Abstract: A microelectromechanical systems device having support structures formed of sacrificial material that is selectively diffused with a dopant material or formed of a selectively oxidized metal sacrificial material. The microelectromechanical systems device includes a substrate having an electrode formed thereon. Another electrode is separated from the first electrode by a cavity and forms a movable layer, which is supported by support structures formed of a diffused or oxidized sacrificial material.

Abstract: A method of forming a MEMS device provides a wafer having a base with a conductive portion. The wafer also has an intermediate conductive layer. After it provides the wafer, the method adds a diaphragm layer to the wafer. The method removes at least a portion of the intermediate conductive layer to form a cavity between the diaphragm layer and the base. At least a portion of the diaphragm layer is movable relative to the base. After it forms the cavity, the method seals the cavity.

Abstract: Techniques and devices are described to use spatially-varying curvature information of a layered structure to determine stresses at each location with non-local contributions from other locations of the structure. For example, a local contribution to stresses at a selected location on a layered structure formed on a substrate is determined from curvature changes at the selected location and a non-local contribution to the stresses at the selected location is also determined from curvature changes at all locations across the layered structure. Next, the local contribution and the non-local contribution are combined to determine the total stresses at the selected location. Techniques and devices for determining a misfit strain between a film and a substrate on which the film is deposited are also described.

Abstract: A microelectronic pressure sensor comprises a MOSFET transistor adapted with a mobile gate and a cavity between the mobile gate and a substrate. The sensor includes a gate actuator configured to move mobile gate in response to a pressure being exercised. A fingerprint recognition system includes a matrix of such sensors.

Abstract: A method of forming a metal-oxide-semiconductor (MOS) transistor device is disclosed. A semiconductor substrate is prepared first, and the semiconductor substrate has a gate structure, a source region and a drain region. Subsequently, a stress buffer layer is formed on the semiconductor substrate, and covers the gate structure, the source region and the drain region. Thereafter, a stressed cap layer is formed on the stress buffer layer, and a tensile stress value of the stressed cap layer is higher than a tensile stress value of the stress buffer layer. Since the stress buffer layer can prevent the stressed cap layer from breaking, the MOS transistor device can be covered by a stressed cap layer having an extremely high tensile stress value in the present invention.

Abstract: A gas-sensitive field-effect transistor may be formed from a substrate with a gas-sensitive layer and a transistor processed separately and then assembled. The substrate may be patterned to form spacers by which the height of an air gap between the transistor and the sensitive layer may be adjustable to a relatively precise degree. Formation of the spacers can be achieved by patterning the substrate using material-removal techniques. The height of the spacers may be adjusted in the layer thickness of the gas-sensitive layer and for the transistor fabricated using a CMOS process. Suitable techniques for producing recesses between the spacers include, for example, polishing, cutting, sandblasting, lithographic dry etching, or wet-chemical etching. Suitable materials for the substrate may include, for example, glass, ceramic, aluminum oxide, silicon, or a dimensionally stable polymer.

Abstract: Noise occurring in a circuit is more accurately detected. A low-pass filter (11) is connected to a power supply line for a power supply terminal (VDD), and noise in the power supply line is removed to generate and output a referential voltage (V0). A high-pass filter (12) is connected to a power supply line, and a noise signal in the power supply line is passed with the referential voltage (V0) as a reference. A high-pass filter (13) is connected to a ground line for a ground terminal (GND), and a noise signal in the ground line is passed based on the referential voltage (V0) as a reference. A reference voltage generation circuit (14) generates and outputs a reference voltage (Vref) based on the referential voltage (V0) as a reference. Comparison circuits (CMP1 and CMP2) respectively compare output voltage of the high-pass filters (12 and 13) and the reference voltage (Vref).

Abstract: Semiconductor device comprising at least: one substrate, a transistor comprising at least one source region, one drain region, one channel and one gate, a planar layer based on at least one piezoelectric material, resting at least on the gate and capable of inducing at least mechanical strain on the transistor channel, in a direction that is substantially perpendicular to the plane of a face of the piezoelectric layer situated on the gate side, piezoelectric layer being arranged between two biasing electrodes, one of the two biasing electrodes being formed by a first layer based on at least one electrically conductive material such that the piezoelectric layer is arranged between this first conductive layer and the gate of the transistor.

