Abstract: Electrostatic microactuators are described in which stationary electrodes (4) and movable electrodes (3) mounted on flexures (6) have relative locations and mechanical properties such that non-linear pull-in/pull-out behavior is displayed when a voltage is applied between the stationary electrodes (4) and the electrodes do not come into contact. Larger electrostatic forces and longer travel ranges are achievable with lower applied voltages than typical microactuators. Further advantageous properties are obtained with the application of time-varying voltages with peak values exceeding the pull-in voltage and also at frequencies near a resonant frequency of the device. Several applications are described.

Abstract: The present invention relates to batteries that can be activated by liquid. The battery with porous material is suitable for disposable healthcare test kits, bioMEMS (bio Micro Electro Mechanical Systems) and biosystems such as DNA chips, lab-on-a-chip or micro fluidics and can be easily integrated with disposable devices/systems.

Abstract: An acceleration sensitive switch arrangement (208) includes an acceleration sensitive variable capacitor (200), a detection circuit (202) for detecting a capacitance value of the variable capacitor (200), and a switching circuit (204) responsive to a comparison between the detected capacitance and a threshold value.

Abstract: Microbatteries based on liquid electrolyte are provided suitable for disposable microsystems including MEMS and bioMEMS. Systems using disposable and on-demand microbattery are also provided. Microbattery consists of a substrate, an anode supplying electrons when the anode contact to an electrolyte, a sealed liquid pocket including liquid mixture of an electrolyte and a cathode, a pressing means to generate pressure in said sealed liquid pocket, breaking means that is easily torn or removed by the pressure generated in said, liquid pocket, conducting electron collectors collecting electron to assist cathodic reaction and a cavity. Surface tension drives said liquid mixture into said cavity after tearing said breaking means, then electro-chemical reaction occurs to activate the microbattery. Water or blood activated microbattery is also provided for bioMEMS.

Abstract: A comb structure in which a magnetic force, which is generated between a pair of intermeshed combs by applying a magnetic flux thereto, is constant with respect to the relative motion between the combs, is provided. Also, an actuator and an inertia sensor both using the comb structure are provided. The comb structure includes a pair of magnetic combs, a magnetic flux guide for magnetically connecting the pair of combs, a coil wound around an arbitrary portion of the magnetic flux guide, and a power supply connected to the coil. The pair of magnetic combs intermeshed with each other having a gap S therebetween are connected to each other by the magnetic flux guide, such that they are driven by receiving a magnetic field from the coil. The coil is supposed to generate a magnetic field under the influence of a current provided from the power supply.

Abstract: A telephone system is provided with a receiver equipped to enable a hearing-impair person to receive a telephone call through bone-conduction and air-conduction hearing.

Abstract: A 3-dimensional comb structure using an electrical force, and an inertial detection sensor and an actuator both using the 3-dimensional comb structure are provided. In the 3-dimensional comb structure, a suspension structure, which is an inertia body, is separated a predetermined height from a substrate, maintaining the predetermined height from the substrate. A movable comb, which has at least one movable comb finger, protrudes perpendicularly from the suspension structure. A fixed comb, which has at least one fixed comb finger, protrudes perpendicularly from the substrate, in mesh with the movable comb. The 3-dimensional comb structure is driven by a voltage provided from a power supply unit which is connected to the movable comb and the fixed comb.

Abstract: A multilayered wafer with a thick sacrificial layer, which is obtained by forming a sacrificial layer of oxidized porous silicon or porous silicon and growing an epitaxial polysilicon layer on the sacrificial layer, and a fabrication method thereof are provided. The multilayered wafer with a thick sacrificial layer adopts a porous silicon layer or an oxidized porous silicon layer as a sacrificial layer such that a sufficient gap can be obtained between a substrate and a suspension structure upon the manufacture of the suspension structure of a semiconductor actuator or a semiconductor inertia sensor. Also, in a fabrication method of the wafer according to the present invention, a p+-type or n+-type wafer doped at a high concentration is prepared for, and then a thick porous silicon layer can be obtained simply by anodic-bonding the surface of the wafer. Also, when polysilicon is grown on a porous silicon layer by an epitaxial process, it is grown faster than when single crystal silicon is grown.

Abstract: A microactuator is provided.

Abstract: There is provided a method of adjusting the natural frequency of a dual-axis vibratory structure having: a first spring member having a lengthwise direction coinciding to a first axis direction receiving an electrostatic force; a second spring member having a lengthwise direction coinciding to a second direction perpendicular to the first axis direction and having a width narrower than that of the first spring member; and a mass portion, the method comprising the steps of: measuring the natural frequencies relative to the first axis direction of the vibratory structure and a third axis direction perpendicular to a plane formed by the first and second axes; varying the thickness of the first spring member so as to adjust the natural frequency of the third axis direction while fixing the natural frequency of the first axis direction; and repeating the measuring step and the thickness varying step until the natural frequency of the first and third axes directions are within the scope of a permissible error.

Abstract: A vibratory structure and a method for controlling the natural frequency thereof are provided. The device has at least one elastic member supported by a first support end, an inertial object which vibrates by the elastic force of the elastic member, a moving electrode coupled to the inertial object, at least one effective stiffness controlling electrode supported by a second support end, and a power supplier for applying a voltage to generate an electric force between the moving electrode and the effective stiffness controlling electrode. This vibratory structure can contribute to controlling and improving the performance of a sensor, an actuator or a gyroscope, which employs the vibratory structure.

Abstract: A vibratory structure and a method for controlling the natural frequency thereof are provided. The vibratory structure has an elastic member one end portion of which is fixed to a first support end, an inertial object for vibrating by the elastic force of the elastic member, a moving electrode attached integrally to the inertial object, an effective stiffness controlling electrode fixed to a second support end, and a power supplier for generating electric force between the moving electrode and the effective stiffness controlling electrode. The moving electrode and the effective stiffness controlling electrode are formed into a predetermined shape, so that the electric force varies linearly according to the displacement of the inertial object. Thus, the natural frequency of the vibratory structure is controlled by changing the voltage applied across the moving electrode and the effective stiffness controlling electrode.

Abstract: Inkjet printing head utilizing a shear mode and, simultaneously, tension and compression modes for effectively preventing damage to the contact interface of the piezoelectric device, includes at least one piezoelectric device installed on a pressure channel, having shear, tension and compression modes and combined with the upper and lower plates of the channel, the piezoelectric device having electrodes supplying an electrical field thereof.