This paper summarizes very recent developments in the MEMS application of a novel material-class, manufactured by new processing methods. This technology has two unique aspects: (1) The materials form a continuum from high temperature polymers to ultrahigh temperature ceramics. We call them polymer-derived-ceramics (PDCs). In addition to being mechanically robust and chemically inert, the PDCs can be functionalized to embody electronic, optical and magnetic properties. (2) PDC-MEMS are processed from liquid precursors by a simple UV photolithographic photo-curing process. Multilayer structures can be made by stereo lithography or by simple bonding of the polymer structures. The PDC-MEMS technology will be demonstrated by two examples: an optical grating made from the transparent polymer version of the PDC, and a microigniter operating at 1300-1500°C made from the ceramic version. A special feature of the Colorado work is the development of a real-time human-machine-interface (HMI) along-side the design and testing of the MEMS devices. For example, a live HMI for the microigniter gives information such as tip temperature, remaining life and damage accumulation. Finally, the PDC-MEMS technology is inexpensive.
Diamond particles were employed to toughen zinc sulfide--an infrared transparent, but mechanically weak material in its pure state. The optical properties of pure ZnS were preserved in a composite when the diamond particles were well dispersed and, when compared to the wavelength, their sizes were sufficiently small. Careful control of the processing parameters was required to maintain a small grain size and to limit the phase transformation of ZnS to a non-cubic phase at high temperatures. Measurement of the reflectivity of this composite in the region of the lattice vibration spectrum was used to compare the measured electrodynamic properties with those predicted by two different theoretical models that assume different microstructural morphology. Good agreement was found with the Bruggemann model that assumes both components in the composite have the same type of interconnectedness.