The integration of MEMS, SAW devices and required microelectronics and conformal antenna to realize a programmable wireless accelerometer is presented in this paper. This unique combination of technologies results in a novel accelerometer that can be remotely sensed by a microwave system with the advantage of no power requirements at the sensor site. The microaccelerometer presented is simple in construction and easy to manufacture with existing silicon micromachining techniques. The relatively small size of the sensor makes it an ideal conformal sensor. The accelerometer finds application as air bag deployment sensors, vibration sensors for noise control, deflection and strain sensors, inertial and dimensional positioning systems, ABS/traction control, smart suspension, active roll stabilization and four wheel steering. The wireless accelerometer is very attractive to study the response of a 'dummy' in automobile crash test.

This paper describes a new method to fabricate the blazed gratings on oriented silicon by the anisotropic etching technique. Instead of making the multilevel gratings by the binary lithography or preparing the analog resist profiles by the e-beam direct-write, we propose a new sequence to obtain the blazed gratings with a continuous blaze surface. The key techniques include the oblique lapping/polishing and the time/portion control of potassium wet etching. This method has the advantages of easy facility, low cost, and large tolerance in gratings' design.

In this paper we present a novel method for selective electroplating on silicon without the need of using a continuous plating base film. Ion implantation on the polished front face of a silicon wafer is employed to induce selective seeding of electroplating. Silicon substrates have been implanted at RT with 19 keV Pd⁺ ions at several doses 7e14, 2e15, 1e16 and 1e17 ions/c,² using a metal vapor vacuum arc ion implanter. These are then electroplated under similar bath conditions using a Ni-Fe plating solution to produce permalloy films. The unimplanted regions do not get plated showing the selective nature of this seeding process. Adhesion is better for films plated on substrates implanted at higher dose. To study the effect of implanted species, a silicon wafer was implanted with self ions and plated under similar conditions. This sample showed deposition of an extremely thin film. The potential of the technique has been demonstrated by patterning 50 and 100 (mu) wide metallic structures on silicon substrate.

This paper describes the design and fabrication techniques of micro capillary columns as the main components in a microengineered gas chromatography system. The system is to be developed using silicon micromachining technology, and is designed as a flexible device consisting of four basic modules: a sample injection system, an open tubular column, a gas detector system, and an electronic circuit. Being designed in a modular structure, the system can be operated in a single and multidimensional configurations. The overall device measures 6 cm X 11 cm, making it very portable for field operation. The micromachined capillary columns are isotopically etched on silicon and sealed by Pyrex glass cover plate, measuring 125 cm long, and having rectangular shaped cross sections.

Adhesively-bonded fiber reinforced composite patches have been used extensively, over the last two decades, on Royal Australian Air Force aircraft to repair fatigue-cracked metallic aircraft components. The bonded repair to the cracked structure - crack patching - allows the restoration of strength and stiffness to the structure, as well as slowing crack growth by reducing stress intensity. However, especially for repairs to critical components the bonded repair needs continuous health monitoring to ensure structural integrity is not compromised. The ultimate goal for very demanding repair applications is to incorporate sensor, actuators and electronics in repair systems - smart repair systems - to monitor and report on the health of the repair and the repaired structure, as well as to actuate in order to prevent damage or failure of the repaired structure. The initial focus in the development of smart repair systems is on the assessment of new sensors and instrumentation which may be incorporate in bonded repair system in order to achieve on-line measurement of patch integrity and effectiveness. This application would allow the operator to move away from current costly time-based maintenance procedures toward real-time health condition monitoring of the bonded repair and the repaired structure. These systems would allow timely decisions on preventative and schedule maintenance before failure of the repair or repaired structure. To this end a 'stand-alone' data logger device, for the real-time health monitoring of bonded repaired system, which is in lose proximity to sensors on a repair is being developed. The instrumentation will measure, process and store sensor measurements during flight and then allow this data to be down loaded, after the flight, onto a PC, via remote data access.

