A micromachined and hermetically packaged rf switch with excellent performances and high reliability will be presented. Test results, future challenges for commercialization and possible applications will be addressed.

Backbone optical systems with ever-increasing transport capacity and routing complexity are driving the need for large port count core switches that can intelligently scale to manage the amounting bandwidth mass. Optical switching fabrics and in particular those based on MEMS technology potentially offer a scalable solution for the cross-connect network element. However the road from this exciting research endeavor to creating a reliable and manufacturable product is filled with challenges. The design, integration, and assembly of optical switch fabrics with over 1000 working ports stress all aspects of product development from component fabrication to mechanical tolerances and thermal manageability. In this paper we describe the myriad of contending optical, mechanical, and electronic design tradeoffs that contribute to the development of a 3D-MEMS based optical cross-connect.

A low-voltage bulk micromachined microgyroscope is presented in this paper. An ASIC (Application Specific Integrated Circuit) is integrated on the same silicon die to minimize the parasitic effect ant to ensure the high sensitivity of the microgyroscope. In addition, a comparison between comb- actuation and parallel-plate actuation was made mathematically to describe the system dynamics clearly. Constraints on the sensitivity and actuation voltage are extremely crucial to modern low-rate high-resolution microgyroscopes used in aerospace applications.

For airflow control applications, it is necessary to design robust MEMS actuators which could be placed on the wings of aircrafts. In this paper, we concentrate on in-plane actuators that are supposed to be an efficient solution for airflow control, and we present a design which uses a MEMS actuator embedded in a polymer layer which enables its in-plane movement. The knowledge of polymers mechanical characteristics -- and especially their behavior versus frequency -- is necessary for the design of such an actuator. We have determined these characteristics experimentally in order to be able to describe properly the actuator. With these measured values, we have explored two possible designs which are found to produce displacements of a 10 - 20 microns for a 3 mm actuator's total dimensions. Their frequency response is mainly limited to 2 to approximately 5 kHz by the increase of the polymer's stiffness.

A micromechanical silicon device suitable for DC-DC voltage up-conversion is investigated theoretically. The behavior of the converter is simulated in the time domain using a circuit simulator. In simulations ignoring parasitic capacitances, DC voltage of level of 16 V is increased to 32 V using a micromechanical converter. The output power is 2 mW for a device with 1 mm² surface area.

MicroElectroMechanical (MEMs) components and their applications to different RF and millimeter wave tunable filters are presented in this paper. Original topologies, design flows and RF performances of elementary building components like inductors and tunable capacitors are first detailed. Quartz or silicon-based inductors with quality factor Q in the order of 55 2 GHz and broad range MEMs varactors with continuous tuning values have been developed. Then, those elements are used to obtain several RF lumped element filters, one tunable discretely between 2.5 GHz and 3.5 GHz and another one tunable continuously between 1.8 GHz and 1.9 GHz. Finally, a distributed millimeter wave filter is proposed, with tunable center frequency and tunable bandwidth.

This paper reports the design, fabrication and test of a monolithically-integrated 4 X 4 free-space optical crossconnect using microfabricated polysilicon 3D-mirror to enable light-path switching for optical communication applications. The switch consists of 16 pairs of three- dimensional movable mirrors and draw-bride plate actuators, and four input and output fiber-optic guiding rails. The draw- bridge plates actuated by the electrostatic force drive the 3D-mirrors up and down to cut off the light beam or to let the light beam pass through. The optical crossconnect is fabricated using three-layer-polysilicon surface micromachining technology. The size of the whole structures is 5 mm X 5 mm . The maximum driving voltage is about 45 V, and its resonant frequency is about 5 KHz (200 micrometer switch time). The optical insertion loss of about 1.5 dB and the crosstalk of less than -60 dB have been obtained while using GRIN-lens to collimate the input optical signals.

One of the most promising applications of MOEMS in Optical Networks is represented by free-space electro-mechanical Optical Cross-Connects (OXCs); these components show lower attenuation and lower insertion losses than concurrent components based on waveguides. Although some commercial micromachined electro-mechanical OXCs have been recently announced in the market, further deployment of these devices will certainly require decreasing insertion losses by proper design techniques of both, the electromechanical devices and the system packaging. In this document, we study insertion losses in micromachined free-space OXCs and the related packaging challenges; we assume in our discussions Single Mode Fiber (SMF) Cross-Connects using mirrors as beam steering devices. We start with an introduction to micromachined OXCs architectures, actuation mechanisms and collimators. In section 2, we present a study of insertion losses in SMFs links; the coupled effect of lateral and angular fiber misalignments is discussed. In section 3, we discuss insertion losses in OXCs when quarter-pitch GRIN lenses are used as fiber collimators; both sections 2 and 3 are based on Gaussian beam optics. In section 4, we explore the application of Scalar Diffraction Theory to OXC design, this is for calculating insertion losses including diffraction at the mirror plane. Finally, conclusions on insertion losses and the required fiber positioning accuracy are given.

