In the beginning stage of MITI micromachine project, the committee on the standardization established in Micromachine Center recognized the importance of measurement technique for the promotion and the systemization of the micromachine technology. Micromachine Center is the organizing body for private sectors working in the MITI micromachine project which started in 1991. MITI stands for Ministry of International Trade and Industry in Japan. In order to known the requirements on the measurement technologies, the questionnaire was organized by the measurement working group in the committee. This talk covers the questionnaire and its results, and some research results obtained at National Research Laboratory of Metrology working as a member in the project.

Fabrication- and measurement-induced stresses in surface micromachined structures are investigated by wafer-level probing of electrostatically actuated polysilicon test structures fabricated by the MUMPs process of MCNC. The test structures are based on M-Test, an electrostatic pull-in approach for monitoring process uniformity and reproducibility, and, when used in conjunction with suitable geometric data, for measuring material properties. The sensitivity of the pull-in technique reveals that the simple step of placing the die on a vacuum probe station can significantly affect the measured results. The presence of strain gradients in the polysilicon and compliant structural supports for the beams makes the modeling more complex than for ideal geometries, but with appropriate adjustments to the models, and with knowledge of the strain gradient obtained from cantilever tip deflection as a function of beam length, the technique enables a measurement of the elastic modulus and the fabrication-induced residual stress.

This paper presents recent NIST MicroElectroMechanical Systems fixed-fixed beam test structure data and analysis. These test structures show the most promise in measuring the compressive strain due to simplicity of the test structure design, simplicity of test and analysis, ability to better isolate compressive strain values as a function of geometry, and, most importantly, capability to record process variability data.

Polycrystalline silicon (polysilicon) is widely used as a mechanical layer in MicroElectroMechanical Systems (MEMS). Mechanical elements within MEMS structures are, by design, microscopic in size. Because the thickness of the polysilicon layer is typically around 2 micrometers and the width and length of the freed area is a few to hundreds of micrometers, standard techniques and apparatus for measurements of mechanical properties are not applicable. Furthermore, the deposition techniques for polysilicon cannot be adapted to make specimens big enough to test by conventional techniques. Therefore, special structures were designed to facilitate measurements of Young's modulus and fracture strength: cantilever beams and dog-bone tensile specimens. Here we report first experiences with these structures. These experiences include successes and failures in manipulating and testing the special structures. While no definitive results for either fracture strength or Young's modulus are reported here, some plausible values for both quantities were obtained. Test methods and preliminary results to date are discussed.

Integrated microsystems raise new problems in thermal simulation. The frequently used structures such as cantilevers, membranes have quite different heat transfer properties than the simple silicon cubes of conventional ICs. Furthermore numerous functions are realized on these structures based on thermal principle. Quick and correct thermal simulation of these structures is needed during the design process. The paper presents the (mu) S-THERMANAL thermal simulation tool which is capable to simulate cantilever, bridge etc. microsystem structures both in steady-state and in the frequency-domain case. The algorithms of the program, based on the Fourier method, are detailed in the paper and numerous examples illustrate the capabilities of the tool.

This paper presents techniques and procedures for addressing the three major problems of mechanical testing of the thin films used in surface micromachined microelectromechanical systems--specimen handling, friction, and strain measurement. The polysilicon tensile specimens are fabricated with two supporting side strips on silicon wafers at the Microelectronic Center of North Carolina. The tensile specimen is released by etching away the wafer, and the two support strips are cut after the specimen is glued in the test machine. Friction is reduced by a linear air bearing in the load train, and strain is measured with a noncontacting technique based on laser interferometry between two gold lines on the tensile specimen. The Young's modulus of polysilicon is 170 +/- 7 GPa and the strength is 1.21 +/- 0.16 GPa from a series of 29 tests. preliminary measurements have been made of Poisson's ratio and the fatigue behavior, and an attempt is underway to measure the fracture toughness.