A novel concept self-oscillator and dynamically tunable micro vibratory gyroscope, where oscillating, position- sensing and force-balancing take place on the wafer surface, has been developed. The gyroscope consists of: a grid-type planar mass which oscillates on the wafer surface; pairs of the differential capacitor type with LT shape position sense electrodes; a pair of force-balancing electrodes; oppositely placed comb-drive and comb-sensor for mass self-oscillation; fish hook shape springs to match the first and second modes with the mass oscillating and position sensing modes, respectively. The natural frequency of the position sensing mode is lowered and tuned by the DC bias voltage applied to the position sense electrodes and then finely tuned by DC bias on a pair of force-balancing electrodes. To reduce the mass exciting along the sensing direction, we drive the mass by the same DC and opposite AC driving voltage on the oppositely placed comb-drives. It also features that the position sensing electric interference ins reduced. The mass is self-oscillated by the condition of limit cycle, so the mass is always oscillated in the natural frequency even if the natural frequency is varied by the environment and/or it has displacement-force nonlinear behavior. The gyroscope is fabricated on the silicon wafer by surface micromachining technology and the polysilicon is used as an active structure. The gyroscope has an active size of 700 by 600 micro meters, the thickness of the structure is 7 micron meters and the proof mass of 1 micro gram. To improve the resolution of the gyro, it is packaged in the 50 mili-torr vacuum package with a conditioning ASIC. Experimental results show that the gyroscope has the equivalent noise level of 0.1 deg/sec at 2 Hz, the bandwidth of 100 Hz, linearity of 1 percent FS and the sensing range of 90 deg/sec.

A comb driving vibratory micro-gyroscope, which utilizes the dynamically tunable resonant modes for a higher rate- sensitivity without an accelerational error, has been developed and analyzed. The surface micromachining technology is used to fabricate the gyroscope having a vibrating part of 400 X 600 micrometers with 6 mask process, and the poly-silicon structural layer is deposited by LPCVD at 625 degrees C. The gyroscope and the interface electronics housed in a hermetically sealed vacuum package for low vibrational damping condition. This gyroscope is designed to be driven in parallel to the substrate by electrostatic forces and subject to coriolis forces along vertically, with a folded beam structure. In this scheme, the resonant frequency of the driving mode is located below than that of the sensing mode, so it is possible to adjust the sensing mode with a negative stiffness effect by applying inter-plate voltage to tune the vibration modes for a higher rate-sensitivity. Unfortunately, this micromechanical vibratory gyroscope is also sensitive to vertical acceleration force, especially in the case of a low stiffness of the vibrating structure for detecting a very small coriolis force. In this study, we distinguished the rate output and the accelerational error by phase sensitivity synchronous demodulator and devised a feedback loop to maintain resonant frequency of the vertical sensing mode by varying the inter-plate tuning voltage according to the accelerational output. Therefore, this gyroscope has a high rate-sensitivity without an acceleration error, and also can be used for a resonant accelerometer. This gyroscope was tested on the rotational rate table at the separation of 50(Hz) resonant frequencies by dynamically tuning feedback loop. Also self-sustained oscillating loop is used to apply dc 2(V) + ac 30(mVpk) driving voltage to the drive electrodes. The characteristics of the gyroscope at 0.1 (deg/sec) resolution, 50 (Hz) bandwidth, and 1.3 (mV/deg/sec) sensitivity.

This paper presents a new accelerometer which detects applied acceleration by measuring the variation of the drain current of field effect transistors (FETs). This proposed accelerometer consists of a polysilicon plate, supporting beams and source/drains of n-channel metal insulator semiconductor FETs. The polysilicon plate used as the proof mass is suspended by four flexures and separated from the substrate. The comb finger structures at the polysilicon plate edge are used as gates of FETs. In the FET of the proposed accelerometer, gate oxide of a typical MOSFET is replaced with air gap between floating gate and substrate. As an acceleration perpendicular to the substrate is applied to the proposed accelerometer, the proof mass would have a displacement proportional tot he acceleration, and the gap between proof mass and substrate would vary. This will change the drain current of the FET because the drain current of a FET is inversely proportional to the gap between a gate and a substrate.

In this paper we describe a design methodology which has been successfully developed for the design of magnetic bearings. Its adaptation and application to the design of a micro magnetic bearing is presented. Particular design problems of micro magnetic bearing system are addressed, such as the selection of the bearing topologies, the magnetic modeling and design of the actuators, and the modeling and performance simulation of these bearing system. The design trade-offs are considered and it is shown that the design of actuators and their control systems need to be considered concurrently. As an example, design result for a micro magnetic bearing with a diameter of 2.1 mm are presented.

Molecularly-ordered thin-films comprised of nanosized inorganic particles and ionic polymer molecules have been fabricated on single crystal silicon, quartz and glass substrates by a novel molecular self-assembly process. X-ray photoelectron spectroscopy indicates that the formed cationic inorganic particles only adsorb on negatively charged and not on positively charged surfaces. Contact angle measurements demonstrate that the water contact angle oscillates regularly according to which ions form the outermost layer of the films. Thin-films ordered at the molecular level have been fabricated up to several hundred layers in thickness and characterized by UV-vis spectroscopy. Incorporation of different nanoparticles and polymer molecules allows tailoring of physical properties.

