EP1196349A1 - Dispositifs microelectriques et leurs procedes de fabrication - Google Patents

Dispositifs microelectriques et leurs procedes de fabrication

Info

Publication number
EP1196349A1
EP1196349A1 EP00945011A EP00945011A EP1196349A1 EP 1196349 A1 EP1196349 A1 EP 1196349A1 EP 00945011 A EP00945011 A EP 00945011A EP 00945011 A EP00945011 A EP 00945011A EP 1196349 A1 EP1196349 A1 EP 1196349A1
Authority
EP
European Patent Office
Prior art keywords
substrate
sacrificial material
diaphragm layer
void
transducer
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP00945011A
Other languages
German (de)
English (en)
Inventor
Peter J. Schiller
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
University of Minnesota
Original Assignee
University of Minnesota
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by University of Minnesota filed Critical University of Minnesota
Publication of EP1196349A1 publication Critical patent/EP1196349A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B81—MICROSTRUCTURAL TECHNOLOGY
    • B81C—PROCESSES OR APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OR TREATMENT OF MICROSTRUCTURAL DEVICES OR SYSTEMS
    • B81C1/00—Manufacture or treatment of devices or systems in or on a substrate
    • B81C1/00015—Manufacture or treatment of devices or systems in or on a substrate for manufacturing microsystems
    • B81C1/00134—Manufacture or treatment of devices or systems in or on a substrate for manufacturing microsystems comprising flexible or deformable structures
    • B81C1/00182—Arrangements of deformable or non-deformable structures, e.g. membrane and cavity for use in a transducer
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B81—MICROSTRUCTURAL TECHNOLOGY
    • B81B—MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES
    • B81B2201/00—Specific applications of microelectromechanical systems
    • B81B2201/02—Sensors
    • B81B2201/0264—Pressure sensors
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B81—MICROSTRUCTURAL TECHNOLOGY
    • B81B—MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES
    • B81B2203/00—Basic microelectromechanical structures
    • B81B2203/01—Suspended structures, i.e. structures allowing a movement
    • B81B2203/0118—Cantilevers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B81—MICROSTRUCTURAL TECHNOLOGY
    • B81B—MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES
    • B81B2203/00—Basic microelectromechanical structures
    • B81B2203/01—Suspended structures, i.e. structures allowing a movement
    • B81B2203/0127—Diaphragms, i.e. structures separating two media that can control the passage from one medium to another; Membranes, i.e. diaphragms with filtering function
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B81—MICROSTRUCTURAL TECHNOLOGY
    • B81B—MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES
    • B81B2203/00—Basic microelectromechanical structures
    • B81B2203/03—Static structures
    • B81B2203/0315—Cavities
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B81—MICROSTRUCTURAL TECHNOLOGY
    • B81C—PROCESSES OR APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OR TREATMENT OF MICROSTRUCTURAL DEVICES OR SYSTEMS
    • B81C2201/00—Manufacture or treatment of microstructural devices or systems
    • B81C2201/01—Manufacture or treatment of microstructural devices or systems in or on a substrate
    • B81C2201/0101—Shaping material; Structuring the bulk substrate or layers on the substrate; Film patterning
    • B81C2201/0102—Surface micromachining
    • B81C2201/0105—Sacrificial layer
    • B81C2201/0109—Sacrificial layers not provided for in B81C2201/0107 - B81C2201/0108

