Optical scanners and switches are presented as examples of microactuated optical devices. Also a 3D chip-level packaging technique that is capable of optical, mechanical and electronic connections is discussed.

The long term impact of MEMS technology will be in its ability novel sensing and actuation functionality on traditional computing and communication devices enabling the ubiquitous digital computer to interact with the world around it. The design of such integrated system will occur at the system level, driven primarily by the application. Methodologies that ease the integration of the digital domain to the real world using mixed domain technologies are therefore crucial. A hierarchical structured design approach that is compatible with standard IC design is outlined. It starts with schematic capture of a design topology, followed by behavioral simulation, layout generation, parasitic extraction, and final verification. This flow is based on a process-independent design representation of commonly used MEMS building blocks, and process-dependent materials properties, design rules, and parasitic parameters.

Simulation and design of microfluidic systems requires various level models: high-fidelity models for design and optimization of particular elements and devices as well as system-level models allowing for VLSI-scale simulation of such systems. For the latter purpose, reduced or compact models are necessary to make such system simulations computationally feasible. In this paper, we present a design methodology and practical approach for generation of compact models of microfluidic elements. In this procedure we use high-fidelity 3D simulations of the microfluidic devices to extract their characteristics for compact models, and subsequently, to validate the compact model behavior in various regimes of operation. The compact models are generated automatically in the formats that can be directly used in SPICE or SABER. As an example of a nonlinear fluidic device, the generation of compact model for 'Tesla valve' is described in detail. Tesla valve is one of the no-moving- parts valves used in micropumps in MEMS. Its principle of operation is based on the rectification of the fluid, so it may be considered as a 'fluidic diode'.

This paper present a tool and a method for the generation of reduce order thermal models, in order to assure modeling the effect of the package on the thermal behavior of the packaged device. The method is generic, and can be based either on the simulated or on the measured thermal transient response of the real packages. It is based on the generation of the time constant density spectrum of the thermal response function, from which we automatically generate a reduced order thermal model in the form of an RC ladder network model. Beyond presenting the generic methodology experimental results are also presented, based both on the simulation and measurement of MEMS elements and packages.

System designers need access to high-fidelity behavioral models in order to simulate system of MEMS, electronics and packaging. Therefore, the need exists to create behavioral models that provide accurate harmonic and time-domain solutions in a fast and efficient manner. In the MEMSCAP MEMS design suite, the EDD family of tools enables the generation of non-linear dynamic behavioral models from models with a hierarchically lower level of abstraction or measured data. In this paper, we report on a new module of EDD, the ANSYS ModelBuilder, which is embedded in the ANSYS Multi-physics tool set. The module reduces the dimensionality of FEM models built in ANSYS and writes them in popular modeling languages such as HDL-A, SPICE, VHDL-AMS and Verilog-A. We illustrate the capabilities of our new tool by utilizing it to develop two system level examples and compare the results to the full 3D descriptions.

Design of springs is a very important step in the design process of inertial sensor. A procedure for computing the sprint stiffness for any single-chain configuration of beams and a translator which converts beam-based schematic representation of inertial sensor to higher-level behavioral representation are implemented. Combining the spring stiffness computation with the translator, sprint-mass behavioral models of inertial sensor are generated. The behavioral representation is used for rapid design-space exploration. Simulations of the higher-level behavioral representation is used for rapid design-space exploration. Simulations of the higher-level behavioral schematics are 10 to 100 times faster than simulation of the atomic-elements based schematics and the result match to within 5 percent.

In this paper, we present an optimization method for passive components such as straight waveguides, Y-couplers or microring resonators, in order to design optical interconnects and networks. We show that the optical interconnects used in telecommunication applications may also be used in photonic integrated circuits, especially in the case of parallel computing networks. In a first approach, we have taken an interest in modal constant propagation in order to describe signal transmission in integrated optical devices. In a second approach, FDTD simulations of Y-couplers have allowed us to optimize the shape of such devices, and to establish a behavioral model for a single-mode coupler. Moreover, a link between VHDL-AMS and the FDTD algorithm has been prosed in order to overcome problems encountered in the description of propagation phenomena at device and layout level.

A variety of flip chip technologies are available today which differ in bumping material, substrate type, pad metallization and joining method. They are found in packages as well as on multichip modules and directly flip chip bonded on the board. Components including flip chip like bal grid arrays and chip size packages are introduced. Flip chip is the most favored assembly technology for high frequency applications due to the small parasitic of the short bump interconnect. High performance packages for optoelectronic devices using self-alignment during a fluxless reflow soldering are shown as well as the integration of MMICs. High density multichip modules have been fabricated for large pixel defectors of a nuclear detector with eight Chips and more than 46000 I/Os with an acceptable yield. Flip chip technology is a very flexible assembly method for different applications. Variations of the bump structure can be used for MEMS packaging as well and it was demonstrated by the assembly of a thin membrane to form an absolute pressure sensor with a vacuum enclosure. For different packaging requirements the appropriate technology should be chosen very carefully. An overview will be given for different bumping and flip chip joining methods suitable for high volume production as well as for prototyping. Wafer bumping methods will focus on electro less deposition of nickel/gold as well as on electroplating of gold, SnPb and AuSn solders. For rapid prototyping single chip bumping methods are described. Examples of different joining methods - soldering, adhesive bonding and thermocompression bonding - will be shown.