This paper proposes the new technique for the frequency response characterization of the laser vibrometry or the laser displacementmetry, where the optical interference is the working principle. In order to investigate the frequency response of laser vibrometers or laser displacement meters, the surface of high speed translational motion with the broad frequency bandwidth is absolutely required. That motion is materialized by the reflection of an elastic pulse propagating in a metal bar. A projectile made of aluminum is accelerated by the pressurized air and impinges on one end surface of the bar. The elastic wave is generated by the collision and propagates in the bar axis direction and reflects at the other end surface of the bar. The bar is supported by four steel bearing balls which are placed on the V-shaped grooves. The motion of the end surface can be considered to be in plain based on the numerical calculation. The surface is measured simultaneously using the reference laser interferometer developed in NRLM and a laser displacement meter based on the heterodyne technique (Hoshin Electronics HS-1100). HS-1100 uses the real time fringe counting technique. The reference interferometer, on the other hand uses a transient recorder (Tektronix RTD-710) which stores all of the interference signals during the elastic pulse reflection. The analysis and the wave form calculation based on the phase analysis is done after the experiment, leading to the broad frequency bandwidth. The comparison in the frequency domain using Fast Fourier Transform provides the frequency response characteristics of the tested laser displacement meter. It turned out that bandwidth of HS-1100 was up to 20 kHz, though the design value was 100 kHz.

This research was performed to address the issue of shock robustness in silicon microstructures. The improvements were incorporated by considering features to reduce stress concentration and by geometries that have a more uniform stress distribution. The design were evaluated by finite element models and by testing with wafer level techniques. The designs were intended to have the same fundamental frequency, inertia properties and damping properties. Six different designs were developed and distributed across 900 die on multiple 4-inch wafers. The wafers were subjected to repeated shocks at magnitudes of 130, 2008, and 3680 gs with a 0.25 msec duration. Automated optical inspection was used to interrogate each die and determine which test structures survived the shock test. Subsequent to testing, analysis of variance was used to identify the significant factors that influence the failure rate. This analysis has shown beam design, wafer orientation, acceleration level, and the interactions of beam design*wafer orientation, wafer orientation*acceleration level to be significant factors contributing to the failure rate. The designs were grouped according to mean failure rate. The `small bow tie' design had the highest failure rate and was a separate population. Its failure rate was two to four times that of other designs. The second grouping of lower failure rates included all designs to address the stress concentration. Of these designs, the `no gusset' design has the highest failure rate (twice that of other designs). The final grouping includes the gusset designs and the `medium' and `large bow tie' designs. The designs to improve stress distribution had the lowest mean failure rates of all designs.

A characterization method based on beam-bending experiments and finite element simulations has been developed. Calibrated microweights are applied to double-beam test devices with typical beam widths of 100 micrometers and lengths of 2 mm to determine load-dependent displacements with a maximum resolution of about 2 (mu) N and 2 micrometers , respectively. The resulting characteristics are used to determine the corresponding stress-strain characteristics, transformation temperatures and stress-rates of the material. The method has been used to study test devices of TiNi thin sheets with thicknesses d between 160 and 20 micrometers and of sputtered thin films (d equals 8 micrometers ) microfabricated by laser cutting or electrolytic photoetching. The measurements did not show any influence of the microfabrication processes. An investigation of size effects in test devices with decreasing thicknesses revealed enhanced transformation hystereses for thicknesses in the order of the grain size.

The mass production of silicon accelerometers has clarified that the current acceleration standard is not perfect. The acceleration standard is usually transferred by a reference accelerometer with the so-called back-to-back connection technique. Manufacturers, however do not explain what sort of calibration technique is applied to the reference accelerometer in the impact acceleration range. This paper proposes a novel impact technique for accelerometers calibration. The input acceleration to an accelerometer to be tested is generated by the reflection of an elastic pulse at one end surface of a bar. The bar is called Davies Bar, after Prof. Davies, who measured the dynamic displacement of the end surface of a metal bar by electrodes. The experiment was the comparison between the calibration of RION PV-44A accelerometer by ENDEVCO 2270 and that by NRLM method. The paper concludes that Davies' Bar should be used as the reference for the impact acceleration, ranging from roughly 200 [m/s²] to 1000,000 [m/s²] for mainly following reasons: (1) NRLM method is based on laser interferometer measurement with the reliable accuracy. (2) The frequency bandwidth of the impact acceleration generated using Davies bar is much wider than that of reference accelerometers. (3) Back to back connection does not always enable the comparison between the measurement of the connecting surface motion and the accelerometers' outputs.