Abstract: A method for fabricating a MEMS device having a fixing part fixed to a substrate, a connecting part, a driving part, a driving electrode, and contact parts, includes patterning the driving electrode on the substrate; forming an insulation layer on the substrate; patterning the insulation layer and etching a fixing region and a contact region of the insulation layer; forming a metal layer over the substrate; planarizing the metal layer until the insulation layer is exposed; forming a sacrificial layer on the substrate; patterning the sacrificial layer to form an opening exposing a portion of the insulation layer and the metal layer in the fixing region; forming a MEMS structure layer on the sacrificial layer to partially fill the opening, thereby forming sidewalls therein; and selectively removing a portion of the sacrificial layer by etching so that a portion of the sacrificial layer remains in the fixing region.

Abstract: An alternative sensing circuit for a micro-electro-mechanical system (MEMS) microphone and a sensing method thereof are provided. The sensing circuit reads out output signals of an MEMS electret microphone or an MEMS condenser microphone. In considering different operating requirements of the different MEMS microphones, for example, low power consumption for the MEMS electret condenser microphone or high sensitivity for the MEMS condenser microphone, the manner of using two kinds of MEMS microphone sensing components in one circuit can significantly increase the flexibility of using the MEMS microphone and can be applied to the application or design of a condenser sensing component.

Abstract: A micromechanical device comprising one or more electronically movable structure sets comprising for each set a first electrode supported on a substrate and a second electrode supported substantially parallel from said first electrode. Said second electrode is movable with respect to said first electrode whereby an electric potential applied between said first and second electrodes causing said second electrode to move relative to said first electrode a distance X, (X), where X is a nonlinear function of said potential, (V). Means are provided for linearizing the relationship between V and X.

Abstract: A MEMS microphone is fabricated into an integrated physical device which also comprises a solar cell. The solar cell provides power to the MEMS microphone, and may do so with use of a capacitor, which may also be incorporated into the device, and serves to provide power to the MEMS microphone when the solar cell is unable to do so (e.g., at night). A wireless transmitter and antenna may also be incorporated into the device, in order to transmit acoustic data which has been captured by the MEMS microphone. In one embodiment of the invention, the MEMS microphone comprises a fixed backplate and a diaphragm, and the solar cell is advantageously comprised in the diaphragm thereof.

Abstract: A circuit device is provided which can be manufactured at reduced costs and which is highly reliable. The circuit device includes a Sensor area formed on part of a semiconductor substrate, a circuit area formed around the sensor area on the semiconductor substrate to process electric signals produced at the sensor area, and a sealring disposed between the sensor area and the circuit area. The sealring is disposed between the outer periphery of the sensor area and the inner periphery of the circuit area to surround the sensor area. In the circuit device, the sealring prevents water or moisture from infiltrating from the sensor area into the circuit area.

Abstract: A plurality of excitation elements, each including an IDT and a piezoelectric film, for exciting, respectively, surface acoustic waves, each having a unique center frequency, are formed on one end of a non-piezoelectric substrate, a plurality of receiving elements, each including an IDT and a piezoelectric film, for receiving, respectively, surface acoustic waves, each having a unique center frequency, are formed on the other end of the non-piezoelectric substrate to face the excitation elements, respectively, the center frequencies of the IDTs of the facing excitation element and receiving element are equal, the center frequencies of the IDTs of the excitation elements next to each other are different, and surface acoustic waves are propagated across the non-piezoelectric substrate, between the facing excitation elements and receiving elements so as to detect the position of an object in contact with the non-piezoelectric substrate, based on received results in the receiving elements.

Abstract: A device for manufacturing a capacitive pressure measurement includes an insulated base electrode, a mechanically deflectable counterelectrode composed of a layer made of at least one of a monocrystalline and polycrystalline semiconductor material, a contact arrangement for electrically connecting the electrodes, and at least one semiconductor component, all integrated onto a semiconductor substrate. The connection for the base electrode is formed by an electrically insulated conductive polycrystalline semiconductor layer. The method for manufactured the device includes the step of arranging a conductive polycrystalline semiconductor layer between two insulating layers on the semiconductor substrate for forming a base electrode.