The aim of this work is to analyze the thermo-mechanical stresses evolution produced during the fabrication sequence of the multi-level UTCS structure. Several non-linear material models have been taken into account during the process of modeling. We have therefore resorted to the Finite Element Method for the evaluation of such thermo- mechanical stresses that appears in the manufacturing and stacking process. These efforts are made to optimize the product and process design.

A new vertical chip integration is proposed, based on the UTCS concept. It consists in stacking thinned chips on top of a silicon substrate. Lateral and vertical metal interconnections and the thinned chips are embedded in BCB layers. This wafer scale integration technique is presented. Thermal behavior of such stacked structure is also discussed.

Micro machined relays provide switching solutions that are advantageous over existing technology in many aspects of device performance. In order to fully benefit from the MEMS solution n switching, however, a general integration strategy to various integrated circuit electronics needs to be developed. We describe the design and test of such an integration scheme utilizing flip-chip bonding of MEMS relays onto another substrate carrying the remainder of the circuitry. Individual devices consists of cantilever-like mechanical structure carrying a mobile electrode that is electrostatically actuated. The presence of a second substrate in the flip-chip bonded geometry provides the unique possibility of placing electrostatic actuators on both sides of the cantilever, thereby allowing active turn- on and turn-off of the relay device. The fabricated relays show switching time as short as 10 microsecond(s) , actuation voltages as low as 25V, on-state DC resistance as low as 2 (Omega) and open-state DC resistance as large as 10¹³ (Omega) . The device is assembled and packaged using a single-step flip- chip bonding process. Upon flip-chip bonding, the MEMS devices are completely enclosed in a small cavity between the two substrates that is sealed by a ring-type solder seal. Such techniques provide the opportunity for the integrated chip to be further packaged using conventional cost-effective packaging techniques.

The LC series resonant circuit can be used to obtain large electrostatic forces at relatively low AC voltages. This makes LC derive attractive for electrostatic actuation and force feedback. It can also be used for achieving large displacements of a micro mechanical plate capacitor either by sweeping the frequency or the amplitude of the driving AC voltage. In both cases relatively good linearity can be obtained. The minimum driving voltages and maximum driving speeds are discussed. It is found that the LCR drive can tolerate relatively large parasitic capacitances. measurement done on a dual capacitive acceleration sensor verify the calculated results. A drive AC voltage rms amplitude of 10 percent of the DC pull-in voltage deflected the moving plate by about 60 percent of the nominal gap, limited only be a mechanical stopper.

The aim of this work is that of evaluating the relative contribution of the different non-linearities in the simple case of slender cantilever beams and plates under electrostatic loads. This case not allows analytical solution to be achieved and therefore a numerical approach must be followed. Multipurpose commercial software do not feature simultaneous solution of electrostatic and structural problems. In this work a solution algorithm for the coupled electro-mechanical system to be implemented in a finite element commercial software is prosed. The solution follows a Newton iterative method in which the solution of the linear system is obtained through the biconjugate gradient stabilized method. This approach is compared with the already proposed relaxation scheme. The 2D case was firstly considered taking into account the contribution of the fringing field on the tip of the beam. In order of evaluate the accuracy of such a model a 3D model has also been developed taking into account the fringing field on the lateral surface, the anticlastic curvature of the beam and the lateral effect of the constraint. The result obtained emphasizes the coupling between electrical and mechanical solution as an error around 30 percent is obtained if the mechanical solution is calculated on the base of the undeformed electric field On the other hand the 2D mode gives a suitable model of the structure as an error of the order of 2.5 percent with respect to the 3D case has been obtained.

Suspended thermal MEMS is one of the major domains of application of CMOS-compatible bulk-micro machining technologies. In some applications, a tradeoff much be reached between the mechanical strength of the micro structure and the thermal losses through the support beams. This paper illustrates how suspended MEMS can be strengthened by means of additional support beams which have a very high thermal impedance, thus having a very small impact in the thermal behavior of the micro structure. A high thermal impedance beam can be considered as a new MEMS design cell. The use of this cell in the design of an electro thermal converter with long time constant is illustrated.

Manufacturing test structures of microsystems is a very expensive process, both in terms of time and money. For this reason, computer—supported design technologies ensuring continuous support in all design phases and, consequently, also consistency, are becoming increasingly important in microsystems technology. The modular structure of hybrid systems requires single components to be manufactured in isolation and later combined into one total system. Combining single components into one overall system is bound to be subject to certain tolerances. The concept presented in this paper is the computer—aided design of a modular system rugged enough to be employed in mass fabrication. In mass fabrication, it is not the ideal arrangement of individual components which results in the most effective system. Instead, tolerances in positioning individual optical elements need to be taken into account already in modeling. Furthermore environmental influences like e.g. variations of the temperature can have an impact on the performance of the micro—optical function module.

A low-cost open loop differential capacitive accelerometer with a resolution of 5mg and high sensitivity has been designed with a ful measurement range of +/- 2g. By using the single crystal reactive ion etching and metallization process, beams with high aspect ratio, small air gap for large capacitance variation and low parasitic capacitance have been attained. The fabricated micro accelerometer also offers high voltage output and it has successfully survived a shock of 1000g. The effects of electrostatic spring constant on the natural frequency and sensitivity of the accelerometer have been thoroughly discussed, and obliqueness of the beam cross-section has also been taken into consideration. The radiometric error for this system has been optimized and is well below 2 percent with a cross axis sensitivity of less than 3 percent. The operating voltage is 5V DC. The construction is based on a hybrid two- chip design and the sensing element is wire bonded to a CMOS ASIC.