An important aspect for the development of micromanufactured components and systems is to reduce the time and cost required to reach the prototype stage. At present, this development typically spans several years. Any fabrication approach which would reduce the cost and time-to-prototype would allow for the more rapid development of design concepts and the more rapid evolution of the design cycle. Direct fabrication of masks for X-ray lithography, by mechanical micromilling, is one potential avenue for rapid, lower cost development. The key process requirements for the fabrication of a typical X-ray mask involves the selection of both substrate and absorber materials. The substrate must provide a mechanically stable support for the patterned absorber without introducing excessive attenuation of the X- ray flux that ultimately reaches the resist surface. Frame supported, thin membranes (such as SiC, C, Si₃N₄, Si) are most often used as well as low atomic number bulk materials (Be). The choice of elemental composition and thickness for the absorber will be largely determined by the resist sensitivity and the X-ray wavelength used. Many process steps are required in order to define the final absorber pattern geometry and will generally involve either additive or subtractive processes. Mechanical micromilling techniques may be used with either a single bulk material which serves the dual role of both substrate and absorber or with a composite structure consisting of a thin gold layer deposited on a thick, low atomic number bulk substrate. Single material masks of aluminum and graphite have been investigated. A composite mask of graphite with a thin layer of sputtered gold has also been investigated. The paper will report on the developmental work for both types of masks and will give results for synchrotron X-ray exposure using these masks. Problems associated with using micromilling as an X- ray mask fabrication method will also be presented.

The National Institute of Standards and Technology is developing a dimensional pitch standard covering the range 1 micrometers to 10 mm, intended for the calibration of microscope magnification and of dimensional metrology instrument scales. Called SRM 2800, Microscope Magnification Standard, it consists of symmetrical nested linear pitch patterns in decade ranges printed in one direction on a quartz microscope slide. The array of parallel lines is printed on a clear background to facilitate use in optical microscopes using transmission mode or reflection mode illumination. This pitch standard is also useful in atomic force microscopes, and in scanning electron microscopes and scanning tunneling microscopes when coated with a conducting film (although there are other standards from NIST which are more suitable for SEMs). It can be used to calibrate the scales of micromachining tools. The positions of the centers of the lines relative to the origin in the center of the pattern will be certified. The linewidths are not calibrated. While this standard facilitates accurate magnification and scale calibration, care must be taken when measuring the size (left edge to right edge, or linewidth) of an object. The appropriate definition for `edge' becomes an important issue, and proximity effects and edge effects can become important when the required measurement uncertainty is less than the wavelength of the light used.

Electrical critical dimension (ECD) test structures have been adapted for use in a surface micromachining environment and fabricated along side various MicroElectroMechanical Systems (MEMS) structures. These freestanding ECD test structures, which are exposed to air on all surfaces (that is, no encompassing oxide), provide the ability to measure two key metrological process parameters, sheet resistance and feature width, that can affect the threshold at which released fixed-fixed beam MEMS structures experience deflection due to residual compressive strain.

The X-ray lithography and micromachining facility at CAMD hosts the `print-shop' for the development and prototype exposures in LIGA-like processing techniques for the HI-MEMS Alliance. A simple fixture with alignment, tilt, and rotation modules has been developed. It allows for multiple level exposures with registration. More complex shapes can be achieved by rotating and tilting the mask/wafer assembly with respect to the incident X-ray beam. The alignment system is based on optical registration using an X-ray mask with targets on optically transparent windows. The masks were fabricated at MCNC. The alignment tests and off-axis exposures were performed at CAMD. Overlay accuracy of +/- 5 micrometers has been demonstrated.

The Advanced Photon Source (APS) is a third-generation synchrotron radiation source. With a characteristic x-ray energy of 19.5 keV and highly collimated beam (< 0.1 mrad), the APS is well suited for producing high-aspect- ratio microstructures in thick resist films (> 1 mm) using deep x-ray lithography (DXRL). The 2-BM beamline has been constructed and will be used for DXRL at the APS. Selection of the appropriate x-ray energy range is accomplished by a variable-angle mirror and various filters installed in the beamline. At the exposure station, the beam size will be 100 (H) X 5 (V) mm². Uniform exposure will be achieved by a high-speed (100 mm/sec) vertical scanner. The scanner allows precise angular (approximately 0.1 mrad) and positional (< 1 micrometers ) control of the sample, allowing full use of the highly collimated beam for lateral accuracy and control of sidewall slopes during exposure of thick resists, as well as the generation of conicals and other profiles. For 1-mm thick PMMA, a 100 X 25 mm² area can be fully exposed in about 1/2 hour, while even 10-mm thick PMMA will require only 2 - 3 hours.