In this paper, the design and the fabrication of a two-axes polysilicon yaw rate sensor with four vibrating masses are presented. To confirm the first mode of the designed yaw rate sensor, ANSYS simulation was performed and the resonant frequency of 28.263kHz was obtained. Due to process variations, the fabricated structure may have different resonant frequencies for reference and detection vibrations. Therefore, a simple frequency tuning structure was utilized for frequency matching. To drive the designed structure at optimum condition, Q factor was chosen to be 1000 and the driving voltage was set to 26V for one set of masses and 35V for the other set of masses. With the selected driving condition, the reference vibration amplitude would result in about 10(Mu) m for all masses. Input angular rate of 90deg/sec would vibrate big masses and small masses with the amplitude of 0.17micrometers , respectively. In the fabrication of the designed yaw rate sensor, 6micrometers thick LPCVD polysilicon was used as structural layer over phosphosilica glass sacrificial layer. Polysilicon structural layer was doped with phosphorous diffused from PSG. The patterned structure was released by sublimation drying method using p- dichlorobenzene. The total area of the fabricated yaw rate sensor is about 1.9 X 1.4 mm².

The present paper reports the theoretical optimization and analysis of polarization maintaining fiber characteristics using design of experiments by Taguchi Method.

The authors report a large-flow microvalve which has an ability to replace conventional pneumatic control devices. The authors have analyzed the generating force for various driving methods and concluded a combination of silicon micromachined valve structure and electromagnetic driving is the best way for the large-flow control. The electro- magnetic actuator consists of an externally placed solenoid and a magnetic metal chip which is bonded to silicon valve chip. The actuator produces force larger than 0.1 N along 0.1 mm stroke. The valve structure is integrated on the silicon chip, which consists of an anisotropically etched orifice and a polysilicon valve sheet with springs. The polysilicon layer has a 30 micrometers thickness designed to obtain a strong structure enough to be operated with large force and large displacement. This microvalve can control large-flow gases with short response time and low power consumption, owing to electromagnetic driving. Moreover, the integration of the valve parts reduces its cost and assembly processes. The measured results show that 8.8 1/min air flow is controlled at 440 kPa by 210 mW electric power consumption and the response time is less than 3 ms, which are difficult to achieve by microvalves reported so far.

In this paper, a new method which simplifies the design process of micromachined deformable mirrors is presented. By varying the widths of an array of constant-pitched electrodes, the electrostatic-force profile needed to shape the mirror can be precisely controlled using only one voltage input. In the past, either several independent voltages were necessary or, if only one voltage was available, numerical schemes were required to search for the optimal sizes and locations of a few electrodes. A mirror is formed by a thin membrane micromachined from a silicon wafer and is coated with a thin metallic film. The electrodes are deposited on a ground plane over which the membrane is suspended. Viewing the mirror as a surface composed of many small patches with the same pitch, we can calculate the average force of each patch from the deformed shape using basic elasticity formulae. Using conformal mapping method, we can solve the analytical solution of the electrostatic field between the mirror and the electrode in one pitch. The relationship between the force and the width of the electrode is established. Finally, the widths of all the electrodes are obtained, and this new method applies equally well to the designs of both membrane electrostatic actuators and capacitive sensors.

The micro-EDM machining technique has been broadly applied to fabricate 2D and 3D micro-parts. It is difficult to produce a metal mold with dimension from several micrometers and with the accuracy in the level of micrometers . Poor accuracy comes from electrode wear during 3D micro-EDM machining. In this research, an efficient wear compensation cooperated with CAD/CAM path compensation is provided to improve the machining accuracy. In the experiments, by fabricating a micro-gear and sculpturing letters on surface of tiny steel ball, the technique provided in this research shows the expected results successfully.

A system for detection of volatile compounds has been developed based on the concept of an electronic nose. The detection mechanism relies on the change in electrical resistance that occurs when a conducting polymer sensing element is exposed to the gaseous sample. An array of such sensors in conjunction with pattern recognition data analysis are used to identify and quantify the compounds of interest.