A new fully silicon MEM technology and design methodology is introduced to realize millimeter-wave applications such as switches. It is based on two kinds of micro-machining techniques: a bulk micro-machines used to realize micro-wave circuits on a suspended membrane in order to decrease losses, and a surface micro-machining to make air-bridges actuable by electrostatic force. A MEM bridge electrical model has been investigated and implemented in the design of distributed switches.

This paper reports the design, fabrication and packaging of a micro machined silicon/Pyrex based chip for the polymerase chain reaction. Anodic bonding is used for sealing the chambers of 1 (mu) l volume with a Pyrex glass wafer. Platinum resistors on the back of the wafer are used as heaters and temperature sensors. The chip is externally cooled by forced air to achieve rapid temperature cycling. The transparency of the Pyrex makes it possible for using optical readout methods. The packaging is especially designed for easy handling, filling, power connection, temperature regulation and optical readout. The mass production of such silicon reactors could make single-shot, disposable devices economically viable.

A systematic method of synthesis of monolithic mechanical structures called compliant mechanisms is presented. Sophisticated mechanical functions can be realized with these mechanisms and their unitized construction eliminates joint friction, clearances, and the need for assembly.

The design of two microelectromechanical (MEMS) devices that form pat of a micro acousto-magnetic transducer for use with a hearing-aid instrument is described in this paper. The transducer will convert acoustical energy into an electrical signal using a MEMS realization of a capacitive microphone. The output signal from the microphone undergoes signal conditioning and processing in order to drive a MEMS electromagnetic actuator. The resultant magnetic fid is used to exert a force on a high coercivity permanent micro magnet that has been implanted on the round window of the cochlea. The motion of the implanted magnet will develop traveling waves on the basilar membrane inside the cochlea to give a hearing capability. A high-sensitivity MEMS based capacitor microphone is designed using a polysilicon Germanium diaphragm. The microphone is constructed using a combination of surface and bulk micro machining techniques, in a single wafer process. The microphone diaphragm has a proposed thickness of 0.7 micrometers , an area of 2.6 mm², an air gap of 3.0 micrometers and a 1 micrometers thick silicon nitride backplate with acoustical ports. An output voltage signal is obtained from the capacitor microphone using a capacitive voltage divider network and amplified by a simple source follower circuit. D

This paper reports on the mathematical modeling on the quadrature error of a micro gyroscope due to the imbalance of the flexures. Quadrature error occurs when the proof mass of a micro gyroscope oscillates along an axis that is not exactly parallel to the X-axis. The asymmetric spring flexures due to manufacturing variation can cause the proof mass to rotate when a force acts on the proof mass. The mathematical mode is verified using finite element software, Intellicad and found to have a good agreement with the simulation results for angles of rotation of comb fingers below 5.26 degrees. The mathematical model provides a new avenue of approach in solving the quadrature error problem and in saving the overall simulation time. The spring constant of the fishhook flexure can be calculated form Castigliano's energy theorem and substituted into the mathematical mode to find out the size of the quadrature error. The sensitivity of a fishhook flexure to its dimensions is analyzed.

CMOS image sensors are now becoming the technology of choice for most imaging applications, such as digital video cameras. The spatial field, in particular, is being interested in this new kind of sensor because of its low cost, its multiple functionalities, and its performances in terms of readout frame rate and sensitivity. For this, a new kind of CMOS image sensor has been introduced in order to be used in a star tracker for satellite.

Matrices of binary micro-lenses monolithically integrated with the focal-place-arrays (FPA) of longwave IR uncooled detectors can significantly improve sensor's parameters. Surface relief of the binary micro-lenses is built of annular stair step structures of heights and widths smaller than the radiation length. Scalar diffraction theory cannot correctly describe diffraction on these micro-structures and therefore the rigorous electromagnetic theory should be applied. In this aper, we have applied the electromagnetic eignemode method to study binary micro-optics for the longwave IR FPA of 50 micrometers pixel width. We have shown that binary refractive micro-lenses outperform their diffractive counterparts allowing for detectors of 10 micrometers width. The effective refractive micro-lenses require the 8-level surface relief. Geometrical optics predictions of the focal position agree quite well width electromagnetic calculations.

A light and fast 2-axial fine-pointing mirror has a number of space applications, especially in intersatellite optical links. The fine pointing of laser beams in optical links is currently realized with electromagnetic and piezoelectric actuators, which are relatively large and heavy. MEMS technology bears a high potential in space applications offering reduction of device size, mass and power consumption. Micro technology makes batch mode fabrication possible yielding a low cost per unit. VTT Automation has designed and partially tested a silicon micro machined electrostatically actuated 2-axial mirror, which can be controlled with a microradian accuracy and a large bandwidth over the angular range of +/- 3 mrad.

We present a packaged micro resonator for static load measurement under high temperature, performing with high precision and a resolution better than 100 ppm. There is an industrial need for such measurement tasks, however, such sensing cells are not available so far. To minimize temperatures stress we developed an all-in-silicon, in difference to micro machined resonant force sensors, which have been published. We propose a force sensor where load coupling, the excitation and detection of the vibration of the micro resonator are integrated in one and the same single crystal silicon package. The complete single crystal design together with a fiber-optical on-chip detection method will allow measurements at high temperatures. A considerable degree of freedom for the resonator's shape design, as needed for the investigation of filer mechanisms, is given by a DRIE fabrication method.

