13 results about "Piezoelectric mems" patented technology

This application relates to the field of acoustic transducers, and particularly to a high-sensitivity MEMS acoustic device and its fabrication method. The high-sensitivity MEMS acoustic device is composed of an upper electrode layer, a piezoelectric layer, a lower electrode layer, a passive layer, an insulating layer, and a substrate connected in sequence. The multilayer composite film is radially symmetrical on the passive layer. A slit through the center of radial symmetry divides the composite film into several partitions. The upper and lower electrode layers of each partition are respectively provided with pads for signal extraction. The voltage signals of the pads in each partition are extracted through series or parallel connection. This application increases the output voltage by dividing the piezoelectric sensitive composite film into multiple sensitive regions and combining the sensitive regions in series, antiphase superposition, or other forms, thereby improving the sensitivity of the piezoelectric MEMS device.

The application discloses a piezoelectric MEMS device preparation process and a device structure, and relates to the technical field of piezoelectric MEMS device preparation. The preparation process comprises the following steps: forming a groove near an edge region on a front surface of a substrate, depositing a sacrifice layer on the front surface of the substrate and patterning the sacrifice layer, so that the sacrifice layer is separated into a center region and an edge support region, forming a piezoelectric-buffer stack on the sacrifice layer and patterning the piezoelectric-buffer stack, and opening a release hole, the release hole being communicated with the center region of the sacrifice layer, introducing etching medium into the release hole to remove the center region of the sacrifice layer, and then etching a back cavity on the back surface of the substrate. The application limits the size of a diaphragm region through the groove, etches the back cavity of the substrate after the sacrifice layer is released, and compared with a traditional method of defining the diaphragm by etching the back cavity, the application completely avoids the size error of the diaphragm caused by the angle deviation of deep silicon etching, accurately locks the profile of the diaphragm, and greatly improves the size consistency and performance stability of devices in the same batch.

The application provides a piezoelectric MEMS hydrophone based on a bionic cochlea structure and a preparation method thereof. The preparation method comprises the following steps: forming a blocking layer, a lower electrode layer, a piezoelectric layer and an upper electrode layer on a substrate, and forming a hard mask on the back of the substrate; performing photoetching on the upper electrode layer and then performing reactive ion beam etching to obtain a bionic cochlea structure pattern; performing photoetching and patterning on the piezoelectric layer to obtain a bionic cochlea structure pattern, and then etching to expose the lower electrode layer; forming a positive electrode and a negative electrode on the upper electrode layer; forming an etched hard mask; performing deep silicon etching steps on the back after photoetching and patterning to obtain a back bionic cochlea spiral cavity structure and in-situ arrayed cilia; etching and releasing the device; bonding the piezoelectric vector hydrophone with a PCB board, and wire-bonding the positive electrode and the negative electrode with the PCB board. The hydrophone has the characteristics of miniaturization, realizes wide-frequency underwater sound detection by using a bionic cochlea spiral diaphragm structure, and improves detection sensitivity by using in-situ integrated bionic cochlea cilia.

The application relates to the field of semiconductor devices and provides a piezoelectric MEMS resonator and an electronic component. The resonator comprises a cap wafer and a device wafer, the cap wafer comprises a cap layer, and the device wafer comprises: a substrate layer; a resonant cavity arranged on the substrate layer; a device silicon layer located on the upper side of the resonant cavity; a piezoelectric layer located on the upper side of the device silicon layer; a top electrode located on the upper side of the piezoelectric layer; and a first dielectric layer located on the upper side of the top electrode and covering the top electrode, the first dielectric layer is bonded to the cap layer, at least a part of the first dielectric layer bonded to the cap layer projects on the vertical direction and overlaps the projection of the top electrode on the vertical direction, and the upper surface of the at least part of the first dielectric layer bonded to the cap layer is in the same plane. In this way, the bonding properties of the cap wafer and the device wafer are improved by flattening the surface of the dielectric layer covering the top electrode, and a good bonding effect is ensured.

This invention relates to piezoelectric MEMS fans and their stress optimization design, fabrication, and chip in the field of MEMS actuators. The piezoelectric MEMS fan includes a support frame and at least one piezoelectric motion arm extending from the support frame. The piezoelectric motion arm has multiple stress-dispersing openings, and the distribution pattern of these openings is configured to disperse stress concentration within the piezoelectric motion arm during vibration. This invention designs a specific stress-dispersing opening pattern on the piezoelectric motion arm, which is optimized based on vibration stress field analysis. This pattern effectively disperses and releases the alternating stress borne by the motion arm during long-term high-frequency vibration, especially alleviating stress concentration in critical areas such as the root, thereby greatly suppressing the initiation and propagation of fatigue cracks and reducing performance degradation and the probability of fracture failure.

A system for compensating for thermal stress in piezoelectric microelectromechanical systems devices can have a piezoelectric layer at least partially spanning a cavity such that it generates electrical signals when external forces cause the piezoelectric layer to vibrate with respect to the cavity. At least one electrode layer can include a conductive metal positioned adjacent the piezoelectric layer and configured as an electrode to accept the electrical signals. The piezoelectric layer and electrode layer can have an expected thermal stress tending to cause expected deflection even when external forces are not causing the piezoelectric layer to vibrate. A compensation layer can be positioned adjacent at least one of the piezoelectric layer and the at least one electrode layer and configured to counteract the expected deflection from the expected thermal stress.