The MicroSystems Engineering Team ((mu) SET) at Louisiana State University, in close collaboration with the Center for Advanced Microstructures and Devices, has successfully completed the lithography and electroplating steps of the LIGA process sequence using cyanoacrylate to bond a PMMA resist layer to a nickel surface. Nickel microstructures 300 micrometers in height have been electroplated. Tests were performed which indicate that the bond between cyanoacrylate and nickel is much stronger than the bond between PMMA and nickel.

Temperature measurements of thick PMMA resist during X-ray (1 to 5 keV) exposure are presented in this paper. Thin metal (gold) film thermal sensors were fabricated directly on the resist surface and on the resist/substrate interface using micro-lithography methods. The temperature measurements were conducted in vacuum (< 10^-4 Torr) and in 1 to 25 Torr helium pressure--conditions corresponding to typically X-ray lithography exposure. The results of temperature rise measurements performed with thermal sensors and with miniature conventional thermocouples are compared.

A LIGA based tool-set of tips for various scanning probe applications is under investigation by the LSU (mu) SET. This involves fabrication of `micro-columns' using LIGA, followed by an electrochemical sharpening process. Micro-columns ranging from 1.8 micrometers diameter and 14 micrometers tall to 165 micrometers X 165 micrometers and 1000 micrometers tall have been fabricated. In order to understand the sharpening mechanism, commercially available wires with diameters ranging from 25 - 800 micrometers were sharpened. A computer aided design tool, based on deforming finite elements, was developed to simulate the sharpening process.

We have measured the dimensional variation and sidewall roughness of features on PMMA microcomponents fabricated by deep x-ray lithography in order to assess the effect of dimensional variation on subsequent assembly operations. Dimensional measurements were made using a stylus profilometer with a repeatability in step height of better than 0.01 micrometers . Roughness measurements were made with the same profilometer scanning in a direction perpendicular to the length of the parts. 22 micrometers and 54 micrometers features exhibited dimensional variations described by a Gaussian distribution with standard deviations of 0.202 micrometers and 0.381 micrometers , respectively. This corresponds to a maximum relative variation of between 0.6% and 0.9%. Sidewall roughnesses were found to be in the range of 0.02 micrometers to 0.03 micrometers , an insignificant contribution to the total variation when compared to overall dimensional variation. Several potential sources of this variation are discussed, but no single cause was identified as the source of the significant dimensional variation observed here.

We report the technology for the design, fabrication and testing of polysilicon microheaters in silicon using a standard 2 micrometers n-well CMOS technology. The polysilicon microheaters are realized in two steps: layout design for CMOS process and post processing etching. An additional layer in CMOS technology called `open' was incorporated. The `open' layer creates a direct opening to the substrate. Post processing is done on the fabricated CMOS chips using isotropic etchant like xenon difluoride (XeF₂) or anisotropic etchant like ethylenediamine pyrocatechol (EDP) to create a `cavity' in the silicon substrate. The cavity provides thermal isolation from the polysilicon microheaters to the circuits and other devices. These microheaters can reach incandescence at very low power. Several test devices incorporating arrays of polysilicon microheaters were designed and fabricated. Measurements are presented that verify the design and performance of the microheater.

This paper presents a novel technique for fabricating 3D patterns in a thick layered resist and describes an alignment aide designed for the specific application of thick resist x-ray micromachining. In this technique, a PMMA layer of desired thickness is formed on a substrate by spinning or solvent bonding. The layer is exposed with X- rays to generate a latent image. A second layer of PMMA is bonded over the first layer and is exposed with an appropriate mask, generating a latent image in the second layer. This process can be repeated several times creating a 3D latent image. Simultaneous development forms a true 3D pattern in the PMMA resist.

