102 results about "Surface micromachining" patented technology

A method for adjusting with high precision the width of gaps between micromachined structures or devices in an epitaxial reactor environment. Providing a partially formed micromechanical device, comprising a substrate layer, a sacrificial layer including silicon dioxide deposited or grown on the substrate and etched to create desired holes and/or trenches through to the substrate layer, and a function layer deposited on the sacrificial layer and the exposed portions of the substrate layer and then etched to define micromechanical structures or devices therein. The etching process exposes the sacrificial layer underlying the removed function layer material. Cleaning residues from the surface of the device, then epitaxially depositing a layer of gap narrowing material selectively on the surfaces of the device. The selection of deposition surfaces determined by choice of materials and the temperature and pressure of the epitaxy carrier gas. The gap narrowing epitaxial deposition continues until a desired gap width is achieved, as determined by, for example, an optical detection arrangement. Following the gap narrowing step, the micromachined structures or devices may be released from their respective underlying sacrificial layer.

Stiffened surface micromachined structures and a method to fabricate the same. A silicon substrate (10) is first etched to produce a mold containing a plurality of trenches or grooves (14) in a lattice configuration. Sacrificial oxide (15) is then grown on the silicon substrate (10) and then a stiffening member (16) (silicon nitride) is deposited over the surface of the substrate, thereby backfilling the grooves with silicon nitride. The silicon nitride is patterned to form mechanical members and metal (40) is then deposited and patterned to form the leads and capacitors for electrostatic actuation of mechanical members. The underlying silicon and sacrificial oxides are removed by etching the mold from underneath the fabricated micromachined devices, leaving free-standing silicon nitride devices with vertical ribs. The devices exhibit increased out-of-plan bending stiffness because of the presence of stiffening ribs. Silicon nitride biaxial pointing mirrors with stiffening ribs are also described.

The present invention provides a fabrication process that integrates high-aspect-ratio silicon structures with polysilicon surface micromachined structures. In some embodiments the process includes forming an oxide block by etching a plurality of trenches to leave a plurality of vertical-walled silicon structures standing on the substrate, thermally and substantially completely oxidizing the vertical-walled silicon structures, and substantially filling spaces between the oxidized vertical-walled silicon structures with an oxide of silicon to form the oxide block. The process retains not only the high-aspect-ratio silicon structures possible with deep reactive ion etching (DRIE) but also the design flexibility of polysilicon surface micromachining. Using this process, polysilicon platforms have been fabricated, which are actuated by high-aspect-ratio combdrives for many applications such as x-y-z stages and scanning devices. The actuators include an asymmetric combdrive that actuates in torsional/out-of-plane motions, and a high-aspect-ratio combdrive that drives in translational motion.

Robust microfluidic mixing devices mix multiple fluid streams passively, without the use of moving parts. In one embodiment, these devices contain microfluidic channels that are formed in various layers of a three-dimensional structure. Mixing may be accomplished with various manipulations of fluid flow paths and/or contacts between fluid streams. In various embodiments, structures such as channel overlaps, slits, converging/diverging regions, turns, and/or apertures may be designed into a mixing device. Mixing devices may be rapidly constructed and prototyped using a stencil construction method in which channels are cut through the entire thickness of a material layer, although other construction methods including surface micromachining techniques may be used.

A microscale cylindrical ion trap, having an inner radius of order one micron, can be fabricated using surface micromachining techniques and materials known to the integrated circuits manufacturing and microelectromechanical systems industries. Micromachining methods enable batch fabrication, reduced manufacturing costs, dimensional and positional precision, and monolithic integration of massive arrays of ion traps with microscale ion generation and detection devices. Massive arraying enables the microscale cylindrical ion trap to retain the resolution, sensitivity, and mass range advantages necessary for high chemical selectivity. The microscale CIT has a reduced ion mean free path, allowing operation at higher pressures with less expensive and less bulky vacuum pumping system, and with lower battery power than conventional- and miniature-sized ion traps. The reduced electrode voltage enables integration of the microscale cylindrical ion trap with on-chip integrated circuit-based rf operation and detection electronics (i.e., cell phone electronics). Therefore, the full performance advantages of microscale cylindrical ion traps can be realized in truly field portable, handheld microanalysis systems.