To close the technological thickness gap between vary thin PZT-layer deposition and bulk PZT, a new technology called Jet Printing has been introduced recently, which can be used to deposit layers between 5 and 100 micrometers thickness. This technology is used for the first time to fabricate bimorph actuator elements suitable for actuation purposes in MEMS. At first, 10 to 40 micrometers thin PZT layers are deposited on beam shaped structures made of 30 micrometers thick steel. This basic actuator beams were stimulated by an AC voltage, and the reflected laser beam showed reasonable dynamic deflection angels of about 5 degrees maximum. Secondly, deposition on anisotropically etched silicon membranes with varying thickness from 25 to 125 micrometers was carried out. It appeared, that at a membrane thickness lower than 50 micrometers technologically effects can break the membrane. However, for membranes thicker than that, direct deposition after anisotropic etching could be applied successfully, and dynamic deflection of this membranes could be proofed by laser interferometric measurement. Finally, a small structure capable of diverting a laser beam and carrying out 2D scanning was designed and fabricated from 30 micrometers thick steel using laser ablation. The scanner is actuated by four actuator beams, on which 30 micrometers thick PZT has been Jet Printed as the actuating material. The electrodes on the beams can be stimulated separately, and therefore control the scanning direction. Experiments showed the capability of the structure to be actuated, and deflection angels up to 5 degrees could be measured.

This paper addresses the basic problems related to the design and development of a dual-block tactile sensor able to cover the same area of a single block sensor by adopting a plug-in arrangement. The improved performance obtained by adding a second block to the basic sensing unit are well suited for those devices where accuracy is fundamental for the system correct-working condition. The basic unit remains still adoptable for all those applications where less stringent conditions are required.

A surface micromachined accelerometer which senses an inertial motion with an area variation and a force balancing electrodes is developed. The grid-type planar mass of a 7 micrometers thick polysilicon is supported by four thin beams and suspended above a silicon substrate with a 1.5 micrometers air gap. The motion sensing electrodes are formed on the substrate. The sensor is designed as an interdigital rib structure that has a differential capacitor arrangement. The moveable electrodes are mounted on the mass and the pairs of the stationary electrodes are patterned on the substrate. In the accelerometer that has comb-type movable electrodes, the mechanical stress and the electrical pulling effects between a moveable electrodes and the fixed electrodes occur. However this grid-type structure can have a large area variation in a small area relatively without stress and pulling, high sensitivity can be achieved. In order to improve the dynamic rang and a linearity, a pair of comb shape force-balancing electrodes are implemented on both sides of the mass. The force-balancing electrodes are made of the same layer as the mass and anchored on a silicon substrate. When acceleration is applied in the lateral direction, the difference of capacitance results from the area variation between the two capacitors and is measured using a charge amplifier. As AC coupled complimentary pick- off signals are applied in paris of stationary electrodes, the undesirable effects due to temperature and electrical noise are reduced effectively. The accelerometer has a sensitivity of 28mV/g and a bandwidth of DC-120Hz. A resolution of 3mg and a non-linearity of 1.3 percent is achieved for a measurement range of +/- 9 g.

In this paper, simulation of dynamic characteristics of pneumatically driven micropumps is presented. SPICE was used as a system level simulator. The SPICE model employed equivalent electrical circuit parameters extracted by an energy based calculation method. The thickness, side length of the diaphragm and forward resistance of valves were selected as variable to study the effect of design parameters in the performance of micropumps. Since the flow and pressure response of micropumps are similar to those of a differential electrical circuit, two parameters, namely, maximum amplitude and time constant of the system were used to discuss the simulation results. The results are of fundamental important to the understanding and optimization of the micropump.

Miniaturized sensor for thermal analysis is fabricated using micromachining technique and its fundament al characteristics are obtained. This device fabricated in a Si substrate consists of monolithically integrated components of an air-bridge type microheater, a thin film thermocouple and a sample-holder. Boiling points of liquid samples, water and methanol, are observed in the heating curve and the heating-rate curve, and sudden decrease of the temperature at the dropping time of the liquid samples at room temperature due to the effect of evaporation heat is also observed. Loss of the sample due to the evaporation during heating was theoretically discussed.

In this paper we investigate an eddy current microsensor which uses a trans-impedance to minimize the influence of stray capacitances on its operation when being used for micromachine applications. The effect of stray capacitances can be minimized when using this type of amplifier by ensuring its input impedance is small. A technique for realizing very low input impedance over a wide bandwidth in these amplifier is studied. In additional new improved circuit configuration which further reduces the amplifier input impedance over a wider range of frequencies is investigated by computer simulation. Finally the experimental investigation of target materials suitable for achieving high sensor sensitivity is discussed.