This paper presents the concept and design of a new lateral scanning system for an integrated atomic force microscope (AFM). The core part of the scanner is formed by vertical bimorph beams, which are reported for the first time in this paper. They consist of silicon beams side-coated with aluminium, which bend upon heating causing movement in the horizontal plane. Combining vertical bimorphs with planar bimorphs allows three-dimensional actuation. Theoretical analyses comprising electro-thermal and thermo-eleastic calculations show that large actuation movements are possible at low electrical input power and low input voltage. A process has been developed to deposit aluminium onto sidewalls of silicon beams. Furthermore, the fabrication process for the actuator is described.

In this paper we intend to introduce a new magnetic field sensor. The sensing principle is based on the deformation of a mechanical structure due to magnetic forces, using ferromagnetic materials. Thus the sensor can be classified in the passive sensor category and exhibits very low power consumption, only due to conditioning circuit. The sensor is designed for monolithic integration with CMOS electronics. Post-process fabrication steps are described and experimental results, obtained on a torsion structure are shown. The sensitivity of this new sensor compares with that of highly sensitive Hall plates. A simple analytical model is finally given and turned into analog VHDL description in order to fully integrate the sensor in the standard microelectronic design flow.

An interface circuit in a 0.8-micrometers CMOS process for the on- chip integration of a capacitive micro-sensor used as a microphone is presented. In order to circumvent 1/f noise contributions and to improve the signal/noise ratio, a synchronous modulation-demodulation technique has been applied. For the implementation of this technique, we have studied and designed several functional block, such as modulator with signal conversion, low-noise amplifier, demodulator, etc. To deal with problems related to dispersion of intrinsic capacitance of the sensor, a feedback compensating solution is suggested. The designed circuit has a sensibility of 1200 V/pF, with a minimum detectable capacitance variation of 2 10^-6 pF.

A magnetic field-to-voltage converter using a magnetic MOSFET devices has been designed, simulated and tested. The resulting sensor was measured under magnetic fields ranging from 0 to 0.8T, the obtained sensitivity was 0.03T^-1 with an offset lower than 0.2 percent. SPICE macro model for the MAGFET in the saturation region is presented. Also, we have simulated the behavior of the specific A/D system, based on a current-mode technique, making use of high description language.

In this work, the design of RF VCO circuit, in which the oscillation frequency is controlled by a tunable capacitor based on microelectromechanical system (MEMS) technology is presented. The design of high Q-MEMS tunable capacitor has been accomplished through bulk micro machining with all metal micro structure. A standard CMOS process is used to carry out the fabrication of the VCO circuit with the MEMS tunable capacitor on the same chip. The main features of this design, is the enabling of a complete monolithic fabrication RF VCOs using on-chip IC compatible high-Q MEMS tunable capacitor. The performance of the MEMS capacitor is modeled with emphasis on the tunability range with the tuning voltage. The simulation results are presented to show the performance of RF VCO circuit with the MEMS tunable capacitor, which has a high-Q of about 60 at 1 GHZ and low insertion loss of -1dB at 40 GHz.

The integration of small arrays of c-Si photovoltaic devices using a flip-chip Multichip Module technology is reported. A number of arrays made of 15 series-connected 2mm² photovoltaic cells have been assembled, achieving a packaging density of 40 chips/cm². Different cell geometries and several fabrication details have been investigated. Preliminary measurements of the dark characteristics are shown with good ideality factor values, thereby indicating that the interconnection of the devices did not jeopardize the properties of the individual cell. More than 6.5 V in open circuit conditions were typically measured, and simulations showed that for monochomatic illumination in the IR region above 60 mA/cm² could be achieved for 100mW/cm² of incoming light. Exposure to commercial IR lamp placed at 4cm distance from the miniarray generated approximately 1mW of power at 6.5V.

We discuss concurrent multiscale simulations of the dynamic and temperature-dependent behavior of sub-micron MEMS, especially micro-resonators. The coupling of length scales methodology we have developed employs an atomistic description of small but key regions of the device, consisting of millions of atoms, coupled concurrently to a finite element model of the periphery. This novel technique accurately models the behavior of the mechanical components of MEMS down to the atomic scales. This paper addresses general issues involved in this kind of multiscale simulation, with a particular emphasis on how finite elements can be extended to ensure a reliable model as the mesh spacing is refined to the atomic scale. We discuss how the coupling of length scales technique has been sued to identify atomistic effects in sub-micron resonators.

The latest advances in MEMS technology have enabled the design of a new generation of electronic microsystems products. These systems may combine numerous analog/mixed signal microelectronics blocks and MEMS functions on a single chip or on two or more chips assembled within an integrated package. As designers have begun to use CAD tools to insert MEMS into these new products, additional requirements and constraints on the tools are emerging. As the MEMS designs move from prototypes to manufacturing production new CAD issues emerge.

In this work, a new fully automated geometrical modeling and meshing tool is described. It imports standard layout formats, images, and 3D boundary representations s. A 3D model is then generated by simulating 3D operations specified by the process data or the user. A 3D finite element mesh with tagged boundary and volume conditions is then automatically created. The automatic generation of 3D model and mesh takes typically a couple of minutes on a current PC machine. The paper will present the geometry/meshing engines, user interfaces, and will demonstrate them on a range of microsystem applications.