Robust microfluidic mixing devices mix multiple fluid streams passively, without the use of moving parts. In one embodiment, these devices contain microfluidic channels that are formed in various layers of a three-dimensional structure. Mixing may be accomplished with various manipulations of fluid flow paths and/or contacts between fluid streams. In various embodiments, structures such as channel overlaps, slits, converging/diverging regions, turns, and/or apertures may be designed into a mixing device. Mixing devices may be rapidly constructed and prototyped using a stencil construction method in which channels are cut through the entire thickness of a material layer, although other construction methods including surface micromachining techniques may be used.

The invention belongs to the technical field of surface treatment, and relates to a nano superhydrophobic surface used for airplane antifreezing and deicing and a preparation method thereof. The preparation method comprises the following steps: making a hydrophobic microstructure on a substrate by non-silicon surface micromachining technology or microreplication method; coating a nano decorative film on the surface of the hydrophobic microstructure; and baking the prepared hydrophobic microstructure and the substrate coated with the nano decorative film to obtain the dry and clean superhydrophobic surface. The nano superhydrophobic surface improves the contact properties between the surface of an airplane and waterdrops and greatly reduces the degree that a fuselage is infiltrated by the waterdrops; and the nano decorative film can also further reduce the viscous force of the waterdrops when the waterdrops slip the surface of the fuselage, the number of the waterdrops condensed on the surface of the fuselage is reduced, the icing degree on the surface of the airplane is effectively reduced, and the aim of high-efficiency, clean and low-cost airplane ice prevention/removal is achieved.

A structure which prevents thinning and disconnection of a wiring is provided, in a micromachine (MEMS structure body) formed with a surface micromachining technology. A wiring (upper auxiliary wiring) over a sacrificial layer is electrically connected to a different wiring (upper connection wiring) over the sacrificial layer, so that thinning, disconnection, and the like of the wiring formed over the sacrificial layer at a step portion generated due to the thickness of the sacrificial layer can be prevented. The wiring over the sacrificial layer is formed of the same conductive film as an upper driving electrode which is a movable electrode and is thus thin. However, the different wiring is formed over a structural layer, which is formed by a CVD method and has a rounded step, and has a thickness of 200 nm to 1 μm, whereby thinning, disconnection, and the like of the wiring can be further prevented.

An entirely surface micromachined free hanging strain-gauge pressure sensor is disclosed. The sensing element consists of a 80 μm long H-shaped double ended supported force transducing beam (16). The beam is located beneath and at one end attached to a square polysilicon diaphragm (14) and at the other end to the cavity edge. The sensor according to the invention enables a combination of high pressure sensitivity and miniature chip size as well as good environmental isolation. The pressure sensitivity for the sensor with a H-shaped force transducing beam, 0.4 μm thick was found to be 5 μV/V/mmHg.

A multi-dimensional, micro-electromechanical assembly and the method of fabricating same. The invention enables an assembly of three-dimensional (3D) microelectromechanical systems (MEMS) using surface tension or shrinkage self assembly. That is, the invention provides a surface tension self assembly technique for rotating a MEMS element with a controlled amount of deformation to a selected angle out of the plane of a substrate. In accordance with the inventive method, multi-dimensional, micro-electromechanical assemblies are fabricated by providing a phase change material on at least one substantially planar structure mounted in a first orientation. A phase change is induced in the phase change material whereby the phase change material changes from a first state, in which the structure is disposed in the first orientation, to a second state, in which the structure is disposed in a second orientation. The MEMS elements may be fabricated using conventional surface micromachining techniques. In the illustrative embodiment, each MEMS element is attached to a substrate by at least one hinge which allows rotation of the MEMS element out of the plane of the substrate to a selected angle. To enable mass assembly of the MEMS elements, the MEMS elements are rotated to the selected angle using either surface tension forces of a liquid phase change material or shrinkage of a solid phase change material. In the illustrative embodiment, the phase change material is solder and the step of inducing a phase change in the phase change material includes the step up applying heat.