We have investigated in detail the ultrasonic motors using two degeneration modes driven by the same-phase input signal, namely, one channel, and some constructions and characteristics of the prototype motors using disk vibrator based on this principle have been reported. However, operational characteristics of the motor were influenced considerably in proportion to the pressing force between the stator and the rotor. In this paper, some considerations on the effect are investigated experimentally. From measurements of the vibration mode in the operational state, it was found that the change of rotational direction of the motor is caused by the shift of the vibration axis of the mode synthesized from two degeneration modes. Revolution characteristics for both rotational directions of the improved motor are shown. The maximum torque and efficiency were about 4.5kgf-cm and 30 percent, respectively.

As a novel application of Silicon-based integrated optics, first result of a compact Mach-Zehnder interferometer are presented. This passive device is transformed into an active one by the deposition of a ZnO thin film transducer on the reference arm where the acousto-optics mechanism generates a sinusoidal phase modulation.

The surface micromachining process realized the dual-axis microgyroscope. The 7.5 micrometers -thick polysilicon layer deposited by LPCVD is used for the vibrating structure. In this research, we present a new structure with high angular inertia momentum and compact size. In particular, this structure can utilize a simple force-balancing torsional torque which does not need another top electrode layer to reduce the intrinsic non-linearity of a capacitive-type sensor. The gyroscope is tested in a high vacuum chamber for a high Q-factor. The sensing mode is separated 2 percent from the driving mode by applying the inter-plate DC tuning bias. The experiment resulted in a nose equivalent signal of 0.1 deg/sec.

We have developed the high sensitivity fiber optic Fabry- Perot pressure sensor with a Si₃N₄/SiO₂/Si₃N₄(N/O/N) diaphragm fabricated using micromachining technology in the anisotropic etchant KOH solution. The configuration of this sensor was a 2 cm length fiber optic Fabry-Perot interferometer bonded to a 0.6 micrometers thick diaphragm. When the area of the N/O/N diaphragm used in the experiments was 2 X 2 mm², the pressure sensitivity was 0.11 radian/kPa, and when the area was 8 X 8 mm², the pressure sensitivity was increased to 1.57 radian/kPa. The phase change was dependent upon the applied pressure linearly.

This paper investigates new design rules that will allow the development of high torque electrostatic micromotor through the cooperation of arrayed direct drive actuators. Electrostatic scratch drive actuators, which combine active frictional contact mechanisms with the electrostatic actuation are particularly analyzed because previous achievement shave pointed their ability to develop, at a low speed, high driving forces comparatively to their little size. Scratch drive actuators (SDA) have been already successfully applied, as an example for self assembling microstructures and micro optical bench actuation. Such interesting results which have been performed by using an individual or a few numbers of SDA, led us to make further investigations in order to optimize this new promising actuator technology. Consequently, we have mainly focused on new mechanisms which integrate combinations of a large number of SDA, in such a way to allow powerful annular and tubular micromotors to be designed, machined, and then characterized. This paper points our the main physical and technological principles that will allow high torque electrostatic micromotors to be realized in a near future. It also gives the first results that have been obtained on the design and surface-micromachining of annular and tubular micromotors. The previous result related to the batch fabrication of large and thin polysilicon sheets, which integrate up to several thousands of microactuators are also given. New concepts which will allow large size and high torque 3D electrostatic micromotors to be realized through the forming of thin polysilicon sheets, are finally described. The expected driving characteristics show the interest of both cooperative arrayed microactuators and direct drive frictional mechanisms.

A new micropump principle without mechanical valves is proposed. Flow rectification is achieved by a pair of dynamic valves, the pressure drop through each of which can be individually adjusted by controlling the liquid temperature in the valve channel, thus changing its viscosity. This method has a potential for miniaturization of complex liquid handling systems, since it allows bi- directional liquid transfer with a single micropump, by applying appropriate activation sequences for the valves and the pressure source. The necessary specification and the possible performance are predicted through FEM analysis of thermal and flow systems. By a preliminary experiment using a prototype pump structure fabricated with silicon based technology, the basic function of the valve elements has been confirmed.

Deposition of PZT with UV laser ablation for realization of thin film sensors and actuators. Deposition rate of more than 3 micron/hour was attained by pulsed KrF excimer laser deposition, which is fairly better than those obtained by other methods like sputtering and sol-gel process. Perovskite phase was obtained at room temperature deposition with fast atom beam (FAB) treatment and annealing. Cohesion between substrate and PZT were also improved with FAB irradiation during deposition. Smart MEMS is now a subject of interest in the field of micro optical device, micro pump, AFM cantilever devices etc. It can be fabricated by deposition of PZT thin films and micromachining. The reported thin films have been mostly prepared by sol-gel process and sputtering process. However PZT film of more than 1 micron thickness is difficult to obtain because of low deposition rate for sputtering process. However PZT film of more than 1 micron thickness is difficult to obtain because of low deposition rate for sputtering and accumulated thermal stress in sol-gel process. This is the reason why we applied excimer laser ablation for thin film deposition. Deposition was done in an ultra high vacuum chamber with 6 targets and a 3 inches wafer size substrate which can be heated up to 1273 K. Targets and substrate were rotated during deposition for improvement of thickness uniformity of deposited layer. Effects of deposition parameters such as LASER wave length, power density and radiation conditions were investigated on deposition rate and film properties. Effect of annealing was also investigated with XRD analysis. Relative dielectric constant is measured for thin films, and the micromachined cantilever beams were fabricated for measuring the deflection of the beams.

