Kolo Medical, Ltd.

Leland Stanford Junior University

Xuefeng Zhuang

Yongli Huang

Danhua Zhao

Butrus Thomas Khuri-Yakub

Lei Chen

Arif Sanli Ergun

Dave Hong

Ching-Hsiang Cheng

In some examples, a method of fabricating a transducer includes disposing a plurality of anchors on a substrate and disposing a sealing material and a device layer over the anchors and the substrate to form a cavity, the sealing material sealing the cavity. The method may further include forming, in the device layer, a plate and at least one spring member. The at least one spring member may be supported by at least one anchor of the plurality of anchors, and the at least one spring member may support the plate to allow relative movement between the plate and the substrate.

High displacement ultrasonic transducer

In some examples, a CMUT may include a plurality of electrodes, and each electrode may include a plurality of sub-electrodes. For instance, a first sub-electrode and a second sub-electrode may be disposed on opposite sides of a third sub-electrode. In some cases, a first bias voltage may be applied to the third sub-electrode and a second bias voltage may be applied to the first and second sub-electrodes while causing at least one of the first sub-electrode, the second sub-electrode, or the third sub-electrode to transmit and/or receive ultrasonic energy. For example, the second bias voltage may be applied at a different voltage amount than the first bias voltage, and/or may be applied at a different timing than the first bias voltage.

Bias control for capacitive micromachined ultrasonic transducers

In some examples, a CMUT array may include a plurality of elements, and each element may include a plurality of sub-elements. For instance, a first sub-element and a second sub-element may be disposed on opposite sides of a third sub-element. In some cases, the third sub-element may be configured to transmit ultrasonic energy at a higher center frequency than at least one of the first sub-element or the second sub-element. Further, in some instances, the sub-elements may have a plurality of regions in which different regions are configured to transmit ultrasonic energy at different resonant frequencies. For instance, the resonant frequencies of a plurality of CMUT cells in each sub-element may decrease in an elevation direction from a center of each element toward the edges of the CMUT array.

Capacitive micromachined ultrasound transducers having varying properties

In some examples, a capacitive micromachined ultrasonic transducer (CMUT) includes a first electrode and a second electrode. The CMUT may be connectable to a bias voltage supply for supplying a bias voltage, and a transmit and/or receive (TX/RX) circuit. In some cases, a first capacitor having a first electrode may be electrically connected to the first electrode of the CMUT, the first capacitor having a second electrode that may be electrically connected to the TX/RX circuit. Furthermore, a first resistor may include a first electrode electrically connected to the first electrode of the first capacitor and the first electrode of the CMUT. A second electrode of the first resistor may be electrically connected to at least one of: a ground or common return path, or the second electrode of the first capacitor.

Bias application for capacitive micromachined ultrasonic transducers

In some examples, a transducer apparatus includes a spring structure that enables a large, reliable amount of displacement of a transducer plate. For instance, an individual cell of the transducer apparatus may include a substrate having a first electrode portion, with at least one spring anchor extending from a first side of the substrate. At least one spring member may be supported by the at least one anchor, and may be connected to a plate that includes a second electrode portion. Accordingly, the spring member may support the plate, at least in part, for enabling the plate to move in a resilient manner toward and away from the substrate. In some cases, the spring member may be a bar-shaped spring that is cantilevered to an anchor or supported by two or more anchors. Additionally, a cavity between the plate and the substrate may be sealed by a sealing material.

A one or two-dimensional capacitive micro-machined ultrasonic transducer (CMUT) array with supporting frame is provided. The CMUT array has at least three array elements deposited on a conductive substrate. The invention also has at least one CMUT cell in the array element, a conductive top layer deposited to a top side of the element, and a conductive via disposed within the elements. The via is isolated from the conductive top layer and conducts with the substrate. There are at least two isolation trenches in the conductive substrate, and the trenches are disposed between adjacent vias to conductively isolating the vias. A substrate region between the trenches forms a mechanical support frame. At least one conductive electrode is deposited to a bottom surface of the conductive substrate, where the electrode conducts with the via. The support frame eliminates the need for a carrier wafer in the process steps.

Trench isolated capacitive micromachined ultrasonic transducer arrays with a supporting frame

The embodiments of the present invention provide a CMUT array and method of fabricating the same. The CMUT array has CMUT elements individually or respectively addressable from a backside of a substrate on which the CMUT array is fabricated. In one embodiment, a CMUT array is formed on a front side of a very high conductivity silicon substrate. Through wafer trenches are etched into the substrate from the backside of the substrate to electrically isolate individual CMUT elements formed on the front side of the substrate. Electrodes are formed on the backside of the substrate to individually address the CMUT elements through the substrate.

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San Jose, CA, United States of America

Xuefeng Zhuang