Besides foundry facilities, Computer-Aided Design (CAD) tools are also required to move microsystems from research prototypes to an industrial market. This paper describes a Computer-Aided-Design Framework for microsystems, based on selected existing software packages adapted and extended for microsystem technology, assembled with libraries where models are available in the form of standard cells described at different levels (symbolic, system/behavioral, layout). In microelectronics, CAD has already attained a highly sophisticated and professional level, where complete fabrication sequences are simulated and the device and system operation is completely tested before manufacturing. In comparison, the art of microsystem design and modelling is still in its infancy. However, at least for the numerical simulation of the operation of single microsystem components, such as mechanical resonators, thermo-elements, elastic diaphragms, reliable simulation tools are available. For the different engineering disciplines (like electronics, mechanics, optics, etc) a lot of CAD-tools for the design, simulation and verification of specific devices are available, but there is no CAD-environment within which we could perform a (micro-)system simulation due to the different nature of the devices. In general there are two different approaches to overcome this limitation: the first possibility would be to develop a new framework tailored for microsystem-engineering. The second approach, much more realistic, would be to use the existing CAD-tools which contain the most promising features, and to extend these tools so that they can be used for the simulation and verification of microsystems and of the devices involved. These tools are assembled with libraries in a microsystem design environment allowing a continuous design flow. The approach is driven by the wish to make microsystems accessible to a large community of people, including SMEs and non-specialized academic institutions.

The use of non-focused and focused ion beams as tools for fabrication and assembly of microstructures is described. Non-focused, low energy (< 1.5 keV) and high current density (< 100 mA cm^-2) argon ion beams produced by a Kaufman-type source have been used for ultra-precision micromachining of materials for microelectromechanical systems applications. Uniform material removal rates of up to 1 micrometers min^-1 without reactive etching are achieved during stencil-mask milling of micro-parts or during pattern transfer into ceramic or semiconductor substrates by photolithography followed by ion milling. Micro-components with typical dimensions in the 1 - 100 micrometers range and having dimensional tolerances of order 0.1 micrometers have been demonstrated, consisting of ultra-thin plates, beams, shafts and cantilevers. Self supporting nickel, aluminium, stainless steel and mu-metal plates with thicknesses down to 1 micrometers have then been used for fabricating more complex micro-parts such as disks, gears and cogs by direct writing using focused ion beam (FIB) micromachining with a resolution of 50 nm. The FIB instrument allows in situ imaging during microfabrication using secondary elements or ions, and can be used for inspection during micro-part assembly. A novel process applicable to the production of 3D micro-parts is also described.

Atomic Force Microscope (AFM) is a very versatile instrument enabling precise surface investigations. The sensitivity of the AFM depends on the parameters of the detector system, which is used to observe the beam motions. In our experiments we have used a cantilever with integrated Wheatstone piezoresistive bridge as a deflection sensor. In this case of nonhomogeneous surfaces not only topography measurements but also investigations of other surface properties in nanometer scale are very important. In this paper we will describe the Lateral Force Microscope utilizing the Wheatstone bridge piezoresistive cantilever. During topography measurements of the nonhomogeneous smooth samples in contact mode the lateral/friction forces change depending on the on the substrate material differences. Thus friction forces imaging enables an investigation of the surface material structure. Measurement setup of the lateral force microscope with Wheatstone bridge piezoresistive cantilever will be presented. Noise considerations of the described lateral forces measurements method with Wheatstone bridge cantilever will be discussed. Measures for improving of the friction force observations will be proposed. We will show results of the topography and friction force measurements on chromium/quartz mask structure.

Atomic Force Microscopy (AFM) is a very sensitive technique to determine the surface topography. Recent developments enable investigations of other microtribological sample properties like elasticity, friction coefficients of the material, which is present on the observed surface. Although, measurements of small cantilever displacements are required in all AFM techniques. In our experiments we have used a cantilever with integrated Wheatstone piezoresistive bridge as a deflection sensor. This cantilever displacement detection system enables the investigations in UHV and low temperature conditions. In this paper we will analyze the sensitivity of the force observations with the piezoresistive Wheatstone bridge cantilever. We will examine how the detector response depends on the beam geometry. Noise considerations of the beam motion measurements method will be discussed. We will present the noise properties of the Wheatstone bridge piezoresistive detector and cantilever system. Measures for improving of the force measurements sensitivity will be proposed.

Mechanical properties of titanium thin films of 0.5 micrometers thickness and aluminum thin films of 1.0 micrometers thickness, microfabricated by magnetron spattering, were measured by using a novel tensile machine. These thin films are extremely difficult to handle because they are very fragile, so the thin film specimens were fabricated by using semiconductor manufacturing technology in a silicon frame to protect them. The test section of these specimens was 300 micrometers in width and 1400 micrometers in gauge length. By gripping the thin film specimen with a new device using a micrometer, it could be mounted on the tensile machine easily. The stress-train diagrams of both thin films were measured continuously from elastic deformation to plastic deformation in the atmosphere at room temperature. The experimental results indicated that the titanium thin film and the aluminum thin film had a smaller breaking elongation although they had a larger tensile strength than bulk pure titanium and bulk pure aluminum, respectively.