Micromechanical oscillators in the radio frequency (rf) range were fabricated in the form of silicon discs supported by a SiO₂ pillar at the disc center. Effective spring constant of this oscillator can be controlled within the range (Delta) f/f approximately 10^-4 by a low power laser beam, (P_laser approximately 100 (mu) W), focused at the periphery of the disc. Parametric amplification of the disc's vibrations was achieved through a double frequency modulation of the laser power. An amplitude gain of up to 30 was demonstrated, with further increase limited by non-linear behavior and self-generation. Phase dependence, inherent in degenerate parametric amplification, was also observed. Self- modulation of the CW laser beam (P_laser approximately 100 (mu) W) provided by placing the disc oscillator into an interference pattern setup can lead to parametric self- excitation.

We report in this paper the study of a new metallic microresonator realized by UV-LIGA technique. This kind of device is excited electrostatically and takes advantage of the contour modes or Lame-modes of the structure. Design methods of such device are presented and simulated with a Finite Element Program. Details on the microfabrication process are also presented. The vibration modes are detected with an optical bench set-up and preliminary electrical results are presented. A comparison between experiments and numerical predictions are finally discussed.

The integration of photo-detectors onto a standard CMOS integrated circuit is presented. This device provides the optical front end for a real time centroid detection system to be used as part of a larger system for implementing a Shack- Hartmann wavefront sensor. A hardware emulation system containing a Field Programmable Gate Array is used to prototype suitable algorithms prior to IC fabrication. Data is presented on the performance of photodetectors and the ability to extract in real time a centroid coordinate.

A laboratory model of a gas sensor substrate produced in microelectronic technology has been experimentally analyzed and simulated by means of a 3D FEM model. This paper discusses its thermal and mechanical behavior under different working temperatures. The thermal expansion mismatch between different materials induces thermal stresses and structure deflection. Simulated and experimental results are proved to be in good agreement. Moreover, the proposed design offers low-power consumption, good thermal uniformity, low thermal inertia and mechanical stability up to 650 degrees Celsius.

This paper describes coupled-effect simulations of smart micro gas-sensors based on standard BiCMOS technology. The smart sensor features very low power consumption, high sensitivity and potential low fabrication cost achieved through full CMOS integration. For the first time the micro heaters are made of active CMOS elements (i.e. MOSFET transistors) and embedded in a thin SOI membrane consisting of Si and SiO₂ thin layers. Micro gas-sensors such as chemoresistive, microcalorimeteric and Pd/polymer gate FET sensors can be made using this technology. Full numerical analyses including 3D electro- thermo-mechanical simulations, in particular stress and deflection studies on the SOI membranes are presented. The transducer circuit design and the post-CMOS fabrication process, which includes single sided back-etching, are also reported.

This paper describes a CMOS-compatible self-testable uncooled InfraRed (IR) imager that can be used in multiple applications such as overheating detection, night vision, and earth tracking for satellite positioning. The imager consists of an array of thermal pixels that sense an infrared radiation. Each pixel is implemented as a front-side bulk micromachined membrane suspended by four arms, each arm containing a thermopile made of Poly/Al thermocouples. The imager has a pixel self-test function that can be activated off-line in the field for validation and maintenance purposes, with an on-chip test signal generation that requires only slight modifications in the pixel design. The self-test of a pixel takes about 15 ms. The area overhead required by the test electronics does not imply any reduction of the pixel fill factor, since the electronics fits in the pixel silicon boundary. However, the additional self-test circuitry contributes to a small increase in the thermal conductance of a pixel due to the wiring of a heating resistor over the suspended arms. The self-test capability of the imager allows for a production test with a standard test equipment, without the need of special infrared sources and the associated optical equipment. A prototype with 8 X 8 pixels is currently in fabrication for validation of the self-test approach. In this prototype, each pixel occupies an area of 200 X 200 micrometer², with a membrane size of 90 X 90 micrometer² (fill factor of 0.2). Simulation results indicate a pixel thermal conductance of 22.6 (mu) W/K, giving a responsivity of 138 V/W, with a thermocouple Seebeck coefficient that has been measured at 248 (mu) V/K for the 0.6 micrometer CMOS technology used. The noise equivalent power (considering only Johnson noise in the thermopile) is calculated as 0.18 nW.H^-1/2 with a detectivity of 5.03 X 10⁷ cm.Hz^1/2.W^-1, in line with current state-of-the-art. Since the imager may need to measure irradiation intensities below 1(mu) W, with a pixel output voltage much smaller than 1 mV, the analog front-end electronics incorporated on the chip uses modulation and correlated-double-sampling to reduce the amplifier offset and the noise floor.

This paper presents the simulating and experimental results of a micromolding process for fabrication of three-dimensional (3D) microcomponents. The maskless process utilizes a micro electrical discharging system for bulk machining, then finish machining using focused-ion beam to sputter the mold microcavity, which is then filled with various types of plastics. Simulation using commercially available software reveals possible problems in micromolding, and the simulation results of microgears ((phi) 100 - 1000 micrometer diameter, 1:1 aspect ratio) are compared with those from actually molded microgears. Although the software prohibits modeling of a stand-alone microgear with diameter below (phi) 1000 micrometer when using a 2.5 D model and (phi) 220 micrometer for a 3D model, the simulation succeeds upon integrating a microgear of (phi) 100 micrometer with a larger base. Selecting the polymers from the built-in data bank, the simulation pinpoints locations for trapped gas, predicts filling time, volumetric shrinkage, uniformity, and distribution of pressure, shear rate, stress... It correctly predicts underfilling of the cavity when the mold temperature is below a threshold, but fails to locate the weld lines. Minimum channel sizes for proper flow of several plastics are presented, and the mold temperature must be controlled for proper flow of polymer into a microcavity. The measured viscosity of tested polymers compliments the experimental and simulating results.