Definitions

  • the present invention relates to the field of micro-electromechanical devices. More particularly, the present invention provides micro- electromechanical devices, substrate assemblies for forming such devices, and methods of manufacturing the substrate assemblies and devices.
  • Micro-electromechanical devices such as pressure sensors, actuators, etc. provide advantages in many different applications.
  • Two basic approaches have been developed to manufacture the devices using many well-known conventional integrated circuit manufacturing techniques.
  • the two basic approaches are typically referred to as surface micromachining and backside bulk rnicromachining.
  • encapsulation layers that are impervious to very aggressive chemicals used in forming the features on the front surface of the devices.
  • surface- inicromachining exposes the surface of the wafer to a variety of etchants and other removal processes.
  • the encapsulation layer may need to protect all vulnerable layers from highly-concentrated hydrofluoric acid (HF) liquid or vapor.
  • the encapsulation layer may need to protect all other materials from a heated potassium-hydroxide (KOH) or tetramethyl-ammonium-hydroxide (TMAH) solution.
  • KOH potassium-hydroxide
  • TMAH tetramethyl-ammonium-hydroxide
  • the encapsulation layer typically adds to the bulk of the devices and may also affect performance by, for example, increasing the stiffness of a diaphragm used in a pressure sensor or actuator. That additional stiffness may reduce sensitivity (in the case of, e.g., a sensor) and/or it may increase the power requirements for operating an actuator. To address these issues, it may be desirable to reduce the thickness of an encapsulation layer. Reducing the encapsulation layer thickness, however, increases the likelihood that the underlying features on the device will not be adequately protected, thereby reducing product yield. As a result, surface micromachined device performance is often limited by availability of a thin film technology suitable for encapsulation layers.
  • backside bulk-micromachining techniques also have tradeoffs.
  • the essence of backside silicon micromachining separates the machining operation from the fine-featured frontside.
  • this same characteristic also leads to the limitations of backside bulk-micromachining.
  • front-to-backside alignment defines the registration between the mechanical structure and the transducer elements.
  • the overlay capabilities are coarse and performance is lost.
  • the silicon etch proceeding from the backside will reach the frontside at a position dependent on the wafer thickness and/or etch profile distribution.
  • KOH potassium hydroxide
  • DRIE Deep Reactive Ion Etching
  • the etch profile varies with feature size and wafer position so that variations in finished dimensions can also be on the order of tens or even hundreds of microns within a single wafer. Combining alignment errors and etch profile variations, bulk machining techniques often lead to large discrepancies between the frontside-defined transducer elements and the mechanical structure.
  • the present invention provides micro-electromechanical devices, substrate assemblies from which the devices can be manufactured, and methods to manufacture the devices.
  • the invention combines the advantages of conventional surface and bulk niicromachining processes to create an integrated micro-electromechanical system (MEMS) technology that provides high performance, high yield, and manufacturing tolerance.
  • the devices manufactured according to the present invention include, but are not limited to, pressure sensors, vibration sensors, accelerometers, gas or liquid pumps, flow sensors, resonant devices, and infrared detectors.
  • One advantage of the present invention is that the mechanical integrity of the substrates on which the devices are formed is maintained until the last processing steps.
  • vibration sensors or accelerometers of the present invention may be used include navigational systems (automotive, aeronautic, personal, etc.); environmental monitors (seismic activity, traffic monitors, etc.); equipment monitors (industrial equipment, etc.); component monitors (fatigue/crack detection, shock threshold detection, etc.); and biomedical monitors (cardiac monitor, activity monitor, ultrasonic-GPS, etc.).
  • Nonlimiting examples of applications in which pressure sensors of the present invention may be used include aeronautics (altimeter, air velocity, etc.); combustion engine applications (combustion diagnostic, exhaust monitor, fuel monitor; etc.); and auditory applications (hearing aids, mini-microphones, etc.).
  • Nonlimiting examples of applications in which resonant structures of the present invention may be used include chemical sensing (electronic nose, military, biomedical, etc.) and environmental monitors (humidity, biohazard detection, pressure, etc.).
  • Nonlimiting examples of applications in which pumps of the present invention may be used include miniature vacuum systems (mass spectrometry, medical diagnostics, etc.); drug delivery (implanted drug delivery, precision external delivery, etc.); microfluidics (DNA chips, medical diagnostics, etc.); and sample extraction (environmental, biomedical, etc.).
