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Virtually every academic department in an institute of higher education requires Web presence as a critical component of its information technology strategy. The problem of how to leverage the World Wide Web and build effective and useful departmental Web sites seems to have long been solved. Yet browsing academic Web sites from around the world reveals a range from a mere collection of static HTML pages to more sophisticated enterprise-strength portals. If one pauses to think about current practices and the issues an academic department faces, and then measures these against an "ideal" set of features a next-generation academic site should have, one will find an open-ended, complex problem rather than a "solved" one. In this article, the authors provide a roadmap, based on their experiences, for developing a cost-effective and successful academic Web site. They believe that their experience and strategy can help an academic department build an innovative Web presence and provide critical IT support for its research and educational missions. (Contains 5 endnotes.)

A study is conducted to determine the Young's modulus, residual stress, and burst strength of polycrystalline 3C silicon carbide (poly-SiC) films grown on as-deposited and annealed polysilicon substrate layers. Results reveal that poly Si-C films have Young's modulus values ranging from 452-494GPa while films with a high degree of (110) texture exhibited Young's modulus values from 340 to 357 GPa.

Microscale tensile specimens of epitaxial 3C silicon carbide (3C-SiC) thin films were fabricated on Si substrates and tested to provide measurements of strength and elastic modulus. Samples were fabricated using both micromolding and reactive ion etching (RIE) processes to pattern the 3C-SiC films. All specimens were on the (100) plane with a (110) tensile direction. Testing was performed on a microsample tensile testing machine previously used on other materials. The samples had a thickness of 0.5 to 2 [micro]m, a gauge length of 4 mm, and a minimum width of 600 [micro]m. Testing results show an average strength of 1.19 [+ or -] 0.53 GPa and 1.65 =t= 0.39 GPa for micromolded and RIE patterned specimens, respectively. The elastic modulus was measured to be 424 [+ or -] 44 GPa, which was consistent with but slightly lower than the elastic modulus calculated with single crystal elastic constants found by ab initio calculations. [1342] Index Terms--3C silicon carbide (3C-SiC), mechanical properties, microfabrication, tensile testing.

This manuscript is the first of a two-part series describing the fabrication and testing of MHz frequency, polycrystalline silicon-carbide (poly-SiC) micromechanical resonators made from films deposited by atmospheric-pressure chemical-vapor deposition (APCVD). In Part I, the development of deposition and patterning techniques suitable for the fabrication of vertically actuated, clamped-clamped beam resonant structures is detailed. Recipe development involved film deposition and material analysis on both planar and patterned substrates. We found that a carbonization-based deposition process modeled after epitaxial growth of 3C-SiC on Si produced the highest quality poly-SiC films for use with sub-micron thick polysilicon sacrificial layers, regardless of topology. Devices utilizing beam thicknesses up to 1 [micro]m were fabricated and successfully released. Details about the testing of the released structures are presented in Part 2 of this series (see Wiser, Tabib-Azar, Mehregan, and Zorman, 'Polycrystailine silicon-carbide surface-micromachined vertical resonators--Part II: Electrical testing and material property extraction,' J. Microelectromech. Syst., vol. 14, no. 3, Jun. 2005). [1029]

This manuscript is the second of a two part series describing the fabrication and testing of megahertz frequency, polycrystalline silicon-carbide (poly-SiC) micromechanical resonators made from films deposited by atmospheric pressure chemical vapor deposition. In Part I, the development of deposition and patterning techniques suitable for the fabrication of vertically actuated, clamped-clamped beam resonant structures was detailed (see Wiser, Chung, Mehregan, and Zorman, 'Polycrystalline Silicon-Carbide Surface-Micromachined Vertical Resonators--Part I: Growth Study and Device Fabrication,' J. Microelectromech. Syst., vol. 14, no. 3, Jun. 2005). This paper describes the testing procedures used to determine the nominal resonant frequencies and quality factors for these resonators, as well as the methods used to calculate the Young's modulus and residual stress of the poly-SiC films from the resonant frequency data. Poly-SiC devices with a resonant frequency ranging from 1 to 4 MHz and quality factors of around 2500 were successfully tested. The quality factors were lower than expected for devices of this design. Modeling and experimental results indicate that the low values are likely due to insufficient doping in the poly-SiC films. Both the Young's modulus and residual stress values calculated for the poly-SiC films (436 GPa and 121 MPa, respectively) compare favorably with values reported in the literature. [1030]