A CAD-integrated total design system for MEMS is developed which can perform analysis and design for mechanical performance of a MEMS structure. The software works in a parametric CAD platform and makes users to do from CAD modeling and analysis to design optimization. Basic philosophy is to assure robustness, versatility and user friendliness. To satisfy these requirements; 1) Design variables are selectable directly form CAD model, 2) Commercial codes are utilized as many as available, and 3) Design sensitivity analysis must be simple and robust. Commercial finite element codes and some newly developed modules are integrated in the system for analysis. For design sensitivity analysis, two approaches were implemented: finite difference method and the Taguchi method. The approximate methods adopted seem to be simple and robust, which can be applied to design of complex practical structures. The design sensitivity analysis by finite difference method, with nonlinear programming and trade-off study, gives satisfactory results. The Taguchi method module is integrated for robust optimal design of MEMS structure. Although it is not meant to find the exact optimum point, it is applicable to practical problems where performance characteristics are hard to evaluate, since this does not require any derivative information. Two examples are taken to examine performance of the developed design tool and proposed methodology. It relieves much of the difficulties often met in conventional design works and has shown practicability for structural design of MEMS.

We employ Modified Nodal Matrix representation, piecewise linear modeling of non-linear devices, and piecewise characterization of signals to accomplish the simulation of mixed technology system. Piecewise simulation modeling for both optoelectronic and mechanical devices is used to decrease the computational task and allow for a trade-off between accuracy and speed. The extraction from device level simulation of circuit models, which characterize high level effects in optoelectronic or mechanical devices, allows for the inclusion of these effects into traditional circuit representations for the device. This technique improves the overall simulation accuracy without compromising the efficiency of the simulator. The additional advantage of using the same technique to characterize electrical and mechanical models allows us to easily merge both technologies in complex devices that interact in mixed domains.

This article sets out to first recall some of the major principles of standardization and to identify the main areas of MST where standards would be beneficial. It then sets out to identify the main organizations presently involved in standardization activities.

This paper focuses on the production scheduling in MEMS manufacturing. The whole MEMS production process can be broken into 3 sub-processes, i.e., the front-end process, the wafer cap process and the back-end process. Every wafer processed by the front end process needs to be bonded with a wafer cap that are manufactured by the wafer cap process, and then it will be sent to the back-end process. Therefore how to synchronize the release of wafers into the front end as well as the wafer cap process becomes an important topic. An ineffective coordination will create larger WHIP and longer cycle time. In this paper, four different synchronization rules are developed and they are evaluated together with seven dispatching rules. The performance measures considered are cycle time, throughput rate and WHIP. A visual interactive simulation model is constructed to imitate the production line. The simulation results indicate that the synchronization rules have more significant impact than the dispatching rules on the performance of MEMS manufacturing.

The Center for Advanced Micro structures and Devices (CAMD) at Louisiana State University supports one of the strongest programs in synchrotron radiation micro fabrication in the USA and, in particular, in deep x-ray lithography. Synchrotron radiation emitted form CAMD's bending magnets has photon energies in the range extending from the IR to approximately 20 keV. CAMD operates at 1.3 and 1.5 GeV, providing characteristic energies of 1.66 and 2.55 keV, respectively. CAMD bending magnets provide a relatively soft x-ray spectrum that limits the maximal structure height achievable within a reasonable exposure time to approximately 500 micrometers . In order to extend the x-ray spectrum to higher photon energies, a 5 pole 7T superconducting wiggler was inserted in one of the straight sections. A beam line and exposure station designed for ultra deep x-ray lithography was constructed and connected to the wiggler. First exposures into 1 mm and 2 mm thick PMMA resist using a graphite mask with 40 micrometers thick gold absorber has been completed.

In the macroscopic world different 'rapid'-technologies like Rapid Prototyping, Rapid Manufacturing or Rapid Tooling have been established for a fast prototype or molding tool development. In all cases CAD-data can be transformed in a model or prototype directly using a laser which polymerizes reactive resin layer by layer to a final 3D mold within a short period. In this work the rapid fabrication of micro components made from polymers or composites will be presented. The whole fabrication process is divided into two main steps: Firstly laser assisted micro machining using Nd:YAG and KrF-Excimer laser allows a rapid manufacturing of micro structured cemented carbide or steel mold inserts. Secondly the application of light induced reaction injection molding using reactive monomer/polymer resins gives access to the replication of the previously fabricated mold insert. The total processing period starting from CAD until the modeled micro structured part is less than one week.

This paper will focus on the technical challenges that arise in the in-vivo monitoring, detection and treatment of cardiovascular diseases using MEMS. The packaging and wireless telemetry issues will be discussed at length.

MEMS structures rendered defective by particles are modeled a tthe scehamtic-level using existing models of fault-free MEMS primitives within the nodal simulator NODAS. We have compared the results of schematic-level fault simulations with low-level finite element analysis and demonstrated the efficacy of such an approach. Analysis shows that NODAS achieves a 60X speedup over FEA with little accuracy loss in modeling defects caused by particles.

The emerging MicroElectroMechanical Systems (MEMS) technologies are entering in an active phase of high volume production and successful commercial applications. The expertise and the qualification for space application of such devices have already begun. But these technologies are still recent and important efforts on the reliability issue have to be done. This paper defines the role oftechnological analysis in the actual MEMS design process. Afterwards, it presents MEMS technological analysis techniques developed at CNES applied to an open MEMS technology. In particular, it is shown how these technological analyses respond to designer needs and that the designer and the founder still need a strong interaction. We also present the MEMS reliability issue at CNES and replace it in the current world's one.