Deep Lithography with Protons (DLP) is a rapid prototyping technology for the fabrication of 3D micro-optical precision components. In this paper we will demonstrate how we made this DLP technology compatible with commercially available injection-molding and vacuum casting techniques, allowing to mass-replicate high-quality micro-optical modules at low cost. We will illustrate our technology by presenting optical characteristics of different refractive components made in optical-grade plastics such as polymethyl-methacrylate (PMMA), polycarbonate (PC) and semiconductor compatible plastics with high glass-transition temperatures such as COC.

The paper represents the design and fabrication of an electrostatic micro actuator with p+ Si cantilevers. The micro actuator consists of a plate suspended by four p+ silicon cantilevers and an electrode on a glass substrate. The p+ Si structure is fabricated by the boron diffusion process and the anisotropic wet etch process. The cantilevers of the micro actuator curl down because of the residual stress gradient in p+ silicon. When the electrostatic force is applied to the p+ cantilevers, the vertical displacement of the plate can be achieved. The deflection of the cantilever due to the residual stress gradient and the vertical displacement by electrostatic force were calculated. The displacement of the plate was measured with a laser displacement meter for various input voltages and frequencies. The feasibility of the proposed micro actuator for the application to optical pickup devices or optical communication devices was confirmed by the experiments.

The novelty of our study lies in the first controlled use of the phenomenon of stiction to lock three-dimensional self- assembled polysilicon microstructures. The stiction refers to the permanent adhesion of the microstructures to adjacent surfaces. It can occur either during the final stage of the micromachining process, that is to say the releasing of the microstructural material, or after the packaging of the device, due to overrange input signals or electromechanical instability. As a result, we often regard stiction as a major failure issue in the MEMS field of research. This paper reports both the theory of our stiction-controlled locking system operation mode and the validation of our original concept through the stiction-locking of a 3-D self-assembled device.

This paper presents the principle and fabrication of a novel micro mass spectrometer and emission test of hot electron for ionization. A micro mass spectrometer consists of a micro ion source and a micro ion separator. The micro ion source consists of a hot filament and grid electrodes. Electrons emitted by a hot filament are to ionize some sample molecules. The ions are accelerated to an ion detector by an electric field. Mass can be analyzed by using the time of fight depending on the mass charge ratio. The current of hot electron emission from the hot filament is measured for various input voltages.

We report on the design, the fabrication, the characterization and the demonstration of scalable multi-channel free-space interconnection components with the potential for Tb/s.cm² aggregate bit rate capacity over inter-chip interconnection distances. The demonstrator components are fabricated in a high quality optical plastic, PMMA, using an ion-based rapid prototyping technology that we call deep proton lithography. With the presently achieved Gigabit/s data rates for each of the individual 16 channels with a BER smaller than 10^-13 and with inter-channel cross-talk lower than -22dB the module aims at optically interconnecting 2-D opto-electronic VCSEL and receiver arrays, flip-chip mounted on CMOS circuitry. Furthermore, using ray-tracing software and radiometric simulation tools, we perform a sensitivity analysis for misalignment and fabrication errors on these plastic micro-optical modules and we study industrial fabrication and material issues related to the mass- replication of these components through injection-molding techniques. Finally we provide evidence that these components can be mass-fabricated in dedicated, highly-advanced optical plastics at low cost and with the required precision.

Micro-optical-electrical-mechanical systems (MOEMS) present a new set of challenges for systems on a chip (SoC) and mixed- technology designers including the need for mixed-signal multi-domain simulation. We present new modeling techniques for optical and mechanical MEM components and apply these models to the simulations of a MOEMS switch for optical fiber telecommunications applications.

A method for integrating optical wave propagation into electrical simulators is presented. For this purpose the Beam Propagation Method has been implemented using the HDL-A^TM language. This enables the simulation of optical wave propagation on the system level, using current Microsystems CAD tools. Some typical optical components have been simulated using this technique and satisfactory results were obtained. This enables the analysis of MOEMS components into standard Microsystems CAD tools using electrical simulators.

As MOEMS (Micro-Opto-Electro-Mechanical Systems) transition from laboratory curiosities to production products inserted into telecommunication systems, a top down design flow is necessary to minimize time-to-market. We present a structured- custom approach for MOEMS design based on the concept of using parameterized behavioral models as a means to improve and speed up the design process. This approach enables a user to quickly explore a larger design space on the interaction of the behavioral models with their surrounding system. Once the simulation is completed to the designer's satisfaction, a device layout can be output for FEM verification on critical areas or to generate the masks for fabrication.