Despite great advancements in thin-film growth and deposition techniques, determination of the residual stress and Young's modulus for thin films has continued to be a challenge. The bulge test is a potentially powerful tool for characterizing these mechanical properties but is underutilized because of its sensitivity to experimental error. The bulge test is highly sensitive to sample and test preparation, accuracy of the deflection measurement, accuracy in the measurement of film dimensions, and selection of the correct equation to be used for extraction of the Young's modulus and residual stress. In this study, effort has been made to consolidate the findings from various reports in the literature, and a thorough error analysis has been conducted. A discussion on the experimental technique used to extract Poisson's ratio from the bulge test is also presented. Finally, the technique is used to determine the residual stress and Young's modulus of 3C-SiC thin films grown on silicon. DOI: 10.1061/(ASCE)0893-1321(2003)16:2(46) CE Database subject headings: Young's modulus; Residual stress; Poisson ratio; Micromechanics.

The development of polycrystalline 3C silicon carbide (polySiC) lateral resonant devices is described. Ceramic-based materials and nickel wirebonding procedures are used for the packaging of polySiC resonators for operation in high temperature environments.

As an alternative to conventional SiC reactive ion etching (RIE), polycrystalline (poly-SiC) films were patterned into micron-sized structures using sacrificial Si[O.sub.2] and polycrystalline silicon (polysilicon) molds in conjunction with mechanical polishing. The molds were made from thermally grown Si[O.sub.2] and LPCVD polysilicon films and were fabricated using conventional patterning techniques. The poly-SiC micromolding process combines film deposition, polishing, and selective wet chemical etching of the molds to achieve the desired pattern. The process is simple and does not suffer from the difficulties associated with RIE of SiC. Micrometer-sized lines, spaces, and complex device structures have been patterned using this technique. The micromolding technique has been used in a SiC surface micromachining process to fabricate fully released lateral resonant structures. Index Terms - Harsh environments, microactuators, microlding, polishing, SiC MEMS.

This paper explores the use of thick glass films as suitable alternatives to CVD oxide films for use as sacrificial, planarization, and passivation layers in polysilicon surface micromachining processes. Such glasses can be spin-coated to produce films up to 20 [[micro]meter] thick in one step and to globally planarize the wafer surface, extending the overall mechanical design capability by enabling additional device structural complexity. Glass optical constants were determined, and the film quality was evaluated using SEM, EDS, XPS, and XRD. The films were found to have low intrinsic stresses and other characteristics desirable for sacrificial layer applications. A glass chemical-mechanical polishing process with 5300-[Angstrom]/min removal rate and acceptable selectivity to polysilicon was developed, along with a wet etch chemistry that preferentially etches the film at 3.24 [[micro]meter]/min without affecting the silicon substrate or the structural polysilicon. The film was used to planarize up to 10-[[micro]meter]-tall topographies associated with surface micromachined features through spin-on and polish-back steps, and was in addition demonstrated to be a viable protective layer for silicon wafers during extended KOH etching in silicon bulk micromachining processes. The glass has stable constituents that do not diffuse or contaminate either the substrate or the device features during the application and firing procedures. Index Terms - Chemical-mechanical polishing (CMP), glass, microactuators, planarization, surface micromachining, thick films.

A study was conducted to evaluate three designs of surface-micromachined shear stress sensors. The designs were calibrated in a continuum flow channel. The first generation of the sensors was fabricated using electrical contact pads. The sensors, which were released supercritically, did not support stiction. Experimental results indicated that the sensors responded linearly to shear force as designed.

A study was conducted to analyze the design and manufacture of shear stress sensors based on the floating-element technique and polysilicon-surface-micromachining technology. Three different designs were developed. The designs support different floating-element geometry and sensor output. Heavily phosphorus-doped polysilicon was then utilized as the structural material for the sensor. In addition, a folded-beam design was used to relieve residual stress in the deposited polysilicon layer.