The invention relates to a sound surface wave measuring sensor and a parameter analytical method. The sensor comprises a piezoelectric base, an interdigital transducer and a reflector, wherein the piezoelectric base is used for inducting physical quantity to be measured; the interdigital transducer and the reflector are deposited on the upper surface of the piezoelectric base through a surface micromachining process; the interdigital transducer is used for receiving drive energy required by the operation of the sound surface wave measuring sensor through an antenna connected with the interdigital transducer and returning a radio frequency pulse echo signal through the antenna; and the reflector is used for generating the radio frequency pulse echo signal. Compared with the prior art, the invention has the following technical characteristics: the physical quantity can be detected with high precision in a wide range on the premise of ensuring certain signal intensity; the problem that the sound surface wave sensor in the prior art can only meet one index in the range and the precision of signal measurement and the range and the precision of signal measurement cannot be met simultaneously is solved; the sound surface wave measuring sensor has simple structure; and by using a certain parameter analytical method, the measured physical quantity generates a corresponding feedback signal and the problem that the physical quantity can be accurately detected by the sensor in a wide range can be solved.

The invention discloses an electromagnetic-driven miniature two-dimensional scanning mirror device which belongs to the technical field of micro scanning and MEMS, is manufactured by adopting bulk silicon and surface micro machining technology and is actually a miniature two-dimensional scanning mirror device with two pairs of orthogonal magnetic poles. The scanning mirror device comprises a reflecting mirror surface, an inner baseplate, an outer baseplate, a base, inner torsion beams and outer torsion beams, wherein the reflecting mirror surface is integrally arranged on the inner baseplate; the inner baseplate is connected with the outer baseplate through a pair of opposite inner torsion beams; the outer baseplate is connected with the fixed base through the pair of opposite outer torsion beams; the inner torsion beams and the outer torsion beams are orthogonal. The scanning mirror device adopts a duralumin structure for encapsulation; two groups of magnet poles and magnetic yokes are arranged inside to form an orthogonal magnetic field; input signals are led in through the side wall of the encapsulating structure; a transparent glass seal cover is arranged at the top end of the encapsulating structure. The scanning mirror device has the advantages of high actuating efficiency, large torsion force and compact structure, and can realize two-dimensional scanning at larger angle.

MEMS in-plane resonators include a substrate wafer, at least one resonant mass supported by the substrate wafer and configured to resonate substantially in-plane, and at least one transducer coupled to the at least one resonant mass for at least one of driving and sensing in-plane movement of the at least one resonant mass, wherein at least part of one surface of the resonant mass is configured for exposure to an external environment and wherein the at least one transducer is isolated from the external environment. Such MEMS in-plane resonators may be fabricated using conventional surface micromachining techniques and high-volume wafer fabrication processes and may be configured for liquid applications (e.g., viscometry, densitometry, chemical/biological sensing), gas sensing (e.g., where a polymer film is added to the sensor surface, further degrading the damping performance), or other applications.

The invention relates to an absolute pressure sensor chip based on surface micromachining and a manufacturing method. The manufacturing method is characterized by comprising the following steps: adopting a low-stress silicon nitride film as a core structural layer of the pressure sensor chip and using a polycrystalline silicon film to form a force-sensitive resistor track; designing a film area of the low-stress silicon nitride film into a long rectangle, fully utilizing longitudinal piezoresistive effect of the polycrystalline silicon resistor track according to the stress distribution of the film area, and making the most of a tensile stress area on the film to put part of a pair of resistor tracks on the external surface of the film and arrange another two resistor tracks on the central position of the film; and separately contacting a folded bent angle part of each resistor track with a hole depositing metal to conduct the bent angle part. By adopting surface micromachining technology compatible with IC technology, the method can manufacture the absolute pressure sensor chip with a measuring range of 1KPa-1MPa and with high sensitivity, good stability and high precision.