  • the present invention provides a method of manufacturing a micro-electromechanical device having front and back sides, the method including providing a substrate having a first side located proximate the front side of the device and second side proximate the back side of the device; providing sacrificial material on a selected area of the first side of the substrate; providing a diaphragm layer on the sacrificial material and the first side of the substrate surrounding the sacrificial material in the selected area; providing at least one transducer on the front side of the device, the transducer located over the sacrificial material, wherein the transducer includes transducing material and electrical contacts in electrical communication with the transducing material; forming a void in the substrate from the second side of the substrate towards the first side of the substrate after providing the transducer on the front side of the device, wherein at least a portion of the sacrificial material is exposed within the void proximate the first side of the substrate; and removing at least a portion of the
  • the present invention provides a substrate assembly having front and back sides, the assembly including a substrate having a first side located proximate the front side of the device and second side proximate the back side of the substrate assembly; sacrificial material on the first side of the substrate in a plurality of selected areas; a diaphragm layer covering the sacrificial material in the selected areas, the diaphragm layer extending to cover the first side of the substrate surrounding the sacrificial material in the selected areas; a plurality of transducers on the front side of the device, each of the transducers located over at least a portion of each of the selected areas, wherein the transducer includes transducing material and electrical contacts in electrical communication with the transducing material; wherein the sacrificial material in the selected areas is encapsulated between the substrate and the diaphragm layer.
  • the present invention provides a micro- electromechanical device having front and back sides, the device including a substrate having a first side located proximate the front side of the device and second side proximate the back side of the device; a void formed through the first and second sides of the substrate, the void including an opening proximate the first side of the substrate; and a diaphragm layer spanning the opening in the first side of the substrate and attached to the first side of the substrate, wherein a portion of the diaphragm layer is suspended directly above a portion of the substrate surrounding the opening of the void; and wherein the suspended portion of the diaphragm layer and the substrate form an included angle at their junction of less than 90 degrees.
  • Figures 1A-1D illustrate one process of forming a vibration sensor according to the present invention.
  • Figure 2 is a schematic diagram of one etching apparatus that may be used in connection with the present invention.
  • Figures 3A & 3B are cross-sectional and plan views, respectively, of a pressure sensor.
  • Figures 4A & 4B are cross-sectional and plan views, respectively, of a resonant device.
  • Figures 5 A & 5B are cross-sectional and plan views, respectively, of a pump device.
  • frontside and backside processing technologies may provide a) high performance, b) repeatability, c) high yield, d) wide process margins, and e) ease of integration.
  • the vibration sensor relies on piezoelectric capacitors to convert mechanical strain to an electrical signal by virtue of the primary piezoelectric effect.
  • the method includes the use of a substrate 20 having a front surface 22 and a back surface 24. It will typically be preferred that the substrate 20 be manufactured of materials amenable to processing (e.g., etching) used in the production of integrated circuit devices. Examples of some suitable materials for the substrate 20 include, e.g., silicon wafers and similar structures. It may also be preferred that one or both of the surfaces 22 and 24 of the substrate 20 be planar to facilitate high resolution processing.
  • Sacrificial material 30 is then provided in selected areas on the front surface 22 of the substrate 20.
  • the thickness of the sacrificial material 30 in the selected areas may preferably be about 0.5 to about 1 micrometer.
  • the control over the selected areas in which the sacrificial material 30 is deposited may be accomplished, e.g., by using patterned photoresist material followed by deposition of the patterned material in the selected areas where the photoresist has been removed.
  • the sacrificial material 30 may be deposited over substantially all of the front surface 22, followed by patterning and removal of the sacrificial material, leaving the sacrificial material 30 in only the selected areas as illustrated in Figure 1A. Such techniques are well known and will not be described further herein.
  • the sacrificial material 30 is preferably selectively removable with respect to the underlying substrate 20. Where etching is to be used to form voids through the substrate 20 from the back surface 24 towards the front surface 22, it may be preferred that the sacrificial material act as an etch stop to halt etching when the void being formed reaches the underside of the sacrificial material 30.