The emerging MEMS technologies are entering in an active phase of high volume production and successful commercial applications. The expertise and the qualification for space application of such devices have already begun. But these technologies are still recent and important efforts on the reliability issue have to be done. This paper defines the role of technological analysis in the actual MEMS design process. Afterwards, it presents MEMS technological analysis techniques developed at CNES applied to an open MEMS technology. In particular, it is shown how these technological analyses response to designer needs and that the designer and the founder still need a strong interaction. We also present the MEMS reliability issue at CNES and replace it in the current world's one.

Pressure sensors structures have been fabricated in a commercial CMOS foundry technology using a post-processing for back-side wafer micro machining. In order to predict the sensor response to an externally applied differential pressure, the structure behavior has been simulated by Finite Element Methods. The design and fabrication of test structures for these sensor devices is described. Experimental results obtained using these structures are presented.

Ink jet nozzles require accurate definition and smooth surface finish to promote laminar flow of ink and prevent turbulence. Recent investigations into micro-electro discharge machining of nozzles in thin stainless steel have shown that surface finish is dependent not only on machining parameters but also on material selection and quality. Defects within the material such as cracks, aligned to the direction of rolling, are a source of random defects within nozzles after machining. They can cause severe problems by acting as sites for ink-flow perturbation and corrosion and thereby cause defective printing. Evaluation of material quality at the microscopic level prior to machining is therefore recommended to avoid a waster of machining-time on sub-standard material and the resultant low yield of acceptable nozzles. Image analysis of a range of materials has shown that some materials examined contained relatively few defects.

It has been observed in many MEMS devices that there is a shift in resonant frequency due to voltage bias. The voltage bias may include either AC or DC bias or both. This paper reports on the significant discrepancy between the analytical and experimental resonant frequencies of folded beam micro resonators. Experimental results for the resonant frequency showed a consistent 20% discrepancy over theoretical and finite element results for MUMPs fabricated resonators. This difference in frequency is also seen in SOl fabricated devices. Possible causes of the discrepancy from tapered cross section of the flexure beams, dimensional variations and electrostatic spring effects are discussed and shown to contribute to the significant difference between analytical and experimental values. Inte11iCADTM electrostatic simulation was done to isolate the electrostatic spring effect and compared with the experimental observations. The compliance due to AC voltage has also been observed in SOl and MUMPs resonators and has been presented.

In this paper two different packaging and testing approaches were studied for Si based microphone. Microphone performance was tested with Ceramic, Plastic and metal packages. Sensitivity testing of microphone is done when it is connected to an ASIC die. Testing was done with microphone and ASIC packaged separately and also in a single package. Substantial noise was generated when microphone and ASIC are tested separately in a PCB. Noise was detected after 150 Hz with the noise intensity reducing as it goes to higher frequencies. This was observed regardless of the packaging schemes. Different shielding methods were tried and found that copper foil shielding results in substantial noise reduction during frequency response testing and a flat response curve was observed with metal can package. Form this new testing methodology, it is demonstrated that same ASIC can be used repeatedly during microphone testing and hence some cost reduction can be expected.

A number of methods for torque measurements in the macro domain exist, but only some of them can be scaled down to micro dimensions. This paper describes one method for measuring very small moments which is based on the measurement of torque by using silicon micro springs. Three different designs of torsion micro springs have been produced. The experimentally measured results show the possibility of torque measurement in the sub-(mu) Nm range.

This paper describes a study of the failure of polymer-metal interfaces in plastic-encapsulated IC packages subjected to hygro-thermal loading during solder reflow. All the analyses performed are under plane strain conditions. A finite element fracture mechanics approach was employed to predict the temperature at which a small delamination in the polymer-metal interface of an IC package will propagate. In order to confirm the accuracy of the above prediction, actual package specimens were fabricated and subjected to various levels of moisture preconditions followed by thermal loading at varying temperatures. The specimens were then examined to determine the temperature at which the interface failed. Good agreement was found between numerical prediction and experiment.

International Frequency Sensor Association (IFSA) is non- profit association, create din 1999 year with the aim to promote research, development, production and application of modern sensor with frequency or digital output throughout worldwide, thus preparing industries for the world market in this promising field. This objective can be achieved by both simulating the information exchange and dissemination through the Internet, and the creation of strong links between industry and research. Presently, IFSA comprises 48 percent industry members and 52 percent academia members form 16 European and Asian countries and USA. This paper describes the IFSA and gives an overview of its specific activities.

Literature provides a sufficient body of information on developments of electrostatic micro relays (EMR) with movable electrode (ME) in the form of a spring cantilever beam. However, little attention has been given to obvious close relationship between required characteristics and the corresponding design solutions of EMR components, which hinders the development of relay constructions optimal for specific working conditions. This paper presents a method for determining values and interrelations of electric and mechanical parameters of EMR's promising for certain applications. Schematically, the EMR consists of a rigid dielectric substrate 1 having a salient part 2 covered with a deposited stationary thin-film electrode (SE) 3 and spring plate 4 upon which a cantilever ME 5 is placed in the area hanging over the salient pat. Contacts 6 of control circuit are located at the electrode ends.