Although piezoelectric thin films are of great interest for actuator application in MEMS, deposition of PZT films with thicknesses between 5 and 100 micrometers has been hardly possible. It is therefore the goal of this paper, to investigate the properties of PZT-films of this thickness deposited by the recently introduced Jet-Printing System, especially concerning an application in micro actuator devices. First, PZT layers of thicknesses between 5 and 80 micrometers have been Jet-Printed on different substrates to investigate the compatibility of the deposition method with standard materials used for MEMS. The relative dielectric constant of the layers could be determined between 20 and 550, depending on annealing and deposition conditions. Following, on thin beam-shaped steel substrates PZT layers of 10 to 40 micrometers thickness were deposited. SInce the samples showed deformation caused by technology-introduced stress, the stress value is calculated by means of FEM calculation, and methods for avoiding and compensation of the deformation are introduced. Using the beam-shaped samples, for the first time the piezoelectric constant of the Jet-Printed PZT-layer was calculated to 20...30 10^-12 C/N from laser measurements of static and quasi-static beam deflection, and therefore piezoelectric actuation capability could be proofed directly.

This paper introduces a new principle of no-scanning tactile resonant sensor array. All sensory elements in this sensor array form independent oscillators which ave different resonant frequency because of the fabrication of different thickness on electrodes and the special resonant circuits connected with them. Once a pressure or force is applied on the surface of piezoelectric plane, the resonant frequencies in the application area will change along with diversity of the applied pressure or force quickly. The resonant frequencies in the application area will change along with diversity of the applied pressure or force quickly. The resonant frequencies in the application area will change along with diversity of the applied pressure or force quickly. The resonant signals in all sensor elements are taken out from parallel output lines continuously. Since only the data which have designated meaning are processed, thus the data are compressed and a real-time sensing system may be obtained. The output of the array is quasidigital signal and can be processed in a digital way easily, its antijam is well. The sensor array contains two functional units: the sensory unit, the signal generating and processing unit, which can be integrated or be wired together easily. So the sensor array may be feasible for both large dimensions sensing and perception of fine object.

Thermal expansion coefficient of heavily doped LPCVD polycrystalline thin film was extracted by microgauge sensors. When electrical power was applied to the microgauge, it was heated up and thermal expansion occurred. From the relation between applied current and measured displacement at the microgauge, thermal expansion coefficient of thin film was extracted. The results revealed a value of 2.9 X 10^-6 /K of thermal expansion coefficient of highly doped poly-Si thin films with standard deviation of 0.24 X 10^-6 /K.

The fundamental goal in FED technology is the ability to construct emitters that present high-electron-emission characteristics and reliability with a low turn-on voltage. Several types of micromachined field emitter arrays combining silicon/metal tips with diamond-like carbon (DLC) coating are fabricated and examined for their applications to FEDs. Although there are some fluctuations of initial conduction current due to the unstable electron emission from the sharp emitter tips, FEAs panel whose silicon/metal tips are coated with DLC film by PECVD and layer-by-layer deposition shows remarkably lowered threshold voltage with increased current density.

The possibility of practical thin-film electroluminescent (TFEL) displays using oxide phosphor emitting layers has been investigated with a single-insulating-layer device structure using a thick insulating ceramic sheet. Highluminance TFEL devices using rare earth- or transition metal-activated oxide phosphors consisting of binary, ternary and multicomponent oxide compounds are demonstrated. It is concluded that oxide phosphors are very promising as emitting layer materials for TFEL devices, because they can exhibit EL characteristics comparable with those of sulfide phosphors. It was found that various oxide phosphor TFEL devices can emit the three primary colors without the use of color filters. The emissions from the following highluminance oxide phosphor devices were found to be suitable for full-color displays: Ga2O:Mn, ZnGa2O4:Mn and Zn2SiO4:Mn for the green color and ZnGa2O4:Cr for the red color. In addition, a luminance of 592 cd/rn2 for yellow emission was obtained in a CaGa2O4:Mn TFEL device driven at 60 Hz. Keywords: Oxide Phosphor, Thin-Film Electroluminescent Device, Electroluminescence, Thin Film, Phosphor, Display, Flat Panel-Display, Oxide