  • preferred sacrificial material 30 Another characteristic that may be exhibited by preferred sacrificial material 30 is reflowability. In other words, after any patterning material (e.g., photoresist) is removed from around the selected areas in which the sacrificial material 30 has been deposited, it may be desirable that the sacrificial material 30 be reflowed to provide desirable smooth edges to the sacrificial material 30 in the selected areas.
  • a suitable reflowable sacrificial material 30 is phosphosilicate glass (PSG).
  • sacrificial material include heavily doped n+ silicon or polysilicon layers. N-type doping levels near the solid solubility limit accentuate the lateral etch rate in a variety of wet chemical and dry plasma etchants.
  • Wet chemical etchants commonly used to selectively etch n+ silicon or polysilicon include but are not limited to a) KOH, b) TMAH, and c) HF/HNO 3 .
  • Dry plasma etch agents commonly used to rapidly etch n+ silicon and polysilicon include but are not limited to a) C12, b) SF6, and c) other Cl- or F-containing gases. Other materials/etchants have been reported in the literature and may be appropriate for some applications within the method described here.
  • a diaphragm layer 40 is deposited over the sacrificial material 30 and on the front substrate surface 22 surrounding the selected areas.
  • the diaphragm layer 40 functions as a mechanical support layer over the sacrificial material 30 (which will be removed later) for the transducer to be formed over the selected areas of sacrificial material 30.
  • the diaphragm layer 40 may have any suitable thickness depending on the size of the selected areas of sacrificial material 30, the size of the transducer to be formed on the diaphragm layer 40, and other factors.
  • Suitable materials for the diaphragm layer 40 will exhibit sufficient mechanical strength to support the transducer structures to be deposited on it (after removal of the underlying sacrificial material 30) and the ability to flex during the sensing or actuating processes performed by the device.
  • the diaphragm layer 40 is also preferably formed of materials that are not electrically conductive. Examples of suitable materials include silicon nitride, silicon dioxide, etc. One preferred material may be a low-stress silicon nitride diaphragm layer 40 deposited at a thickness of about 2.0 micrometers.
  • conductive electrode layers 52 are provided in selected areas on the diaphragm layer 40.
  • the conductive electrode layers 52 may be provided by any suitable electrically conductive material that can be provided in the desired patterns on the diaphragm layer 40.
  • a suitable material for the conductive electrode layers 52 is doped polycrystalline silicon.
  • the electrode layer 52 may preferably form the lower electrodes for connection to, e.g., the transducer elements 50 provided over the selected areas containing the sacrificial material 30 (encapsulated between the diaphragm layer 40 and the substrate 20).
  • the transducer elements 50 may be formed of any suitable transducing material.
  • "transducing element” is any structure that exhibits a change in one or more measurable electrical properties when subjected to mechanical strain or which exhibits a mechanical force when subjected to an applied electrical stimulus.
  • transducing elements 50 may include layers of piezoelectric material, piezoresistive materials, electrically conductive materials, optically active materials (e.g., materials that exhibit some change in optical properties in response to strain, e.g., a change in transmissivity, absorbance, birefringence, etc.), magnetostrictive materials, magnetoresistive materials, etc.
  • optically active materials e.g., materials that exhibit some change in optical properties in response to strain, e.g., a change in transmissivity, absorbance, birefringence, etc.
  • magnetostrictive materials magnetoresistive materials, etc.
  • an upper electrode layer 56 is formed in electrical communication with the transducing element 50, such that the transducing element 50 is in electrical communication with both the lower electrode layer 52 and the upper electrode layer 56.
  • the upper electrode layer 56 is manufactured in a manner and using materials that are similar to those used for the lower electrode layer 52.
  • a piezoelectric capacitor is formed that converts mechanical strain in the diaphragm layer 40 to an electrical signal by virtue of the primary piezoelectric effect.
  • the structures provided on the diaphragm layer 40 also include contacts 54 and 58 that are in electrical communication with the lower electrode layer 52 and upper electrode layer 56, respectively.
  • the contact 54 in electrical communication with the lower electrode layer 52 may be used to supply, e.g., ground voltage to the transducer element 50 through the lower electrode layer 52.
  • the electrical contacts 54 and 58 may preferably be formed of a metal or metals to facilitate connection of the transducer element 50 to other devices.
  • Suitable metals used for the contacts 54 and 58 include any patternable metal or combination of metals used in integrated circuit manufacturing. Examples include, but are not limited to, aluminum, titanium, gold, platinum, tungsten, copper, etc.
  • Figure IB thus illustrates one substrate assembly from which a plurality of micro-electromechanical devices can be manufactured.
  • the voids 70 required to form the desired vibration sensor can be formed from the back surface 24 of the substrate 20.
