Abstract: Micromachined ultrasonic transducers integrated with complementary metal oxide semiconductor (CMOS) substrates are described, as well as methods of fabricating such devices. Fabrication may involve two separate wafer bonding steps. Wafer bonding may be used to fabricate sealed cavities in a substrate. Wafer bonding may also be used to bond the substrate to another substrate, such as a CMOS wafer. At least the second wafer bonding may be performed at a low temperature.

Abstract: A universal ultrasound device having an ultrasound includes a semiconductor die; a plurality of ultrasonic transducers integrated on the semiconductor die, the plurality of ultrasonic transducers configured to operate a first mode associated with a first frequency range and a second mode associated with a second frequency range, wherein the first frequency range is at least partially non-overlapping with the second frequency range; and control circuitry configured to: control the plurality of ultrasonic transducers to generate and/or detect ultrasound signals having frequencies in the first frequency range, in response to receiving an indication to operate the ultrasound probe in the first mode; and control the plurality of ultrasonic transducers to generate and/or detect ultrasound signals having frequencies in the second frequency range, in response to receiving an indication to operate the ultrasound probe in the second mode.

Abstract: Processes for fabricating capacitive micromachined ultrasonic transducers (CMUTs) are described, as are CMUTs of various doping configurations. An insulating layer separating conductive layers of a CMUT may be formed by forming the layer on a lightly doped epitaxial semiconductor layer. Dopants may be diffused from a semiconductor substrate into the epitaxial semiconductor layer, without diffusing into the insulating layer. CMUTs with different configurations of N-type and P-type doping are also described.

Abstract: Micromachined ultrasonic transducers integrated with complementary metal oxide semiconductor (CMOS) substrates are described, as well as methods of fabricating such devices. Fabrication may involve two separate wafer bonding steps. Wafer bonding may be used to fabricate sealed cavities in a substrate. Wafer bonding may also be used to bond the substrate to another substrate, such as a CMOS wafer. At least the second wafer bonding may be performed at a low temperature.

Abstract: Micromachined ultrasonic transducers formed in complementary metal oxide semiconductor (CMOS) wafers are described, as are methods of fabricating such devices. A metallization layer of a CMOS wafer may be removed by sacrificial release to create a cavity of an ultrasonic transducer. Remaining layers may form a membrane of the ultrasonic transducer.

Abstract: Micromachined ultrasonic transducers integrated with complementary metal oxide semiconductor (CMOS) substrates are described, as well as methods of fabricating such devices. Fabrication may involve two separate wafer bonding steps. Wafer bonding may be used to fabricate sealed cavities in a substrate. Wafer bonding may also be used to bond the substrate to another substrate, such as a CMOS wafer. At least the second wafer bonding may be performed at a low temperature.

Abstract: An ultrasonic transducer includes a membrane, a bottom electrode, and a plurality of cavities disposed between the membrane and the bottom electrode, each of the plurality of cavities corresponding to an individual transducer cell. Portions of the bottom electrode corresponding to each individual transducer cell are electrically isolated from one another. Each portion of the bottom electrode corresponds to each individual transducer that cell further includes a first bottom electrode portion and a second bottom electrode portion, the first and second bottom electrode portions electrically isolated from one another.

Abstract: An ultrasound-on-a-chip device has an ultrasonic transducer substrate with plurality of transducer cells, and an electrical substrate. For each transducer cell, one or more conductive bond connections are disposed between the ultrasonic transducer substrate and the electrical substrate. Examples of electrical substrates include CMOS chips, integrated circuits including analog circuits, interposers and printed circuit boards.

Abstract: An ultrasonic transducer includes a membrane, a bottom electrode, and a plurality of cavities disposed between the membrane and the bottom electrode, each of the plurality of cavities corresponding to an individual transducer cell. Portions of the bottom electrode corresponding to each individual transducer cell are electrically isolated from one another. Each portion of the bottom electrode corresponds to each individual transducer that cell further includes a first bottom electrode portion and a second bottom electrode portion, the first and second bottom electrode portions electrically isolated from one another.

Abstract: An ultrasonic transducer includes a membrane, a bottom electrode, and a plurality of cavities disposed between the membrane and the bottom electrode, each of the plurality of cavities corresponding to an individual transducer cell. Portions of the bottom electrode corresponding to each individual transducer cell are electrically isolated from one another. Each portion of the bottom electrode corresponds to each individual transducer that cell further includes a first bottom electrode portion and a second bottom electrode portion, the first and second bottom electrode portions electrically isolated from one another.

Abstract: An ultrasound-on-a-chip device has an ultrasonic transducer substrate with plurality of transducer cells, and an electrical substrate. For each transducer cell, one or more conductive bond connections are disposed between the ultrasonic transducer substrate and the electrical substrate. Examples of electrical substrates include CMOS chips, integrated circuits including analog circuits, interposers and printed circuit boards.

