Micromachined ultrasonic transducer devices with metal-semiconductor contact for reduced capacitive cross-talk

摘要

Embodiments reduce capacitive cross-talk between micromachined ultrasonic transducer (MUT) arrays through grounding of the substrate over which the arrays are fabricated. In embodiments, a metal-semiconductor contact is formed to a semiconductor device layer of a substrate and coupled to a ground plane common to a first electrode of the transducer elements to suppress capacitive coupling of signal lines connected to a second electrode of the transducer elements.

主权项

1. A micromachined ultrasonic transducer (MUT) array, comprising:
a plurality of transducer elements disposed over an area of a first side of a substrate, each of the plurality of transducer elements including a reference electrode and a signal electrode, wherein the respective reference electrodes of the plurality of transducer elements are interconnected to each other and coupled each to a reference potential plane that is distinct from the substrate, wherein the reference potential plane is configured to provide a reference potential directly to the respective reference electrodes via a conductive path that is independent of the substrate; a dielectric layer disposed between the respective reference electrodes of the plurality of transducer elements and the first side of the substrate, the dielectric layer forming a hole that extends to the first side of the substrate; a metal-semiconductor contact formed at the hole by one of the respective reference electrodes of the plurality of transducer elements with a semiconductor layer at the first side of the substrate; and one or more conductive traces connecting the metal-semiconductor contact to the reference potential plane, wherein the substrate is coupled to the reference potential plane via the metal-semiconductor contact and the one or more conductive traces.