We have recently developed in our laboratory a new integrated photodetector called BDJ. This detector allows determination of the wavelength of a monochromatic light. It was used to realize colorimetric applications. To develop such optoelectronic systems or microsystems we need simulations of their electronic behavior. Simulators like SPICE give in their libraries models for electrical components but not for optoelectronic components like photosensors or optic system. So we have developed a SPICE model to simulate the BDJ detector behavior and the optic source response. This model was implemented under SPICE and to illustrate its use, we have chosen to simulate two colorimetric applications developed in our laboratory; the first one allows determination of iron concentration and the second of the pH of solutions. In these applications, the optic system is composed of a light source (in practice Led's), and of a tube containing a liquid sensitive to the incident light wavelength; the transmission coefficient of the liquid depends on iron concentration in the first case and on reactive concentration and pH in the second case. Behavioral models of this optic system were included in the BDJ detector SPICE model. So we can obtain photocurrents ratio versus iron concentration or pH and reactive concentration. This system was simulated with an electronic associated circuit. This circuit is a classic analog circuit including several operational amplifiers. The optoelectronic system with associated circuit was described and simulated under SPICE and gives good results in comparison with measurements.

A methodology for predicting sites and modes of thermomechanical failure in IC and MEMS packages is developed. Singular stress fields around several stress concentration locations in a typical plastic-encapsulated IC package are calculated using special variable-order singular boundary elements and the singular value decomposition method. The strain energy density distributions around all the stress concentration locations are then obtained from the singular stress fields and compared. The most likely failure site as the temperature of the package is raised is then determined as well as the likely modes of failure, i.e. interfacial delamination or cracking of mold compound.

This paper demonstrates that RF MEMS micro-switches can be realized with a low cost MEMS technology such as MUMPs. Two different switches are proposed, namely the hinged beam switch and the gold overflowing switch. Their concepts, design and characterization are described in details. On-resistance as low as 5 - 6 (Omega) for the gold overflowing switch and 2 - 3 (Omega) for the hinged beam switch have been measured. Finally, experimental measurements showed that force and electrical current had strong influences on the overall electrical contact.

This work considers the reliability of an elementary 3D structure, and particularly the response of a homogeneous, clamped-clamped polysilicon microfabricated beam, buckling under the compressive force produced by Scratch-Drive Actuators (SDA). First, using Galerkin's method, the governing partial differential equation reduced to a modified Duffing equation and was solved by the harmonic balance method. Besides the solution of simple harmonic motion (SHM) and superharmonic motion (SPHM) were found numerically using a Newton iteration method. Then, the study of continuity -- of these solutions -- allowed to analyze the stability boundaries. Finally, Runge-Kutta numerical integration method was used to investigate the snap-through problem. Intermittent, as well as continuous, snap-through behavior was obtained. The theoretical results agreed well with the experiments.

A workstation for the testing and modification of IMEMS, incorporating a laser vibrometer, surface profiler and a laser for ablation, is described. Initial results have demonstrated the ability to do dynamic and static testing rapidly at the wafer level. Electrostatic actuation is shown to be one feasible method of driving the devices on a wafer; the other methods are being explored.

Component level (nodal) simulations have been proposed to both implement closed loop simulation of complete microsystems to support the migration to shorter design cycles and implement fault models of micro-mechanical components. Within such a simulation environment, library cells in the form of behavioral models, are used for the basic components of microelectromechanical (MEM) transducers, such as beams, plates, comb-drives and membranes. This paper presents both a methodology to generate the model parameters required for the implementation of accurate component level fault models and simulation results from a number of representative defective structures in a MEMS product.

Recently, optical MEMS devices have gained considerable attention in the telecommunications industry -- particularly in the optical networking and switching arenas. Since optical MEMS are micro-systems which rely on high precision optics, electronics and mechanics working in close concert, these emerging devices pose some unique packaging challenges yet to be addressed by the general packaging industry. Optical MEMS packages often are required to provide both optical and electrical access, hermeticity, mechanical strength, dimensional stability and long-term reliability. Hermetic optical access necessitates the use of metallized and anti- reflection coated windows, and ever-increasing electrical I/O count has prompted the use of higher density substrate/package technologies. Taking these requirements into consideration, we explore three ceramic packaging technologies, namely High Temperature Co-fired Ceramic (HTCC), Low Temperature Co-fired Ceramic (LTCC) and thin-film ceramic technologies. In this paper, we describe some optical MEMS packages designed using these three technologies and discuss their substrate designs, package materials, ease of integration and assembly.

Co-simulation of MEMS and their packages is indispensable if the thermal behavior of the MEMS device is critical. For the co-simulation we need a reduced order thermal model of the package in the form of either behavioral or network model form. The paper presents a method for the automated generation of dynamic thermal multi-port models of packages, based on simulation results. The method is general, in will be applicable also for the direct generation of package multi- port network models of thermal transient testers.

An experimental investigation was performed to study the heat transfer of flat micro heat pipe (FMHP) arrays with 38 triangular microgrooves. A heat pipe is an effective heat transport device that uses the latent heat of vaporization and operates without external power and achieves very high thermal conductance by means of two-phase fluid flow with capillary circulation. The overall size of the FMHP is 24 mm X 16 mm X 1.25 mm. The FMHP that can be put underneath microelectronic die and integrated into the electronic package of microelectronic device has been fabricated and characterized. Water was used as a working liquid. The fabrication and heat transfer details along with steady state horizontal orientation performance test results are presented. The experimental results show the temperature decrease of 12.1 degrees Celsius at the evaporator section for the input power of 5.9 W and the improvement of 28% in effective thermal conductivity.