Abstract: There are many inventions described and illustrated herein. In one aspect, the present invention is directed to a MEMS device, and technique of fabricating or manufacturing a MEMS device having mechanical structures and anchors to secure the mechanical structures to the substrate. The anchors of the present invention are comprised of a material that is relatively unaffected by the release processes of the mechanical structures. In this regard, the etch release process are selective or preferential to the material(s) securing the mechanical structures in relation to the material comprising the anchors. Moreover, the anchors of the present invention are secured to the substrate in such a manner that removal of the insulation layer has little to no affect on the anchoring of the mechanical structures to the substrate.

Abstract: Complementary metal oxide semiconductor transistors are formed on a silicon substrate. The substrate has a {100} crystallographic orientation. The transistors are formed on the substrate so that current flows in the channels of the transistors are parallel to the <100> direction. Additionally, longitudinal tensile stress is applied to the channels.

Abstract: A MOS transistor with a deformable gate formed in a semiconductor substrate, including source and drain areas separated by a channel area extending in a first direction from the source to the drain and in a second direction perpendicular to the first one, a conductive gate beam placed at least above the channel area extending in the second direction between bearing points placed on the substrate on each side of the channel area, and such that the surface of the channel area is hollow and has a shape similar to that of the gate beam when said beam is in maximum deflection towards the channel area.

Abstract: A capacitive dynamic quantity sensor whose size is small and whose reliability and mass productivity are high is provided. In order to realize signal transmission from a lower electrode to an upper electrode, silicon columns which are electrically isolated from one another but not mechanically isolated from one another are formed to connect both electrodes.

Abstract: Field effect devices having a drain controlled via a nanotube switching element. Under one embodiment, a field effect device includes a source region and a drain region of a first semiconductor type and a channel region disposed therebetween of a second semiconductor type. The source region is connected to a corresponding terminal. A gate structure is disposed over the channel region and connected to a corresponding terminal. A nanotube switching element is responsive to a first control terminal and a second control terminal and is electrically positioned in series between the drain region and a terminal corresponding to the drain region. The nanotube switching element is electromechanically operable to one of an open and closed state to thereby open or close an electrical communication path between the drain region and its corresponding terminal.

Abstract: A physical quantity sensor includes: a semiconductor substrate; a cavity disposed in the substrate and extending in a horizontal direction of the substrate; a groove disposed on the substrate and reaching the cavity; a movable portion separated by the cavity and the groove so that the movable portion is movably supported on the substrate; and an insulation layer disposed on a bottom of the movable portion so that the insulation layer provides a roof of the cavity.

Abstract: A method for producing probes for atomic force microscopy comprises producing, on a surface of one side of a semiconductor substrate, one or more moulds for the production of one or more probe tips. One or more probe configurations and at least one set of a probe tip and a cantilever are also produced on the side of the substrate, wherein each configuration comprises a contact region for attachment of a holder. The surface area of each contact region is smaller in size than the surface area of the holder. The method further includes attaching one or more holders to the contact region(s), and releasing the probe configuration and the holder from the substrate by under-etching the probe configuration from the side of the substrate on which the probe configuration is produced.

Abstract: A method for manufacturing a semiconductor device includes a step of forming a first groove in a first insulating film, forming a conductive film in the first groove, a step of selectively forming a second insulating film on the conductive film and the first insulating film, a step of forming a second groove by removing part of the conductive film using the second insulating film as a mask, the second groove being formed so as to form a connecting portion of the conductive film under the second insulating film and form a first wiring layer by forming the connecting portion with a bottom of the first groove integrally with each other as one unit.

Abstract: An integrated circuit is formed on a non-planar substrate. The integrated circuit is formed over a plurality of layers. Chemical or physical changes in the microstructure of the substrate cause the bending of the substrate, in one or more propagation directions.

Abstract: A sensor chip for defining an exposed molding region is disclosed. The sensor chip includes a semiconductor chip and a metal dam bar protruding from the active surface of the semiconductor chip. The active surface of the semiconductor chip includes a sensing region and at least one bonding pad is disposed on the active surface. The metal dam bar separates the sensing region and the bonding pad to prevent contamination of the sensing region by the mold flash. Preferably, a step is formed on the periphery of the active surface of the semiconductor chip, such that the semiconductor chip includes a T-shaped profile. Additionally, the metal dam bar is extended to the step to form an enclosed ring thereby effectively defining an exposed molding region that contains the sensing region.