This paper discusses the development of a high resolution digital readout from a 2D array of uncooled IR detectors. The need for a high resolution analogue to digital converter (ADC) is described and anew concept is presented. Experimental VLSI arrays have been designed using 0.8 micrometers CMOS technology and the pixel size is 40 micrometers X 40 micrometers . The concept has been demonstrated by using 320 parallel 16 bit ADCs in a 320 X 240 readout array with a frame rate of 30 Hz. High linearity and low noise is obtained and the power consumption for each ADC is 0.5 mW. The high digital resolution allows for digital offset correction off the local plane. A 16 X 16 version of the readout circuit has been postprocessed with uncooled IR detectors. These are currently under evaluation.

Two ITO-coated glass wafers are successfully bonded by the typical Si-Pyrex electrostatic bonding mechanism. Both Si- 7740 and Ti-(Li-doped SiO$02)) interlayer systems can be employed for the electrostatic bonding of 7059-7059 and 0080-0080 glass wafer pairs. This glass-to-glass electrostatic bonding process can be applied to the clean and tubeless packaging of field emission display panels.

This paper reports on the development of silicon microbolometer uncooled IR focal plane detector arrays at the Defence Science and Technology Organization (DSTO), in collaboration with the National Defence Research Establishment (FOA). The detector arrays were designed by Electro-optic Sensor Design, which also provided specialist scientific advice on array fabrication. Detector arrays are prepared by monolithic processing at DSTO, using surface micromachining to achieve thermal isolation, and are integrated on-chip with a CMOS signal conditioning and readout microcircuit designed by FOA. The CMOS circuit incorporates 16-bit analog-to-digital conversion, and is described in more detail in an accompanying paper presented. The ultimate objective is to develop 'smart' focal plane arrays which have on-chip signal processing functions, giving a capability for decision making such as automatic target detection. The silicon microbolometer technology described in the paper was invented at DSTO, and is representative of core technology employed in many initiatives world-wide. A brief overview will be given of theoretical considerations which influence detector array design, followed by an outline of recent developments in array processing.

In this work, a new type of membrane based sensor has been developed. Use of an insulating microfiltration membrane coated with platinum on both sides allows independent optimization of the reaction and signal generation components required for electrochemical sensing. The feasibility of signal generation and selectivity have been demonstrated for a simple electrochemical system as well as the glucose oxidase system.

In the aircraft industry the use of externally bonded composite repairs has become an accepted way of repairing fatigue, or corrosion, damaged metallic structural components. Optical fibers offer a means of monitoring the load transfer process in these repairs, and can therefore be used to provide an indication of the integrity of the repair. This paper describes the use of an array of fiber Bragg grating strain sensors (FBGs) for the in-situ monitoring of bonded repairs to aircraft structures and, in particular, the monitoring of crack propagation beneath a repair. In this work the FBGs have been multiplexed using a combination of wavelength and spatial techniques employing a tunable Fabry-Perot filer to track individual gratings. The multiplexed FBGs were then surface mounted on a Boron-Epoxy unidirectional composite patch bonded to an aluminium component. The sensors were located so as to monitor the changing stress field associated with the propagation of a crack beneath the patch. The ability of relating experimental results to sensor readings is then confirmed using both a thermo-elastic scan of the patch and 3D finite element analysis. Additionally, the relative merits of surface bonding verses embedding sensors are discussed, and a standardized embedding procedure for fiber optic sensor in Boron-Epoxy patches is described.

The quartz optical fiber bundle sensor for the image processing and temperature measurement is consisted by a number of optical subfiber bundles, each optical subfiber bundle is consisted by tow optical fibers. One optical fiber in all subfiber bundles are then bundled up for the image transportation and another optical fibers in all subfiber bundles are then bundled up for the image processing and the temperature measurement, and the temperature field of the whole image can be obtained by the image processing. The direct coupling theory between the optical fiber bundle and the measured target is studied in this paper. Our theory and experiment research proved that the target power transported by the optical fiber bundle does not depend on the coupling distance between the target and the optical fiber bundle, and does not depend on the coupling angle between the target surface normal and the axis of the end surface of optical fiber bundle when this angle is changed between +/- 15 degrees. Hence this instrument utilization and calibration is very easy and convenient. The temperature measurement from 120 degrees C-450 degrees C is realized by this instrument, the image resolution is better than 20pl/mm, the temperature solution is smaller than 0.2 degrees C. This instrument is a very good monitor for the medical surgical operation.