Micro-optoelectromechanical systems (MOEMS) having valuable performance, size, and cost attributes offer novel solutions to the design of lightwave network elements. We will discuss the new challenges that realizing these benefits presents to the field of photonic packaging.

MicroElectroMechanical Systems made from single crystal silicon, and operated in torsion are used to rotate micro- mirrors for adaptive optics and for optical switching, to measure atomic forces, and to characterize the silicon at the micro/nm-scale. The design and characterization of torsion actuators for a mirror array and a scanning probe z-motion actuator will be discussed.

With the rapid development of MicroElectroMechanical Systems (MEMS) technology, there is a demand for layout synthesis tools which can directly translate high-level design specifications into valid MEMS device layout. These synthesis tools can help designers to rapidly explore the entire design space given user-specified constraints, and assist in building complex arrayed MEMS devices by quick design of individual cells. Usually in MEMS design, designers need to decide on a certain topology, make trade-offs between performance specifications and assign values to a set of variables which can represent a valid design. Physical layout is then generated from the set of variables. Usually, the large number of variables and the nonlinearity of the equations which link these variables makes the optimum trade-off between specifications very difficult to find by hand calculations. In this paper, we extend the synthesis techniques to be able to generate automatically an optimized MEMS component from its behavioral description. The resulting MEMS structure should match in performance, compatibility, and right interfacing with the electronic circuitry and/or other MEMS devices connected around. A thermopile design fabricated with AMS 0.6 micrometer bulk micromachining technology is being used to demonstrate the ability of such synthesis approach.

MEMS design environments are often FEM analysis centric. This relationship has kept MEMS design in a relative niche situation understood by experts. MEMSMaster implements a new design methodology for MEMS prototyping, based on a predefined set of parameterized elements composing dedicated libraries. It should ease access to MEMS technology to a wider audience.

A fundamental approach to a coherent design strategy for microsystems is presented in this paper. Establishing such a concept can provide undeniable advantages concerning manpower, technical resources and development time. Prevalent design steps are discussed in detail, referring to the suggested ideas. Several microsystem applications and software tools are taken into account to illustrate the main aspects of a consistent design flow. The approach of behavioral physical modeling in combination with model based design optimization applying efficient and robust numeric methods in both fields allows pre-production optimization. Thus, overall development and redevelopment effort can be reduced significantly.

High frequency, micromechanical bandpass filter, with tunable frequency and bandwidth are demonstrated in a polysilicon surface micromachining technology. These filter utilized a parallel-resonator architecture, in which properly phased outputs from two or more micromechanical resonators are combined to yield a desired filter spectrum. Damping effect was shown to have a significance factor in affecting the flat passband of the filter and will be further analyzed in this paper.

Micromachined planar spiral inductors and transformers have been largely proposed for RF applications, using MEMS processes. Q-factors and self-resonant frequencies have been significantly increased by suspending such structures. However, thermal and mechanical properties are somewhat compromised. In this paper, a complete analysis of such parameters is presented through extensive finite element method (FEM) simulations. Partially released structure is proposed to avoid these troubles.

Improvement of therapies and diagnosis methods require the acquisition of clinical data with optimal accuracy and reliability. Combination of recent progresses in SOI micromachining and telemetry lead to the development of a new miniature pressure sensor acquisition microsystem to be inserted as close as possible to the organ or the targeted area. Moreover a wireless RF powering and data transmission has been optimized in order to allow a non-invasive acquisition chain.

This paper presents an implantable telemetry LC resonance-type pressure sensor to measure the cerebral ventricle pressure. The sensor consists of an inductor and a capacitor. The LC resonant circuit consists of the sensor and an external antenna coil that are coupled magnetically. The resonance frequency of the circuit decreases as the applied pressure increases the capacitance of the sensor. The sensor is designed in consideration of the biocompatibility and long lifetime for continuous monitoring of the ventricle pressure. This study is focused on the miniaturization of the sensor with a low resonance frequency and a high resolution. The sensor is simple to fabricate and small in comparison with others reported previously. The inductor is fabricated by electroplating and the variable capacitor is constructed with a flexible p+ diaphragm. Also, the deflection of the diaphragm, the variation of the capacitance and the resonance frequency are analyzed and calculated for the ventricle pressure ranging from 0 to 7 kPa.

We review the use of statistical design and analysis of computer experiments (DACE) for the generation of parsimonious, surrogate models, also known as metamodels. Such metamodels are used to replace cpu- or memory-intensive, discretized approximations that often arise in MEMS and MOEMS. Emphasis is placed on optimal designs.

A design method for high-order electro-mechanical filters that makes use of the equivalence between lumped-parameters electrical and mechanical systems is presented. Conditions for existence of the equivalent mechanical system are derived, and electro-statical coupling of micro-mechanical resonators is introduced. The application to the simulation and design of a bandpass filter with finite transmission zeros implemented in a thick-layer epi-poly silicon micro-machining technology is shown.