Abstract: Method and structure for optimizing dual damascene patterning with polymeric dielectric materials are disclosed. Certain embodiments of the invention comprise polymeric sacrificial light absorbing materials (“polymer SLAM”) functionalized to have a controllable solubility switch wherein such polymeric materials have substantially the same etch rate as conventionally utilized polymeric dielectric materials, and subsequent to chemical modification of solubility-modifying protecting groups comprising the SLAM materials by thermal treatment or in-situ generation of an acid, such SLAM materials become soluble in weak bases, such as those conventionally utilized to remove materials in lithography treatments.

Abstract: A method for manufacturing a flexible MEMS transducer includes forming a sacrificial layer on a flexible substrate, sequentially depositing a membrane layer, a lower electrode layer, an active layer, and an upper electrode layer on the sacrificial layer by PECVD, sequentially patterning the upper electrode layer, the active layer, and the lower electrode layer, depositing an upper protective layer to cover the upper electrode layer, the lower electrode layer, and the active layer, patterning the upper protective layer to be connected to the lower electrode layer and the upper electrode layer, and then depositing a connecting pad layer and patterning the connecting pad layer to form a first connecting pad to be connected to the lower electrode layer and a second connecting pad to be connected to the upper electrode layer; and patterning the membrane layer to expose the sacrificial layer and removing the sacrificial layer.

Abstract: In a semiconductor sensor having a membrane structure, the destruction of the membrane caused by the expansion or contraction of a fluid within a hollow part formed under the membrane while the sensor is in use is prevented. A semiconductor sensor 10 comprising a substrate 30 and a membrane 20 formed on the top surface thereof, in which the bottom of the substrate 30 and a mounting surface 50 on which the sensor 10 is mounted are bonded, has pressure difference adjusting means 22a to 22c for eliminating the difference in pressure of a fluid between an inside and an outside of a hollow part 34 while the sensor is in use.

Abstract: A vertically integrated structure includes a micro-electromechanical system (MEMS) and a chip for delivering signals to the MEMS. The structure includes a metal stud connecting a surface of the chip and the MEMS; the MEMS has an anchor portion having a conducting pad on an underside thereof contacting the metal stud. The MEMS is spaced from the chip by a distance corresponding to a height of the metal stud, and the MEMS includes a doped region in contact with the conducting pad. In particular, the MEMS may include a cantilever structure, with the end portion including a tip extending in the vertical direction. A support structure (e.g. of polyimide) may surround the metal stud and contact both the underside of the MEMS and the surface of the chip. A temporary carrier plate is used to facilitate handling of the MEMS and alignment to the chip.

Abstract: MEMS devices are provided that are capable of movement due to a flexible portion formed of unique materials for this purpose. The MEMS device can have a flexible portion formed of a nitride or oxynitride of at least one transition metal, and formed of a nitride or oxynitride of at least one metalloid or near metalloid; a flexible portion formed of a single transition metal nitride or oxynitride and in the absence of any other metal or metalloid nitrides; a flexible portion formed of one or more late transition metal nitrides or oxynitrides; a flexible portion formed of a single transition metal in nitride form, and an additional metal substantially in elemental form; or a flexible portion formed of at least one metalloid nitride or oxynitride. The MEMS devices can be any device, though preferably one with a flexible portion such as an accelerometer, DC relay or RF switch, optical cross connect or optical switch, or micromirror arrays for direct view and projection displays. The flexible portion (e.g.

Abstract: Two piezoelectric thin films each sandwiched between a main electrode layer and an opposite electrode layer are laminated in pairs so as to form a thin film piezoelectric element. An electrode leading area has a region in which the main electrode layer partially projects from the piezoelectric thin film, and another region in which only an insulating layer is formed on a part of the opposite electrode layer. At least one of a first opening formed through the insulating layer in the former region and a second opening formed through the insulating layer in the latter region is provided. A connection wiring for connecting to the opposite electrode layer or the main electrode layer and leading to the surface layer is formed via the opening.

Abstract: Micromechanical devices are provided that are capable of movement due to a flexible portion. The micromechanical device can have a flexible portion formed of a nitride of preferably an element from groups 3A to 6A of the periodic table (preferably from the first two rows of these groups) and a late transition metal (preferably from groups 8B or 1B of the periodic table). The micromechanical devices can be any device, particularly MEMS sensors or actuators preferably having a flexible portion such as an accelerometer, DC relay or RF switch, optical cross connect or optical switch, or a micromirror part of an array for direct view and projection displays. The flexible portion is preferably formed by sputtering a target having a group 8B or 1B element and a group 3A to 6A element. The target can have other major constituents or impurities (e.g. additional group 3A to 6A element(s)). The target is reactively sputtered in a nitrogen ambient so as to result in a sputtered hinge.

