Alumina Ceramics and Its Applications

Microstructured surfaces, as well as micromachined substrates and devices discussed in Sects. II, III, and iy are suitable for a number of applications. They include reflective and absorbing surfaces, wavelength-sensitive filters, multiaperture lens arrays and Fresnel microoptics, field emitter arrays, precision apertures, or molds for microstructured surfaces of other materials. Microstructured alumina ceramics can also be used for tuned broadband infrared emitters. In addition, due to the robustness at high temperatures and well-developed and controlled porosity, the freestanding, heat-treated micromachined anodic alumina substrates can be used for the fabrication of sensors that incorporate a high temperature microheater with low power consumption. 

EMM can be applied to either Al films, typically deposited on SiCVSi substrates, or Al foils. The dimensions of metallic features are determined by the same rules the etch factor, the depth of porous-type anodization, the mask design, and process conditions. In addition to the fabrication of metallic microstructures, EMM can be used to produce microstructured ceramic substrates composed of porous AI2O3. For the fabrication of both types of 3D microstructures by localized porous-type anodization, the following technological problems have to be addressed the reliability of a mask material, the fidelity of the mask transfer, volumetric expansion of porous AI2O3 during anodization, and the effect of the mask design on the rate of porous-type anodization and on the completion of anodization of the entire thickness of Al without traces of Al islands. 

Mardilovich, A. N. Govyadinov, V V Kozharinov, and R. Paterson, in Advances in Science and Technology. Ceramics Charting the Future, Ed. by P. Vincenzini, Techna, Florence, Italy (1995) 2763. 

Mardilovich, D. Routkevitch, and A. Govyadinov, in Microfabricated Systems and MEMS V, Proceedings by Electrochemical Society, 2000-19, Ed. P. J. Hesketh et al. (2000) 33. 

Routkevitch, A. Govyadinov, and P. Mardilovich, in Proceedings of the ASME International Mechanical Engineering Congress and Exposition, Nov. 5-10, 2000, Orlando, Florida, Vol. 2, ASME, New York (2000) 39. 

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