In this work, a behavioral Modeling of RF VCO circuit which has a tank designed by Microelectromechanical system (MEMS) technology is presented emphasizing robust design that can obtain the parametric variable of the suspended spiral inductor and the MEMS tunable capacitor to high performance and reliable design of the VCO circuit. The MEMS spiral inductor has a low phase noise effect on the VCO output, and the MEMS tunable capacitance has very high quality factor with enabling 20% change of oscillation frequency. The designed monolithic RF VCO circuit and the high-Q MEMS inductor and tunable capacitor are modeled using specter-s simulator in the CADENCE design framework and (Verilog-A) behavioral simulator. Complete monolithic fabrication of RF VCO with high-Q MEMS devices using standard CMOS process (MOSIS, AMI 1.2 micrometer).

This paper describes a new approach for 3D full-wave electromagnetic analysis using integral equation formulation. The resulting system of equations is suitable for use with Arnoldy based model order reduction. This paper will demonstrate that this approach for modeling of electromagnetic actuated devices is more accurate and about 1000 times faster than traditional methods.

The aim of this work is that of analyzing how the discretization of a coupled electro-mechanical system has to be approached to have accurate results from a Finite Element Method (FEM) simulation. Main aspect concerns the definition of the finite element mesh at the interface between the two domains. From this point of view a hybrid approach is proposed, where a fixed mesh is used for the mechanical structure and for the electrostatic area, whereas a morphing approach is followed for the volume that surrounds the most deformable part of the structure. Other aspects related to the electrical domain discretization, as open boundary modelling, pole positioning of infinite mapped element dimension of the electrostatic area were also considered. Numerical tests were carried out in the simple case of a cantilever, following an explicit coupled solution based on an iterative scheme elaborated in ANSYS^TM parametric design language (APDL).

The use of micro-fluidics in MEMS device design and implementation is becoming a common practice, especially in the area of biomedical devices. As with all MEMS devices, a validated analysis tool can be invaluable in the design and development process. One of the more common manifestations of micro-fluidics in MEMS design is in the area of squeezed film damping. When one surface moves in close proximity to another solid surface, the fluid in the space between the moving surface and the solid surface can have a significant effect on the dynamics of the moving plate. If the fluid flow in the gap can be assumed to be quasi-steady and viscous-dominant, and if the gap height is small compared to the plate width, the velocity profile of the fluid between the moving plate and the solid surface can be approximated as parabolic in the thickness direction. In this case, the Navier-Stokes equations governing the fluid flow can be reduced to a scalar equation in terms of the fluid pressure. This squeezed film model can be combined with a solid mechanical (finite-element) model in order to perform dynamic fluid-structure interaction analyses for cases in which the above assumptions are valid. In such an analysis, the 3-dimensional solid mechanical model will provide the plate geometry, location, and velocity to the squeezed film model, which will in turn provide the resulting fluid pressure on the moving plate to the solid mechanical model. In this paper, cases will be presented in which the stated assumptions will be validated, and the relevant equations will be derived for both compressible and incompressible fluids. Examples of solid and perforated plates moving in compressible and incompressible fluids will be provided, and their results will be verified against fluid dynamics theory.

The stability of micromechanical capacitive transducers depends on the stability of mechanical and electrical properties. Charges trapped on the native oxide layers of the micromechanical electrodes, can create significant electrostatic forces in the absence of an external biasing voltage. The amount of trapped charges fluctuate in time due to various tunneling processes and deteriorate long-term stability of capacitive MEMS sensors. We have investigated the electromechanical stability of commercial angular velocity sensors and low-g accelerometers and found drift rates on the order of 0.01 %/h even after several hours after a step in the bias voltage. After correcting for the drift due to charge tunneling using an empirical fitting functions we find mechanical stabilities in the level of ppm/h.

A huge market development is expected for modern drug discovery and genomic analysis when rapid parallel analysis of a large number of samples gets available at affordable costs. The state of the art shows that low cost devices can be fabricated in mass production by micromolding of polymers. In close collaboration, Greiner Bio-One and Forschungszentrum Karlsruhe have developed a single-use plastic microfluidic capillary electrophoresis (CE) array in the standardized microplate footprint. This paper presents the results of experiences which show that hot embossing with a mechanically micromachined molding tool is the appropriate technology for low cost mass fabrication. A subsequent sealing of the microchannels allows sub-microliter sample volumes in 96- channel multiplexed microstructures.

The fabrication and the design of a new fiber connector for up to 16 single- or multimode fibers is presented. The connector features the following essential advantages: low cost fabrication by micro injection molding, easy assembly due to elastic alignment structures made possible using LIGA technology and bonding by UV-curing adhesive, and a hermaphroditic connector design in order to avoid damage of the precision part of the ferrule. The mean insertion loss is 0.35 dB with multimode fibers and as it turned out from first experiments 1.16 dB with singlemode fibers.

Due to the ongoing growth of microsystems' complexity, there is an urgent need for automatic optimization. In order to include it seamlessly in the customary design process, the algorithms have to be fast and robust. Calculations of the quality function call for at least one FEM-, netlist based or behavioral simulation. Thus the optimization process is a very time consuming task. This paper presents a methodology for enhancing the convergence characteristics of heuristic search methodologies.