Design verification methodologies and tool such as DRC and ERC used on MEMS design have been inherited from the transistor based analog and digital full custom design flows. However the devices are defined on a 2D layout, they have a 3D structure. Thus, current tools do not have into account the new features that appear in MEMS design, especially those related with device micro machining. The main consequence on it is that it is necessary to include information of the vertical parameters on the DRC, what is not at all usual in classical design. We claim that the inclusion of such information together with the consequent improvement of tools for DRC, ERC and device parameter extraction, can reduce design and simulation efforts as well as improve the manufacturing yield.

This paper presents a framework for modeling essentially 1D devices and components embedded in multi-dimensional spaces. The main characteristic and main advantage of the new methodology is that the 1D and multi-dimensional objects or domain are meshed completely independently of each other, without regard to their relative alignment or location, and subsequently combined into a single, unified composite mesh. The coupling of the solution between the different domains is handled fully-automatically in the solver, entirely through exchange of source terms between these domains of differing dimensionality. The source terms are evaluated locally on a cell-by-cell basis, depending on the solution values in these domains and the manner in which the 1D grids intersect the multi-dimensional grids. The capabilities and usefulness of the method are demonstrated with several examples.

This paper aims at proposing a new enhanced way of working in electronic design. In fact, the design of an electronic component requires many competencies and skills, and the joint effort of several researchers and engineers, not necessarily located a the same lace. With traditional ways of work and communication tools, the interactivity level is reduced and it seems that the product life cycle cannot be improved significantly anymore. As a response, the technological progress in high speed networks and new communication and interaction tools open the way to concurrent engineering. This paper then aims at presenting such way of working, the new functionalities provided to users, and of course the benefits they can gain. As a case study, an actual example in the domain of electronics design illustrates this paper.

Two novel integrated optical detectors called BDJ detector and BTJ detector have been developed in our laboratory. These two detectors have different applications: the BDJ detector elaborated in CMOS process can be used for wavelength or light flux detection while the BTJ detector based on a bipolar structure gives the trichromatics components of a light. To develop microsystems, we need simulation tools as SPICE model. So, we have elaborated a physical mode, proposed a parameters extraction method and study influence of different parameters for BDJ detectors. Simulations and measurements have validated these models. More, we prose a design of BTJ detectors for developing new color imaging systems.

Within this paper we perform a simulation study of the 'bimetal' effects for the silicon-silicon dioxide membrane suspended in different manners. For this purpose, a commercial, COSMOS/M program working with finite element method has been used. We investigated the dependence of the value and orientation of the displacements of the bi-layer type membrane as a function of temperature, temperature gradient, geometrical dimensions, expansion coefficients and type of membrane support. The test structure for this simulation consists of a square SiO₂ membrane of 100 X 100 micrometers ² with 10micrometers for each layer. The connection of the membrane to the bulk silicon was performed by different manners as follows: (i) by four horizontal bridges, (ii) by four vertical legs or (iii) by its four edges. From simulation study, we have obtained the effect of the above variables on the value and orientation of the membrane deformation, as follows: a) The temperature and gradient temperature, layer thickness and rigidity of the material lead to modification of the value displacements of the membrane; b) Type of the membrane support lead to modification of the both value and orientation of t he deformation of the membrane. This study of the membrane deformation can be successfully used for designing a new gas structure based on surface micro machining and hopefully with low power consumption and predicted deformation.

This work relates to a method for increasing the adhesion of polymer resist to electrically conductive substrates which is an important step in the lithographic steps for creating high-aspect-ratio micro structures. Here we are particularly interested in plating Ni-Co into the very tall high-aspect- ratio accurately patterned polymethyl methacrylate (PMMA) micromolds. They were made by deep x-ray lithography for primary or secondary metal structures or metal mold inserts within the framework of the LIGAS process. We investigated the effect of using a Novolak intermediate layer on various substrates to consolidate the adhesion of the relatively weak PMMA-metal interface. Modifying our process by introducing this intermediate Novolak sublayer improved the adhesive properties overall throughout the whole process including the planarization step, leading to a more reliable process with better yield as well an increase in the quality of the Ni-Co parts. The increase of bond resistance to heat and x-rays was evaluated by shear stress measurements.

A new approach for a practical, easy to implement reliability estimation procedure for microsystems (MS) is presented. The proposed procedure is based on the combined use of a number of reliability data sources, deterministic models and calculation methods for MS components. Some criteria needed to assess the value of a reliability prediction procedure are established. For the first time these criteria are chosen to specific features of MS subfunctions and components. To be obtained realistic test data for all MS component a qualification for them are designed.

A micro machined capacitive silicon scale has been designed and fabricated. It is intended for weighing masses on the order of 1 g at the resolution of about 1 ppm and below. The device consists of a micro machined SOI chip which is anodically bonded to a glass chip. The flexible electrode is formed in the SOI device layer. The other electrode is metallized on the glass and is divided into three sections. The sections are used for detecting tilting of the top electrode due to a possible off-centering of the mass load. The measuring circuit implements electrostatic force feedback and keeps the top electrode at a constant horizontal position irrespective of its mass loading. First measurements have demonstrated the stability allowing measurement of 1 g masses at an accuracy of 2...3 ppm.

In the paper the results about changes of the current- voltage characteristics of the surface-barrier structures (SBS) after the deposition of myoglobin and its specific monoclonal antibodies are presented. It was shown that the SBS structures with ultra-thin films or with ultra-thin layer of the porous silicon are sensitive to the presence of the protein or its specific immune complex on their surfaces. The response of the system depended on the conditions of the specific complex formation. The characteristic optimum of the thickness of Ni film or the layer of the porous silicon was revealed when the changes of the I-V characteristics had a maximum level.