The invention discloses a novel film bulk acoustic wave resonator, comprising an underlay, a piezoelectric film, an upper metal electrode layer and a lower metal electrode layer. The invention is characterized in that the invention also comprises a film support layer which is arranged on the underlay and is provided with the air gap structure in the contacting surface with the underlay; the film support layer, the lower metal electrode layer, the piezoelectric film and the upper metal electrode layer are overlapped successively upwards so as to form a resonance area. The resonator overcomes the defects in the prior art, and makes use of surface-micromachining technique and sacrificial layer technique without needing groove etching technique to silicon substrate and without needing chemical mechanical polishing technique. The invention greatly improves the feasibility of technique preparation, reduces production cost to a large extent, still has higher Q value and ensures the characteristics of the resonator.

The invention discloses an optoacoustic and ultrasonic bimodal endoscope imaging system. The optoacoustic and ultrasonic bimodal endoscope imaging system is composed of an endoscope lens, a light source, a controlling and processing device, an impulse voltage generator, an interface module, a cable, a display screen, a crystal oscillator circuit and a power circuit. The optoacoustic and ultrasonic bimodal endoscope imaging system can achieve endoscopic type optoacoustic and ultrasonic bimodal imaging. According to the optoacoustic and ultrasonic bimodal endoscope imaging system, a high density CMUT ring array manufactured by using surface micro fabrication technology is used, an excitation unit and a sensing unit are designed into coaxial and homocentric integrative microstructure, and integration, microminiaturization and practical performance of optoacoustic and ultrasonic excitation and sensing are achieved. The optoacoustic and ultrasonic bimodal endoscope imaging system can be widely used in fields of medical endoscopic diagnosis, jewelry identification, industrial inspection and flaw detection and the like.

A micromechanical relay is made by surface micromachining techniques. It includes a metallic cantilever beam deflectable by an electrostatic field and a beam contact connected to the beam and electrically insulated from the beam by an insulating segment. During operation, the beam deflects, and the beam contact establishes an electrical contact between two drain electrodes.

A scalable nano-electro-mechanical memory cell design that requires only conventional semiconductor fabrication materials and surface micromachining technology, and is suited for use in cross-point memory arrays for very high density non-volatile storage. This design also leverages well established surface-micromachining technology and electro-mechanical device phenomena to achieve an elegantly simple and scalable memory cell structure that can potentially operate with low voltage. An elongate beam is held between a non-deflected state and a deflected state, or between two deflected states, therein defining two binary memory states. Stiction, buried charge layers, or a combination of stiction and buried charge layers can be incorporated to modify the stability of one or both deflected states for the cell. Current through the moveable portion of the elongate beam within the memory cell can be registered utilizing one or more access transistors for reading the data state.

The invention discloses a method for testing film thermal conductivity. The method comprises the steps that: (1) with a surface micromachining technology, a double-end support cantilever beam structure is prepared, wherein the double-end support cantilever beam structure is composed of a film to be tested, a metal resistor strip on the film to be tested, and supporting blocks positioned on two ends below the film to be tested; (2) a proper direct current I is applied on the metal resistor strip I, such that temperature increasing is formed on the double-end support cantilever beam through the heating effect of currents; and (3) when thermal balance is reached, stable temperature increasing distribution is formed on the double-end support cantilever beam; and thermal conductivity is calculated according to voltage change value delta U on two poles in the inner side of the metal resistor strip, or according to delta UTCR value. According to the invention, compared with a commonly used 3omega method film thermal performance test method, the test structure processing process and testing means of the one-dimensional cantilever beam direct current method are relatively simple, and assist in providing more precise results.

Monolithically integrated capacitive micromachined transducers (CMTs) offer combined process steps, shared layers, simplified packaging, and reduced die size by overlapping the CMTs with the integrated circuit (IC) electronics. Moreover, a CMT array directly above the electronics also allows for varying the excitation signal phase to each CMT element thereby enabling beam-forming techniques. Above-IC integration is particularly attractive by not requiring any alteration of the semiconductor fabrication process and allowing subsequent implementation independent of IC fabrication. Naturally, this scheme requires that the CMT technology limit itself to IC compatible materials and chemicals, as well as process step temperatures within a specific thermal budget. Embodiments of the invention expanding upon surface micromachining technology allow the fabrication of IC-compatible CMT structures with superior mechanical properties and resistance to harsh environments such as high temperature, corrosive media and high-g shocks, by exploiting silicon carbide (SiC) structures to form the upper CMT structural layer.