Smart Materials functions often mimic biological functions. Recent basic research at the US Army Research Office has focused on biomimetrics and meso-scale smart materials. Current ARO materials research interests and progress in these areas will be reviewed for sensors, molecular recognition, signal transduction, structures and control functions.

COnducting polymers such as polypyrrole and polyaniline are being extensively studied for their use in a wide range of new products. These materials are unique in that they have switchable properties due to their 2 or more mechanically stable oxidation states. Thus, films or coatings can be easily switched by the application of small voltages and currents to change the mechanical and electrical properties, the density, light absorbance and even to emit light in a diode arrangement. This paper discuss the factors that influence the performance of conducting polymers in four applications being developed at the Intelligent Polymer Research Institute: actuators, membranes, sensors and corrosion resistant coatings.

Optical fiber-based sensor instrumentation has been used extensively for the measurement of physical observables including strain, temperature and chemical changes in smart materials and smart structures, and have been integrated with MEMS devices to provide multi-measurement capability along the length of a fiber link or network. This plenary paper briefly outlines recent developments in such optical fiber sensor instrumentation. Fiber optic sensors are small in size, immune to electromagnetic interference and can be easily integrated with existing optical fiber hardware nd components that have been developed primarily for use in the larger telecommunications market. Such sensors can be easily multiplexed, resulting in networks that can be used for the health monitoring of large structures, or the real-time monitoring of structural parameters required for structural analysis and control. This paper briefly describes and compares three current fiber sensor configurations that use Fabry-Perot interferometry and fiber Bragg gratings and long-period grating elements to monitor strain, temperature and other parameters. Extensive details concerning additional related work and field test results and applications are discussed in the references.

Since inception 16 years ago, the MOSIS Service at the Information Sciences Institute of the University of Southern California has processed over thirty thousand IC Designs. Three years ago, it added access to commercial MultiChip Module (MCM) fabrication through MIDAS. To the list of standard offerings, MOSIS now introduces back end processing of MOSIS custom VLSI circuits for both suspended structure and diaphragm style MEMS. MOSIS presents an array of high- end VLSI technologies from various domestic foundries' standard processes for prototype and small volume quantities. Thus designers can develop low-cost IC's, MCM's and MEMS with a one-stop-shopping commerce style service. MOSIS functions as a 'transparent' third party interface between design and fabrication. The service offers ease of use through supported standard cell libraries and design tools, and with Internet design submission.Sharing the costs of NRE, masks and fabrication provides a low cost environment for users. MOSIS handles the front-end foundry tasks of data preparation and mask fabricate with fixed domestic and international price lists. MOSIS utilizes volume production lines at AMI, HP, Orbit, Vitesse, and MicroModule Systems. This paper discusses what MOSIS offers to the VLSI deign community, various applications fabricated through the service, as well as a conceptual design that draws from the various technologies discussed.

As the communication era comes in reality, SOC in microelectronics is not only an emerging issue for multiple applications, but the combination of sensor and the SOC, iMEMS, out of high density and low power micromachining technologies in semiconductor work has attracted many researchers for several years. For practical purposes, circular-shape SOI micro-cavity technology facilitates multiple sensors on very small chip size possibility, makes device easier to package than conventional sensor like pressure sensor and also diaphragm can be any shape, defining the diaphragm photolithographically and also provides very high over-pressure capability. This paper demonstrates the cross-functional result for stress analyses, for finding permissible diaphragm dimension by output sensitivity, and piezoresistive sensor theory from two-type SOI structures. Those results are also compared with the ones of circular-shape bulk-Si based sensor. It is observed that the double SOI structure shows the most feasible deflection and small stress at various ambient pressure. The SOI microcavity formed the sensors is promising to integrate with calibration, gain stage and controller unit plus high current/high voltage CMOS drivers onto monolithic chip.

A new design for the comb finger structures used in micromechanical electrostatic comb-drive actuators is presented. The new angled comb finger design is simulated using finite element analysis techniques and the results compared with hose obtained from the simulation of a conventional rectangular shaped comb finger. Results obtained demonstrate the greater actuation force generation capabilities of the new angled comb finger design. Actuation forces of up to 4.5 times those generated by standard comb finger designs have been obtained. Finally, a design approach has been demonstrated, allowing the successful design of a device based on the use of the new angled comb finger. This technique ensures the stability of the device throughout its operable range of displacements for both micron and sub-micron comb finger gap widths.