Abstract: 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.

Abstract: 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.

Abstract: In some examples, a capacitive micromachined ultrasonic transducer (CMUT) array may include a plurality of CMUT elements arranged in a plurality of rows, each row including multiple CMUT elements. A bias voltage supply may be connected for supplying bias voltages to a first row, a second row, and a third row of the plurality of rows. In addition, a processor may be configured by executable instructions to control the bias voltages by applying a first bias voltage to the second row, and a second, different bias voltage to the first and third rows to configure the CMUT elements of the second row to at least one of transmit or receive ultrasonic energy with different efficiency than the CMUT elements of the first row and the third row. In some examples, individual contributions from different rows can be computed from different firing sequences for synthetic aperture beamformation in an elevation dimension.

Abstract: 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.

Abstract: 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.

Abstract: 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.