This invention discloses a piezoelectric MEMS device, its fabrication method, and its applications, belonging to the field of microelectromechanical systems (MEMS) technology. The fabrication method includes: preparing an SOI wafer; performing PSG spin-coating annealing and / or metallization modification on the device layer surface to form a conductive seed layer; depositing a piezoelectric layer; simultaneously etching the insulating layer, modified device layer, and piezoelectric layer using a specific mixed gas or pulse modulation process; forming a metal electrode layer and a bonding metal layer; and bonding and integrating with a TSV structure. This invention replaces traditional metal electrodes with metallization modification, avoiding electrode fatigue and aging, and improving device reliability; the use of single-mask synchronous etching and vapor phase release technology eliminates overlay and bonding errors, reducing process complexity and cost, making it suitable for high-performance sensors, ultrasonic detection, audio, and smart hardware.

The application discloses a MEMS sound wave sensor with scalar and vector composite sensing and a manufacturing method thereof, and belongs to the technical field of micro-electro-mechanical systems. The piezoelectric film, the scalar lower lead wire area and the scalar upper lead wire area constitute a piezoelectric MEMS sensor for sensing scalar sound wave information; the upper plate vector lead wire area, the upper plate, the upper plate lower insulating layer, the upper plate limiting concave frame, the upper plate anti-collision convex point, the back-shaped upper cantilever beam group, the vector lead wire area, the back-shaped lower cantilever beam group, the mass block, the support frame, the lower plate upper insulating layer, the lower plate limiting concave frame, the lower plate anti-collision convex point, the lower plate, the lower plate vector lead wire area constitute a sandwich type differential capacitance MEMS sensor for sensing vector sound wave information. The application has the advantages of scalar and vector composite sensing, small volume, large range, high sensitivity, high reliability, high integration, low cost, low noise, stable performance and the like.

This application discloses a single-crystal piezoelectric MEMS device and its fabrication method, belonging to the field of MEMS device processing technology. The method first fabricates through-holes on a piezoelectric material wafer, then fills the through-holes with a colloid. Next, a metal electrode layer is deposited on the back side of the piezoelectric material wafer using thin-film deposition technology, serving as the bottom electrode of the MEMS device. Then, the electrode surface of the single-crystal piezoelectric wafer is bonded to a substrate (silicon, glass, SOI, or SiO2 / Si layered structure). Subsequently, the single-crystal piezoelectric material is thinned to a predetermined thickness using a precision thinning process. The colloid within the through-holes is then removed to expose the bottom electrode. Finally, the remaining conventional MEMS fabrication processes, such as top electrode deposition, structural layer patterning, and back cavity etching, are completed, ultimately realizing the fabrication of the piezoelectric MEMS device. This method provides a low-cost, efficient, and scalable manufacturing process, promoting the application and development of piezoelectric single-crystal thin films in the MEMS field.

The embodiment of the application discloses a piezoelectric MEMS hydrophone and a preparation method thereof, the piezoelectric MEMS hydrophone comprises: a substrate; a first end cover layer located on one side of the substrate and having a first gap with the substrate; a second end cover layer located on the side, away from the substrate, of the first end cover layer and having a second gap with the first end cover layer; a piezoelectric layer structure located on the side, away from the substrate, of the second end cover layer and having a third gap with the second end cover layer; a third end cover layer located on the side, away from the substrate, of the piezoelectric layer structure and having a fourth gap with the piezoelectric layer structure; one of the first and second end cover layers forms a first protrusion in a direction away from the piezoelectric layer structure, and the other forms a second protrusion in a direction away from the substrate, and the first protrusion and the second protrusion at least partially overlap in orthographic projection on the substrate. The technical scheme provided by the application increases the output voltage, effectively improves the sensitivity of the hydrophone and widens the bandwidth.

A piezoelectric MEMS cooler with a rectangular symmetrical slit structure, relating to the field of semiconductor cooling, includes: an orifice plate with a plurality of nozzles arranged on the orifice plate; an actuator disposed above the orifice plate, the actuator forming a cavity with the orifice plate, the top of the actuator having a transverse slit and a longitudinal slit, one transverse slit penetrating the actuator along the thickness direction, at least one longitudinal slit penetrating the actuator along the thickness direction, the transverse slit being perpendicular to each longitudinal slit, and each longitudinal slit being located at the equidistant points of the transverse slit; and a sealing membrane bonded to the top surface of the actuator and covering the transverse and longitudinal slits. This application employs a one-horizontal-multiple-vertical layout to divide the actuator into rectangular areas of uniform size and stiffness, ensuring that the vibration direction of each rectangular area is perpendicular to the actuator surface, improving the synchronization of the vibration height of each rectangular area, and ensuring that the superposition of the vibrations of each rectangular area can form a neat and concentrated airflow for uniform heat dissipation from the heat source.

The application discloses a preparation process and a device structure of a MEMS device based on front etching, and relates to the technical field of piezoelectric MEMS device preparation. The process comprises the following steps: forming a first groove and a second groove on the front surface of a substrate at the center of the substrate and near the edge of the substrate respectively; forming an adhesion layer and patterning the same, the adhesion layer is divided into a center region and an edge region by the second groove, a piezoelectric-buffer stack is formed on the adhesion layer and is patterned, a plurality of release holes are formed on the piezoelectric-buffer stack, an etching medium is introduced from the release holes, the center adhesion region of the adhesion layer is removed, and the piezoelectric-buffer stack corresponding to the center region is protruded to the side away from the substrate. The application does not need to etch and release a back cavity from the back of the device, thereby avoiding the size error, the alignment deviation and the substrate damage caused by the deep groove etching of the back cavity, effectively improving the consistency of the device structure size, and significantly improving the performance uniformity and the batch production yield of the piezoelectric MEMS device.