Modern microsystem technology generates a great variety of very small sensors and actuators. With the use of capacitive measurement or moving principles these components have a very low power consumption and with some data preprocessing they can be used in passive telemetry systems, which need no integrated battery. Instead, they use two loosely coupled coils to realize the energy transfer. To create very small systems, e.g. for the implantation inside the human body, the use of an application specific integrated circuit for the telemetry will be necessary. In this paper a design strategy for the realization of implantable telemetric microsystems and a building set with different blocks for the creation of an application specific telemetry chip is presented. In addition to the necessary main building blocks like rectifiers, voltage regualtors and blocks for the uni- or bi-directional data transmission the set also includes some supplementary blocks like an auaotmatic resonance adjust. All blocks are realized in a standard CMOS process (a 0.7 um CMOS process with some analogue add-ons) and therfore very small and cheap systems can be created.

An electrostatically actuated microrelay with large displacement, small actuation voltage and limited plate surface dimensions is designed to meet stringent telecommunication switching requirements. Fabrication feasibility and performance characteristics of the device are evaluated using a commercial CAD for MEMS tool. Simulation results of the device performance including pull-in voltages for different suspension stiffness variations, natural frequencies, stresses and restoring forces are presented.

An eigenvalue analysis of a tunable micro-mechanical actuator is presented. The actuator is modeled as a continuum structure. The eigenvalue modified by the tuning voltage is computed through the linearization of the relation between the electrostatic force and the displacement at the equilibrium. A staggered algorithm is employed to perform the coupled analysis of the electrostatic and elastic fields. The stiffness matrix of the actuator is modified at this equilibrium state. The displacement field is perturbed using an eigenmode profile of the actuator. The configuration change of the actuator due to perturbation modifies the electrostatic field and thus the electrostatic force. The equivalent stiffness matrix corresponding to the perturbation and the change in the electrostatic force is then added to stiffness matrix in order to explain natural frequency shifting. The numerical examples are presented and compared with the experiments in the literatures.

Manufacturing test structures of microsensors and microactuators is very expensive in terms of time and materials. In a conventional design process, this limits the number of design variants to be considered. For this reason, computer-supported design techniques are becoming more and more important in microsystems technologies. In this paper, a system model of an IR gas sensor is presented. This model allows designs to be optimized, e.g. for use of the analysis chamber also to detect other gases with different absorption characteristics.

Modelling of a silicon resonator as a pressure sensor is presented. The resonator is electrothermally excited and the resonance frequency shift is detected by a piezoresistive thin film detector. Computer simulation using commercial MEMS software tool IntelliSuite^TM is compared with analytical model. Various design aspects, such as the pressure sensitivity, electrothermal heating of vibrating beam, influence of detection current and damping effect are investigated. Silicon resonator sensor have been fabricated and measured. The characteristics predicted by computer simulation has been confirmed by experimental results.

A varactor with a wide tuning range is essential to adjust the desired frequency band among a wide Gigahertz range and compensate for process deviation as well as effects of temperature. Nowadays, conventional varactors with high quality cannot be available in standard silicon processes; furthermore, they cannot avoid high losses at high frequencies due to the nature of semiconductors. A novel micromachined varactor with a wide tuning range is presented. It can provide a digital selection of capacitance. The electroplating process was singled out to fabricate such as device, with its feature of high aspect ratio. The design has been verified through a finite-element analysis to show a tuning range of 350%.

Ferroelectric films of lead zirconate titanate (PZT) are currently attracting attention because of the large number of potential application in micro actuators, such as micro- mirror, micro-pump and multi-probe cantilever of AFM. In this study, thin films of Pb (Zr_0.52Ti_0.48) O₃ (PZT) 1.8 to approximately 2.0 micrometer thick on a Pt/Ti/SiO₂/Si substrate were prepared by excimer laser ablation and were crystallized by subsequent annealing. Crystalline phases in the PZT films were investigated by X-ray diffraction analysis (XRD). The microstructure and composition of the films were studied by scanning electron microscopy (SEM) and electron probe microanalysis (EPMA), respectively. The effect of the Pb content of the target on electrical properties of PZT thin films was investigated. The PZT films with a well- crystallized perovskite phase were obtained by adding 20 wt % excess PbO to the target and annealing at 750 degrees Celsius for 90 min. The remanent polarization and the coercive field of this 0.8 micrometer think film were 23.6 (mu) C/cm² and 60.0 kV/cm, while the dielectric constant and loss values measured at 1 kHz were approximately 935 and 0.04, respectively. Our results demonstrate that a few micrometers thick PZT thin films derived by laser ablation for use in micro actuators is possible.