Abstract: The disclosed embodiments relate to a portable ultrasound device. Specifically, the disclosed embodiments relate to an acoustic lens positioned at an ultrasound probe. The acoustic lens may be configured for impedance matching and signal attenuation. In one embodiment, ultrasound signal attenuation is provided by forming an acoustic lens as a solid admixture of signal attenuating particles in a polymer matrix.

Abstract: The disclosed embodiments relate to a portable ultrasound device. Specifically, the disclosed embodiments relate to an acoustic lens positioned at an ultrasound probe. The acoustic lens may be configured for impedance matching and signal attenuation. In one embodiment, ultrasound signal attenuation is provided by forming an acoustic lens as a solid admixture of signal attenuating particles in a polymer matrix.

Abstract: Aspects of the technology described herein relate to an ultrasound device including a first die that includes an ultrasonic transducer, a first application-specific integrated circuit (ASIC) that is bonded to the first die and includes a pulser, and a second ASIC in communication with the second ASIC that includes integrated digital receive circuitry. In some embodiments, the first ASIC may be bonded to the second ASIC and the second ASIC may include analog processing circuitry and an analog-to-digital converter. In such embodiments, the second ASIC may include a through-silicon via (TSV) facilitating communication between the first ASIC and the second ASIC. In some embodiments, SERDES circuitry facilitates communication between the first ASIC and the second ASIC and the first ASIC includes analog processing circuitry and an analog-to-digital converter. In some embodiments, the technology node of the first ASIC is different from the technology node of the second ASIC.

Abstract: Aspects of the technology described herein relate to an ultrasound device including a first die that includes an ultrasonic transducer, a first application-specific integrated circuit (ASIC) that is bonded to the first die and includes a pulser, and a second ASIC in communication with the second ASIC that includes integrated digital receive circuitry. In some embodiments, the first ASIC may be bonded to the second ASIC and the second ASIC may include analog processing circuitry and an analog-to-digital converter. In such embodiments, the second ASIC may include a through-silicon via (TSV) facilitating communication between the first ASIC and the second ASIC. In some embodiments, SERDES circuitry facilitates communication between the first ASIC and the second ASIC and the first ASIC includes analog processing circuitry and an analog-to-digital converter. In some embodiments, the technology node of the first ASIC is different from the technology node of the second ASIC.

Abstract: The disclosed embodiments relate to a portable ultrasound device. Specifically, the disclosed embodiments relate to an acoustic lens positioned at an ultrasound probe. The acoustic lens may be configured for impedance matching and signal attenuation. In one embodiment, ultrasound signal attenuation is provided by forming an acoustic lens as a solid admixture of signal attenuating particles in a polymer matrix.

Abstract: An ultrasonic transducer includes a membrane, a bottom electrode, and a plurality of cavities disposed between the membrane and the bottom electrode, each of the plurality of cavities corresponding to an individual transducer cell. Portions of the bottom electrode corresponding to each individual transducer cell are electrically isolated from one another. Each portion of the bottom electrode corresponds to each individual transducer that cell further includes a first bottom electrode portion and a second bottom electrode portion, the first and second bottom electrode portions electrically isolated from one another.

Abstract: Micromachined ultrasonic transducers formed in complementary metal oxide semiconductor (CMOS) wafers are described, as are methods of fabricating such devices. A metallization layer of a CMOS wafer may be removed by sacrificial release to create a cavity of an ultrasonic transducer. Remaining layers may form a membrane of the ultrasonic transducer.

Abstract: Aspects of the technology described herein relate to an ultrasound device including a first die that includes an ultrasonic transducer, a first application-specific integrated circuit (ASIC) that is bonded to the first die and includes a pulser, and a second ASIC in communication with the second ASIC that includes integrated digital receive circuitry. In some embodiments, the first ASIC may be bonded to the second ASIC and the second ASIC may include analog processing circuitry and an analog-to-digital converter. In such embodiments, the second ASIC may include a through-silicon via (TSV) facilitating communication between the first ASIC and the second ASIC. In some embodiments, SERDES circuitry facilitates communication between the first ASIC and the second ASIC and the first ASIC includes analog processing circuitry and an analog-to-digital converter. In some embodiments, the technology node of the first ASIC is different from the technology node of the second ASIC.

Abstract: Electrical biasing of ultrasonic transducers of an ultrasound device is described. The ultrasonic transducers may be capacitive micromachined ultrasonic transducers (CMUTs). The ultrasonic transducers may be grouped together, with the different groups receiving different bias voltages. The bias voltages for the various groups of ultrasonic transducers may be selected to account for differences between the groups.