We investigate the transient thermal response of micromachined silicon microbridges. The silicon microbridge has a large potential for sensors relating to heat because silicon has large thermal conductivity. The silicon microbridge is stable in heat cycle compared with the other hetero-structures. The silicon process has an advantage of mass production and good controllability. The silicon microbridge is abruptly heated by its Joule's heat when a voltage pulse is applied. The measured time constant was less than 1 ms because the heat capacity of the microbridge is small. A heavily doped silicon layer which is made by ion implantation works as stopping layer for anisotropic etching process. Furthermore the dependence of resistance on temperature is metallic such that the drive current is automatically controlled with negative feedback. We could easily control the temperature of silicon microbridge by electric signal up to the frequency range of 1 kHz. The temperature modulation was more than 700 degree(s)C at 100 Hz. The microbridge is one of the fastest heater driven by Joule's heat because of the small heat capacity and the large thermal conductivity of silicon.

The possibility of fabricating mm-wave radio frequency cavities using deep x-ray lithography (DXRL) is being investigated. The frequency of operation can be from 30 GHz to 300 GHz, operating mode in either TM or TE-mode, depending on the application. For most applications, a complete structure consists of two mirror-image planar half structures assembled face-to-face. The fabrication process includes manufacture of precision x-ray masks, exposure of positive resist by x-rays through the mask, resist development, and electroforming of the final microstructure. The precision hard x-ray mask was made by means of an surface mask, using soft x-ray lithography for pattern transfer into poly-methylmethacrylate (PMMA) on a 200-micrometers thick Si wafer, followed by electroplating of 35-micrometers Au at CXrL (Center of X-ray Lithography) in Wisconsin. For the DXRL process, PMMA was used as the positive resist, either as an 1-mm sheet glued or 200-micrometers film cast onto a Cu substrate. The NSLS (National Synchrotron Light Source) X- 26C beamline in Brookhaven was used to expose the resist. 99.9% OFC (oxygen free copper) was electroplated onto the developed PMMA structure, and then polished by the diamond- lapping. The cavity will be aligned with the optical fibers on the grooves and then initial test will be performed with HP 8510 network analyzer.

A new optical system has recently been designed, built, and tested to meet the demands of large area lithography applications. The new optical system is referred to as Scanning Array Lens LithographY (SALLY) and is based on the well-known Wynne Dyson 1:1 projection lens configuration that has found widespread use in the IC, thin-film head, and micromachining industries. Recent advances in the areas of optical design, alignment, assembly and packaging have led to the development of an array lens that essentially projects a single elongated field that can be extended to span the width of any substrate. This enables a substrate to be exposed in a single scanning motion. The array lens is composed of multiple compact, catadioptric lens relays having trapezoidal shaped image fields that are positioned in an alternating and overlapping fashion. The resulting imaging capability is indistinguishable from that which would be accomplished by a single very large, well-corrected lens. Features exposed in the transition between separate fields exhibit no visible variations in their structures. This paper describes a three field prototype SALLY system composed of lens relays with a numerical aperture (NA) of 0.10 designed to include the g- and h-lines of the mercury spectrum. This NA was selected to provide a useful combination of resolution, depth-of-focus, and exposure irradiance for a range of applications including micromachining. Test results demonstrate a seamless transition between separate image fields and resolution of equal line/space patterns down to 2.3 micrometers . Thick resist film imagery showing thickness to linewidth aspect ratios of up to 4:1 using conventional application and development techniques are also shown.

Micromachine technologies based on IC-compatible micromachining have advantages denoted by three "M's'. Miniaturization is the most popular but Multiplicity, which means the batch fabrication capability of many complicated elements, and Microelectronics to control motions or to add different functions such as the optical function are equally important. This paper deals with the application of micromachine technologies to micro optical devices. A basic concept making the best use of the advantages is proposed. Recent examples of optical microelectromechanical systems(MEMS) are reviewed.

MEMS as a technology base is coming of age, but as in any vital process growing pains occur. Commercializing MEMS is simultaneously viewed as agonizingly slow by many of its promoters and lightingly quick by many companies whose products are being replaced with MEMS based substitutes. This effort ties current efforts in market analysis, technology evaluations, competency based strategy in an effort to understand the pace of MEMS commercialization.