Abstract: A capacitor for use within a microelectronic product employs a first capacitor plate layer that includes a first series of horizontally separated and interconnected tines. A capacitor dielectric layer separates the first capacitor plate layer from a second capacitor plate layer. The second capacitor plate layer includes a second series of horizontally separated and interconnected tines horizontally interdigitated with the first series of horizontally separated and interconnected tines. The capacitor is formed employing a self-aligned method and the capacitor dielectric layer is formed in a serpentine shape.

Abstract: A Micro Electro-Mechanical Systems (MEMS) thermal switch. The switch includes a FET having a source and drain in a substrate and a beam isolated from the substrate. The beam is positioned over the source and the drain and spaced by a predefined gap. When the thermal set point is reached, the beam moves to electrically connect the source to the drain.

Abstract: A method of fabricating an integrated circuit that includes a microelectromechanical (MEMS) device. The method includes forming a MEMS device on a substrate and forming an integrated circuit. The method further includes coupling the substrate to the integrated circuit to form a sealed cavity that includes the MEMS device. The substrate and the integrated circuit are coupled together in a controlled environment to establish a controlled environment within the cavity where the MEMS device is located.

Abstract: Surface micromachined structures having a relatively thick dielectric layer and a relatively thin conductive layer bonded together.

Abstract: A basic portion layer 21 of a substrate electrode 12a connected to a projecting electrode 13 electrically and mechanically on a substrate member of ceramics. The substrate member on which the basic portion layer 21 is formed is subjected to sintering. A surface of the basic portion layer 21 in the sintered substrate member is polished. On the polished basic portion layer 21, the plating layers 22, 23 are formed, so that surface roughness of the substrate electrode 12a may be, for example, not larger than 0.1 ?mRMS. Accordingly, junction strength of an integrated circuit element mounted on a packaging substrate by a flip-chip method can be improved.

Abstract: A method of producing well-defined polycrystalline silicon regions is described, in particular for producing electrically conducting regions, in which a substrate is provided with an insulating layer and a layer of doped amorphous silicon, electromagnetic irradiation is performed using a laser source to produce the electrically conducting regions, and a shadow mask is positioned between the laser source and the substrate having the layer for definition of the contours of the electrically conducting regions.

Abstract: A semiconductor component for a semiconductor substrate, in which a first section and a second section are provided, and in which the pore structure of the first section differs from the pore structure of the second section.

Abstract: A flexible wireless MEMS microphone includes a substrate of a flexible polymeric material, a flexible MEMS transducer structure formed on the substrate by PECVD, an antenna printed on the substrate for communicating with an outside source, a wire and interface circuit embedded in the substrate to electrically connect the flexible MEMS transducer and the antenna, a flexible battery layer electrically connected to the substrate for supplying power to the MEMS transducer, and a flexible bluetooth module layer electrically connected to the battery layer. The flexible MEMS transducer includes a flexible substrate, a membrane layer deposited on the substrate, a lower electrode layer formed on the membrane layer, an active layer formed by depositing a piezopolymer on the lower electrode layer, an upper electrode layer formed on the active layer, and a first and a second connecting pad electrically connected to the lower and upper electrode layers, respectively.

Abstract: A method of deforming a pattern comprising the steps of: forming, over a substrate, a layered-structure with an upper surface including at least one selected region and at least a re-flow stopper groove, wherein the re-flow stopper groove extends outside the selected region and separate from the selected region; selectively forming at least one pattern on the selected region; and causing a re-flow of the pattern, wherein a part of an outwardly re-flowed pattern is flowed into the re-flow stopper groove, and then an outward re-flow of the pattern is restricted by the re-flow stopper groove extending outside of the pattern, thereby to form a deformed pattern with at least an outside edge part defined by an outside edge of the re-flow stopper groove.

Abstract: Tensile or compressive stress may be added in one or more selected locations to the biaxial residual stress existing in the channel of a semiconductor device, such as a MOSFET. The periphery of the active area containing the channel is modified by following layout procedures that result in forming outward protrusions of or inward depressions in the periphery of the active area and its surrounding shallow trench isolation during generally otherwise conventional fabrication of the device.