In this report, Silicon wafer based multi-layered print circuit board is presented. The developed stacked circuit board will lead to realization of 3 dimensional MEMS packaging. The through holes and trenches were formed by ICP Si deep etching and the stacked layered structure was prepared with Si fusion bonding of ICP etched wafers. Metal was filled into ICP fabricated through holes and trenches to make electrical feed through. Four Silicon wafers with ICP through holes are aligned and successfully joined by fusion bonding. The target application of this work is multi-layered Silicon based print circuit board. The electrical feed through was fabricated by injecting the Ag (80 wt%) + Cu(20 wt%) mixed with binder, low melting temperature metal, and Ag electrical conductive paste into the small diameter through holes and trenches in oxidized Silicon wafer stacked structure. A multi- component binder system comprising of EVA (Ethylene Vinyl Acetate 35 wt%) + PW (Paraffin Wax 65 wt%) was used. Super critical debinding method is applied prior to final sintering process. The ratio of metal powder and binder was optimized. Low melting point metal and electrical conductive paste filling methods were also tried by injection and vacuum extraction. SEM observation shows that the through holes are filled with metal for a single wafer. However we have still difficulty in filling the metal into four wafers stacked layer. The electrical conductivity test was sufficient between top and bottom. Several feed through formation methods have been proposed.

This paper develops a sputtering-induced surface roughness model. The model is necessary to control surface roughness of a replicating tool that is machined by focused ion beam (FIB). The significant Gaussian intensity level of FIB profile is determined first, the mathematical model of surface roughness is then developed. The surface roughness function is the combination of the beam function and the material function. The beam function includes ion type, acceleration energy, ion flux, ion beam intensity distribution, tailing and neighboring of the successive beams, and dwell time. The cumulative intensity at a location is calculated by the algebraic summation of individual beam intensity delivered to every pixel successively. The material function includes the inherent material properties related to the ion beam micromachining, such as crystallographic structure and orientation, atomic density, binding energy. Experimental data for silicon verifies the validity of this model.

Handling, assembly and testing in the micro-scale is an important research area. The solutions on how to handle and assemble microparts mainly smaller than the dot on the 'i' in this text can only be achieved by an international consortium of partners, each having large experience and expertise in different but complementary technical or scientific fields, with the industry and partners with commercial activities in the background taking an active role by providing directions according to their requirements. This paper describes some scientific highlights and training activities of HAFAM (Full title: Handling and Assembly of Functionally Adapted Microcomponents), a European network within the EC Programme 'Training and Mobility of Researchers.'

Lead zirconate titanate (PZT) has been used in microsystems because of its high piezoelectric properties. We have succeeded in developing a beam and mirror scanner actuated by sol-gel deposited PZT ([Pb(Zr,Ti)O₃] thin films as in our previous work. However, the problem of residual stress, which was observed in all fabricated devices, has not been solved yet. In this study, we developed a scanner actuated by double layered PZT to compensate for the residual stress and gain greater actuation force. The PZT layer was prepared by the sol-gel technique. The crystal orientation of the PZT films showed a strong (111)texture, which was reported to have good dielectric and ferroelectric properties in our previous work. The devices were fabricated through thin film depositions, lithography, dry plasma etching, and ICP releasing processes. By comparing with the conventional single layer PZT structure, the residual stress can be reduced in the double layered PZT structure. For a one dimensional bimorph beam scanner, an optical scanning angle of approximately 45- degree was obtained at a resonant frequency of 4.25 kHz, which is much larger than the one actuated by a single layered PZT unimorph beam scanner.

The work we present here deals with the use of microstereolithography ((mu) SL) to produce solid freeform objects from computer-assisted-design files. (mu) SL process is derived from stereolithography, and it is based on the photopolymerization through a dynamic mask generator of successive layers of photocurable resin, which permits to produce accurate micro-objects with high aspect ratio and curved surfaces (due to the layer-by-layer nature of the process). This technology is extended to the manufacture of ceramic-polymer composite parts. To achieve this, we add dispersed alumina powder (at a volumic percentage of 24%) and a visible photoinitiator to a low viscosity diacrylate resin. The object we made present interesting properties for microrobotic or microfluidic applications.

This article presents an innovative micromachined silicon device with an electrostatic actuation and a capacitive detection. This device, which is no temperature dependent and shows no hysteretic distortion, is a free standing membrane with four coplanar electrodes in close proximity for the lateral displacements and a parallel electrode for the vertical displacement. The use of phosphorous doped silicon allows the application of an electrostatic force between one electrode and the moving diaphragm. The deep micromachining of the actuator and the electronic detection which gives way to a mechanical sensitivity below 1 angstrom/(root)Hz are presented. The sub-nanometric control of such a membrane with a very low calorific capacity and a relative large area allows new applications towards the scanning thermal microscopy.

A new type pressure sensor based upon an electro-thermally driven and piezo-resistively sensed SiN-beam resonator is presented. A finite element analysis (FEA) method is involved to analyze the relationship between the excitation power, thermal stress, applied pressure and the resonant frequencies of the beam. The sensor is fabricated using silicon micro- machined technology and fusion bonding. Measurements yield a fundamental frequency of about 85 kHz and Q-factor of 1000 in air at atmospheric pressure, rising to over 40,000 in high vacuum (<0.01 Pa). A special close-loop detecting technology is employed to measure the response of the resonant frequency at different applied pressure loads. A 0 - 400 kPa sensor has a good linear frequency/pressure relationship. The span is about 10 kHz over the full pressure sweep, and the pressure sensitivity is about 23.8 Hz/kPa.