  • the back surface 24 of the substrate 20 is patterned and etched using any suitable integrated circuit manufacturing technique or techniques. It may be desirable that the techniques used be selective to the material of the substrate 20 as opposed to the sacrificial material 30 located in the selected areas on the front surface 22 of the substrate.
  • a Deep Reactive Ion Etching (DRIE) process e.g., an SF 6 -based Bosch process
  • the etching preferably terminates at the underside of the sacrificial material 30 as illustrated in Figure lC.
  • the void 70 is provided in the shape of an annular ring (when viewed from above or below) that also defines the shape of a proof mass 80 located within the void 70 and attached to the diaphragm layer 40 within the area defined by the transducing elements 50.
  • the proof mass 80 is, as a result, a separated portion of the original substrate 20.
  • Other methods may also be used to form the void 70, although one advantage of DRJE is that the sidewalls of the void may be more orthogonal with respect to the back surface 24 of the substrate 20 as compared to other etching processes.
  • void 70 may alternatively be formed.
  • chlorinated gas species are often used for etching silicon and polysilicon.
  • plasma etching is not the only available method for etching through the silicon wafer.
  • Wet chemical agents such as KOH and TMAH are often used in bulk-micromachining process modules to etch from one side of a silicon wafer to the other. While such wet chemicals do not provide the same near-vertical etch profile, they may be substituted if DRIE technology is not available.
  • Removal of the sacrificial material 30 may preferably be accomplished by exposing only the back substrate surface 24 to gas phase hydrofluoric acid (HF) which selectively removes the preferred PSG sacrificial material 30 as opposed to the silicon substrate 20 and the preferred silicon nitride diaphragm layer 40.
  • HF gas phase hydrofluoric acid
  • the void 70 is formed and the sacrificial material 30 is removed without exposing the front of the device (with the contacts 54 and 58 and any other features) to the etchants or other materials used to form either the void 70 or remove the sacrificial material 30.
  • the removal can be performed by only exposing the back surface 24 of the substrate 20. No elaborate encapsulation is required for the front side of the device.
  • the vibration sensor thus formed as seen in cross-section in Figure ID includes a diaphragm layer 40, a portion of which is suspended directly above the substrate 20 surrounding the void 70.
  • the junction between the diaphragm layer 40 and the substrate 20 can be subject to fatigue as the sensor is used an the diaphragm layer 40 flexes. It may be desirable that the included angle formed between the front surface 22 of the substrate 20 and the underside 42 of the diaphragm layer 40 be less than 90 degrees to improve fatigue resistance of the sensor. It is in this area where the use of reflowable sacrificial material 30 may be beneficial. Reflowing the sacrificial material 30 after removing the patterning material can be used to provide sloping edges 32 on the sacrificial material 30.
  • Those sloped edges 32 can provide the desired included angle of less than 90 degrees at the junction of the diaphragm layer 40 and the substrate 20. It may be even more preferred that the included angle at the junction between the diaphragm layer 40 and the substrate 20 be about 75 degrees or less.
  • the included angle formed at the junction of the diaphragm layer 40 and the proof mass 80 is also preferably less than 90 degrees, possibly even more preferably about 75 degrees or less, to improve fatigue resistance there as well.
  • Figure 2 demonstrates one apparatus suitable for performing gas phase etching in a technique that exposes only the back surface 24 of the substrate 20 and the exposed undersides of the sacrificial material 30 to the etchant.
  • a container 90 is provided that contains, e.g., a liquid etchant (such as liquid-phase HF).
  • the substrate 20 is placed over the top 92 of the container 90 and sealed around its edges to expose only the back surface 24 of the substrate 20 to the etchant.
  • gaseous etchant may be trapped within the sealed container 90.
  • the HF vapor within the container 90 will typically reach an equilibrium concentration sufficient to rapidly etch the exposed PSG sacrificial material 30 exposed through the voids 70.
  • an inert gas such as nitrogen, argon, or just air
  • an inert gas such as nitrogen, argon, or just air
  • FIG. 1A-1D provide a vibration sensor using piezoelectric capacitors to convert mechanical strain in the membrane to an electrical signal by virtue of the primary piezoelectric effect.
  • the converse piezoelectric describes deformation (strain) of a piezoelectric material in response to an applied electric field or signal. That effect may be exploited in actuator-type devices such as resonators, pumps, valves, etc. wherein mechanical motion is the result of applied electrical energy.
  • a second material class embodiment substitutes piezoresistive elements for the piezoelectric capacitor. Piezoresistive materials demonstrate a change of electrical resistance in response to an applied mechanical stress or strain.
  • Common piezoresistive materials include but are not limited to a) thin film polycrystalline silicon of p- or n-type conductivity, b) single crystal silicon of p- or n-type conductivity, and c) various metallic materials such as platinum, gold, aluminum, etc.