Abstract: A method of reducing package stress includes placing matched components of an op-amp substantially in a region of a die having the least stress gradients. The region is located in the center of the die. Further, the center is the common centroid of the die. The matched components are the current mirror input stages of the op-amp. In one embodiment, a semiconductor configuration includes a die having a region with the least stress gradients, and an op-amp containing matched components that are located substantially in the region.

Abstract: A Microelectromechanical (MEMS) device and method of fabrication that can minimize derailing of an actuable element of the MEMS device during fabrication can include a MEMS actuator to selectively generate displacement forces to displace an actuable element along a path between sidewalls of a channel. The sidewalls can have stops formed therein that can interact with surfaces on the actuable element to limit displacement of the actuable element during fabrication. One of the sidewalls can be indented to form the stops and the actuable element can have an arm portion that extends between the stops. The sidewalls can be offset to form the stops on spaced apart faces on opposite sides of the channel and the actuable element can be offset between the spaced apart faces to form offset faces in an opposing relationship with the spaced apart faces on the sidewalls. In addition, the actuable element and the sidewalls may be so shaped as to maintain a generally constant width between them.

Abstract: Method and structure for optimizing dual damascene patterning with polymeric dielectric materials are disclosed. Certain embodiments of the invention comprise polymeric sacrificial light absorbing materials (“polymer SLAM”) functionalized to have a controllable solubility switch wherein such polymeric materials have substantially the same etch rate as conventionally utilized polymeric dielectric materials, and subsequent to chemical modification of solubility-modifying protecting groups comprising the SLAM materials by thermal treatment or in-situ generation of an acid, such SLAM materials become soluble in weak bases, such as those conventionally utilized to remove materials in lithography treatments.

Abstract: A method is described for producing surface micromechanical structures having a high aspect ratio, a sacrificial layer being provided between a substrate and a function layer, trenches being provided by a plasma etching process in the function layer, at least some of these trenches exposing surface regions of the sacrificial layer. To increase the aspect ratio of the trenches, an additional layer is deposited on the side walls of the trenches in at least some sections, but not on the exposed surface regions of the sacrificial layer. In addition, a sensor is described, in particular an acceleration sensor or a rotational rate sensor.

Abstract: A Microelectromechanical (MEMS) device that can minimize the effects of fabrication tolerances on the operation of the device can include a MEMS electromagnetic actuator to selectively generate displacement forces to displace an actuable element along a path. A cantilever can apply an opposing force to the actuable element to control the amount of displacement. Coil ends of the actuator can be shaped to vary a gap distance between the coil ends, and/or the magnetic portion of the actuable element may be shaped, so as to vary the force applied to the actuable element along the displacement axis. One or more pins located in the deflection path of the cantilever can contact the cantilever at one or more points so as to change the bending resistance of the cantilever. The cross-section of the cantilever can also be varied along its length so as to change the bending resistance of the cantilever.

Abstract: A vertically integrated structure includes a micro-electromechanical system (MEMS) and a chip for delivering signals to the MEMS. The MEMS has an anchor portion having a conductor therethrough, by which it is connected to a substrate. The chip is attached to the MEMS substrate in a direction normal to the substrate surface, so as to make a conductive path from the chip to the MEMS. The chip may be attached by bonding the conductor to C4 metal pads formed on the chip, or by bonding the conductor to metal studs on the chip. The MEMS substrate may be thinned before attachment to the chip, or may be removed from the underside of the MEMS. A temporary carrier plate is used to facilitate handling of the MEMS and alignment to the chip.

Abstract: A structure having a first part and at least one second part. The second part is electrically insulated from the first part and the parts are formed in the same wafer of a material. The first and second parts have the same thickness, extend in the same plane and have at least one mutually adjacent edge. The adjacent edges are separated by a spacing. In addition there is at least one joint of insulating material arranged in the spacing to make the first and second parts integral. The structure may be used for sensors and isolated circuits.

Abstract: A surface acoustic wave device includes a piezoelectric substrate and interdigital electrode portions disposed on the piezoelectric substrate. A functional film including at least one of a silicon nitride film, a silicon oxide film, and a silicon oxide nitride film is formed on the piezoelectric substrate having the interdigital electrode portions such that the functional film is formed on at least a portion of the interdigital electrode portions by an electron cyclotron resonance sputtering method.