:
11. A method for manufacturing an ultrasonic touch sensor, the method comprising:
providing a covering coupled to a housing, wherein an internal area is defined between the housing and the covering, and wherein the covering has a contact face configured to receive a touch;
providing a first semiconductor chip having a first ultrasonic transducer element, wherein the first ultrasonic transducer element is arranged in the internal area such that the first ultrasonic transducer element is configured to transmit an ultrasonic transmit wave towards the covering,
wherein a touch interface at the contact face of the covering is configured to

reflect the ultrasonic transmit wave into the internal area as an ultrasonic reflected wave;
providing a second ultrasonic transducer element in the internal area such that the second ultrasonic transducer element is configured to receive the ultrasonic reflected wave from the covering;
embedding the first semiconductor chip in a potting compound; and
forming a recess in the potting compound using laser ablation in order to form an acoustic barrier between the first ultrasonic transducer element and the second ultrasonic transducer element,
wherein the acoustic barrier is configured to reduce parasitic ultrasound waves originating from the ultrasonic transmit wave from reaching the second ultrasonic transducer element.