  • a third embodiment for mechanical-to-electrical energy conversion involves electrostatics, most often in the form of capacitive sensors. When the physical separation of two electrical conductors is changed, the capacitance changes. Conductive layers in a device can be arranged such that the mechanical strain or displacement changes the capacitance, a property readily detected with conventional electronics. Conversely, electrostatics can be employed to create mechanical motion from electrical energy in much the same manner.
  • FIGs 3 A and 3B depict a piezoresistive pressure sensor 110 manufactured according to the present invention.
  • the pressure sensor 110 includes a diaphragm layer 140 that spans a void 170 formed in substrate 120.
  • the void 170 may optionally be sealed on the side of the substrate 120 opposite the diaphragm layer 140 by any suitable sealing mechanism, e.g., a layer of bonded glass, silicon, etc.
  • the sensor 110 includes piezoresistive transducer elements 150 that change resistivity in response to mechanical strain in the diaphragm layer 140 caused by pressure changes relative to the pressure within the void 170.
  • the extent of any deflection is dependent on the magnitude of the pressure differential on both sides of the diaphragm layer 140.
  • the pressure-dependent stress in the diaphragm layer 140 changes the electrical resistance of the transducer elements 150, a property that is easily measured with simple electronics.
  • FIG. 4 A and 4B depict a cross-sectional and a top view of a piezoelectric resonant device 210 also manufactured according to the present invention.
  • the device 210 includes a diaphragm layer 240 that can be driven into mechanical oscillation by, e.g., applying an electric signal to a central circular piezoelectric capacitor 250a (defined by the upper electrically conductive layer 252a).
  • the outer donut piezoelectric capacitor 250b (defined by the upper electrically conductive layer 252b) can act as a sensor whereby the output voltage is dependent on deflection of the diaphragm layer 240.
  • the voltages can be applied to the different capacitors 250a and 250b using electrical contacts 258a and 258b.
  • the central and outer capacitors 250a and 250b can be operated as an actuator and a sensor pair coupled by the mechanical diaphragm layer 240 to provide the elements needed for a resonant feedback loop.
  • the conductive layers 252a and 252b are preferably configured to efficiently excite the fundamental vibration mode of the diaphragm layer 240 suspended over the void 270. In use, an appropriate signal amplifier would be placed in communication with the capacitors such that the electrical signature on the sensing element is amplified and applied to the actuating element.
  • FIG. 5A and 5B depict a cross-sectional and a top view of a piezoelectric gas and/or liquid pump that can be manufactured according to the present invention.
  • a similar arrangement of the chambers and connecting channels may be found in, e.g., U.S. Patent No. 5,466,932 (Young et al.), although the construction differs according to the methods of the present invention.
  • the pump 310 can be manufactured using sacrificial material in selected areas as described above to suspend portions of the diaphragm layer 340 above the substrate 320.
  • the pump consists of two valves 316a and 316b on either side of a differential volume chamber 318.
  • the electrode configuration for the valves 316a/316b and chamber 318 are similar to those used in connection with the circular resonant device of Figures 4 A and 4B. All lower electrodes are preferably connected to ground.
  • the various portions of the diaphragm layer 340 can be actuated by simultaneously applying opposite polarity voltage levels to the inner and outer upper electrodes 352a and 352b.
  • the diaphragm layer above the chamber 318 can be depressed or moved toward the substrate 320 by applying a voltage other than ground to the central electrode 352a and voltage of the opposite polarity to the outer electrode 352b.
  • valves 316a and 316b can be actuated by applying voltages to their respective central and outer electrodes.
  • the pump 310 operates by flowing liquid or gas from one flow channel to the other.
  • Appropriate plumbing ports would preferably be made at the back surface 324 of the substrate 320.
  • Fluid pumping may be accomplished by opening the inlet valve 316a, forcing the diaphragm layer 340 in the chamber 318 up (away from the substrate 320), and closing the outlet valve 316b. Once these conditions have been established, pumping can begin by closing the inlet valve 316a, opening outlet valve 316b and reducing the volume of chamber 318. With the volume of chamber 318 reduced, the outlet valve 316b is closed and inlet valve 316a is opened. Increasing the volume of the chamber 318 then draws fluid into the chamber 318.
  • the inlet valve 316a With fluid in the chamber 318, the inlet valve 316a can be closed and outlet valve 316b opened, followed by reducing the volume of chamber 318 to force the fluid therein to exit through open outlet valve 316b. Outlet valve 316b can then be closed, followed by opening of inlet valve 316a and expansion of chamber 318 to draw more fluid into the chamber 318. The cycle then continues until the desired amount of fluid has been pumped.
  • the efficiency of the valves might be enhanced by incorporating an electrostatic clamping mechanism.