We realized different types of optoelectronic integrated circuits by integrating on the same silicon chip: photo detectors, linear or logic electronic circuits, waveguides, coupling elements. This paper present the design, modeling and experimental realization of these components, underlining the original approaches and results. Special structures of photo detectors were designed, in order to allow optical coupling with waveguides and monolithic integration with electronic and photonic circuits. Original models for these photo detectors were developed. The electronic circuits we realized, unlike those reported in literature, can operate at very low input currents. Also new materials and processes were studied and experimented in order to improve the component performance. Specific technologies for optoelectronic circuits, compatible with either CMOS or bipolar processes, were established by analyzing the relationships between the technological parameters and circuit characteristics. Also the matching with waveguides and micro mechanical structures technologies was analyzed and experimented, as the aim of our research activity was to realize different types of micro-electro- mechanical systems for sensor applications.

New fabrication method of nanoscale regular tips for vacuum microelectronics basing on electrochemical anodizing double- layer systems aluminum-niobium in aqueous acid electrolyte has been developed. This method allows providing very small overall emitted size and high uniform packaging densities without lithography and etching technique. Electron field emission from array of niobium nanotips formed in porous anodic alumina matrix has been investigated.

Ink jet nozzles require accurate definition and smooth surface finish to promote laminar flow of ink and prevent turbulence. We have fabricated ink jet nozzles by three different fabrication ttechniques to evaluate the characteristics of each technique and assess the differences between them. Scanning electron micrographs illustrate the differences between the three types of nozzle produced and these have been quantified where possible. The machining times for these fabrication processes are also compared.

The investigations of photo luminescence spectra of the electrochemically produced porous GaAs layers, excited by continuous Ar laser radiation, were carried out. The chemical composition of the anodized p- and n-GaAs was analyzed by x-ray photoelectron spectroscopy. The GaAs surface morphology was examined by high-resolution transmission-electron microscopy and surface structure was investigated by electronograph EMR100 and Atomic Force Microscopy. It is established that increasing a duration and current density of etching changes the porosity of bulk GaAs and both Galium and arsenic oxides are formed on the sample surface Photo luminescence spectra of investigated porous surface consist of 'IR' and 'green' spectral structures. The 'IR' structure exhibits redshifts of its peak energies, and 'green' structure intensity is dependent on etching conditions. A possible reason of origin and changes in those spectra is discussed.

In this paper, a new surface mount system with parallel arrangement miniature manipulators is proposed for use in system downsizing. The miniature manipulator consists of a molded pantograph mechanism, which is composed of large deflective hinges and links, both made of the same materials. In order to create such systems, first, durability of the pantograph mechanism is to be confirmed by fatigue tests. Next, the input and output displacement characteristics of the pantograph mechanism are to be experimentally discussed. Finally, propriety of the proposed system should be confirmed.

The core of the project has been to design a moveable micro mirror array with the most optimal dependence of the optically active area, the deflection angles and the micro mirror power consumption, while keeping the cost of the chip as low as possible. The matrix of 20 X 20 micromirrors uses an electrostatically actuated principle. The array is designed using the Three Layer Polysilicon Surface Micro machining Process technology. Each micro mirror has two torsion springs and the size of the reflected plate is 70 X 70 micrometers . The penetration of the reflected micro mirror array is about 70 percent. The micro mirror array is addressed by 36 pads that are connected to the top and bottom electrodes. Potential connected between electrodes is used for the actuation of micro mirror. For the first step, we have designed 20 types of micromirrors, which differ in geometrical sizes and thickness of the micro mirror plates. The dilation angle of the micro mirror is 1.7 or 2.3 degrees defending on the type of the micro mirror.

Many polysilicon devices, like comb-drives, micromotors, valves, accelerometers, micromirrors or microshutters use electrostatic forces for their actuation. Electrostatic forces increases with the square of the inverse of the distance between electrodes. Due to this favorable scaling law, electrostatic actuation is interesting for microsystems.

With the conventional micro machining technologies: isotropic and anisotropic, dry and wet etching, a few shapes can be done. To overcome this limitation, both binary multi- tasking technique or direct EB writing were used, but an inexpensive one-step UV-lithographic method, using a so- called 'gray-tone reticle', seems to be the best choice to produce local intensity modulation during exposure process. Although, by using this method and common technologies in standard IC fabrication it is easy to obtain an arbitrarily 3D shaping of positive thick resists, there are some limitations, too. The maximum number of gray-levels, on projection reticle, achieved by e-beam writing, are only 200. Also, for very thick resists, the limited focus depth of the projection objective gives a poor lateral resolution. These are the reasons why the author prose da new approach to enhance the 3D resolution of gray-tone lithography applied for thick resist. By a high resolution, both for vertical direction, as well as for horizontal direction. Particular emphasis was put on the design, manufacturing and use of halftone transmission masks, required for UV- lithographic step in the fabrication process of mechanical, optical or electronics components. The original design and fabrication method for the gray-tone test reticle were supported by experiments showing the main advantage of this new technology: the 3D structuring of thick resist in a single exposure step and also a very promising aspect ratio obtained of over 9:1. Preliminary experimental results are presented for positive thick resists in SEM micrographs. A future optimization of the lithographic process opens interesting perspectives for application of this high 3D resolution structuring method in the fabrication process of different products, with imposed complex smooth profiles, such as: x-ray LiGA-masks, refractive optics and surface- relief DOEs.