Landscapes

  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Micromachines (AREA)

Abstract

La présente invention concerne des dispositifs microélectriques, des ensembles substrats à partir desquels on peut fabriquer ces dispositifs, et des procédés de fabrication de ces dispositifs. Cette invention associe les avantages de processus classiques de micro-usinage de volume et de surface utilisant une couche sacrificielle pour créer une technique de système mécanique microélectrique intégré (MEMS) caractérisé par des performances supérieures, un haut rendement, et une tolérance de fabrication. Les dispositifs fabriqués selon cette invention sont, entre autres, des capteurs de pression, des capteurs de vibration, des accéléromètres, des pompes à gaz ou à liquides, des dispositifs résonnants, et des détecteurs infrarouges.
EP00945011A 1999-06-29 2000-06-29 Dispositifs microelectriques et leurs procedes de fabrication Withdrawn EP1196349A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US14141399P 1999-06-29 1999-06-29
US141413P 1999-06-29
PCT/US2000/017988 WO2001000523A1 (fr) 1999-06-29 2000-06-29 Dispositifs microelectriques et leurs procedes de fabrication

Publications (1)

Publication Number Publication Date
EP1196349A1 true EP1196349A1 (fr) 2002-04-17

Family

ID=22495586

Family Applications (1)

Application Number Title Priority Date Filing Date
EP00945011A Withdrawn EP1196349A1 (fr) 1999-06-29 2000-06-29 Dispositifs microelectriques et leurs procedes de fabrication

Country Status (4)

Country Link
EP (1) EP1196349A1 (fr)
AU (1) AU5901100A (fr)
CA (1) CA2377189A1 (fr)
WO (1) WO2001000523A1 (fr)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6816301B1 (en) 1999-06-29 2004-11-09 Regents Of The University Of Minnesota Micro-electromechanical devices and methods of manufacture
EP1370877A4 (fr) * 2001-02-23 2007-01-03 Water Corp Appareil mesurer les vibrations
US7867757B2 (en) 2001-12-28 2011-01-11 Norchip As Fluid manipulation in a microfabricated reaction chamber systems
GB2383546B (en) * 2001-12-28 2006-03-01 Norchip As Fluid manipulation in a microfabricated reaction chamber system
DE10320357B4 (de) * 2003-05-07 2010-05-12 Perkinelmer Optoelectronics Gmbh & Co.Kg Strahlungssensor, Wafer, Sensorarray und Sensormodul
US7181281B1 (en) 2003-10-08 2007-02-20 Pacesetter, Inc. ICD using MEMS for optimal therapy
GB2453104B (en) * 2007-09-19 2012-04-25 Wolfson Microelectronics Plc Mems device and process
GB2452941B (en) 2007-09-19 2012-04-11 Wolfson Microelectronics Plc Mems device and process

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4784721A (en) * 1988-02-22 1988-11-15 Honeywell Inc. Integrated thin-film diaphragm; backside etch
JPH0233974A (ja) * 1988-07-22 1990-02-05 Mitsubishi Electric Corp 圧力変換素子の製造方法
US5209119A (en) * 1990-12-12 1993-05-11 Regents Of The University Of Minnesota Microdevice for sensing a force
DE4227819C2 (de) * 1991-08-22 1996-10-17 Yamatake Honeywell Co Ltd Kapazitiver Drucksensor
US5332469A (en) * 1992-11-12 1994-07-26 Ford Motor Company Capacitive surface micromachined differential pressure sensor
JPH08236784A (ja) * 1995-02-23 1996-09-13 Tokai Rika Co Ltd 加速度センサ及びその製造方法
JP3536516B2 (ja) * 1996-02-28 2004-06-14 株式会社ニコン フローティング構造の形成方法

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO0100523A1 *

Also Published As

Publication number Publication date
WO2001000523A1 (fr) 2001-01-04
CA2377189A1 (fr) 2001-01-04
WO2001000523A9 (fr) 2002-07-25
AU5901100A (en) 2001-01-31

Similar Documents

Publication Publication Date Title
US6816301B1 (en) Micro-electromechanical devices and methods of manufacture
Esashi et al. Vacuum-sealed silicon micromachined pressure sensors
JP4871513B2 (ja) 薄く形成されたカンチレバー構造を備えた微小機械装置及び関連の方法
US5726480A (en) Etchants for use in micromachining of CMOS Microaccelerometers and microelectromechanical devices and method of making the same
EP1522521B1 (fr) Capteur capacitif
EP1359402B1 (fr) Capteur de pression
US7998777B1 (en) Method for fabricating a sensor
EP1920229B1 (fr) Capteurs de pression et procedes de realisation
JP5891571B2 (ja) Ｍｅｍｓ圧力センサ装置及びその作製方法
EP2339357B1 (fr) Procédé de fabrication d'un capteur
US7541214B2 (en) Micro-electro mechanical device made from mono-crystalline silicon and method of manufacture therefore
WO1996023229A9 (fr) Reactifs d'attaque s'utilisant dans le micro-usinage de micro-accelerometres a cmos et de dispositifs microelectromecaniques et leur procede de fabrication
JP2012506616A (ja) ウェーハレベルでパッケージングされたｍｅｍｓデバイス
WO2001000523A1 (fr) Dispositifs microelectriques et leurs procedes de fabrication
Mirza Wafer-level packaging technology for MEMS
Eaton et al. CMOS-compatible surface-micromachined pressure sensor for aqueous ultrasonic application
KR101055604B1 (ko) 박막형 압전소자 및 그 제조방법
Beeby Printed thick-film mechanical microsystems (MEMS)
Gogoi et al. Force balanced micromachined pressure sensors
Mokwa Advanced sensors and microsystems on SOI
Hao et al. Fabrication of atmospheric pressure sensors using AU-AU bonding techniques for human activity monitoring
Tang et al. A two-gap capacitive structure for high aspect-ratio capacitive sensor arrays
Zou et al. CoMSaT: a single-chip fabrication technique for three-dimensional integrated fluid systems
JP2003004566A (ja) 静電容量型圧力センサ及びその製造方法
Benecke Micromechanical sensors

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20020107

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT

AX Request for extension of the european patent

Free format text: AL;LT;LV;MK;RO;SI

17Q First examination report despatched

Effective date: 20050623

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20051104