Micromachined thermal radiation emitter from a commercial CMOS process

Fabrication of thermally isolated micromechanical structures capable of generating thermal radiation for dynamic thermal scene simulation (DTSS) is described. Complete compatibility with a commercial CMOS process is achieved through design of a novel, but acceptable, layout for implementation by the CMOS foundry using its regular process sequence. Following commercial production and delivery of the CMOS chips, a single maskless etch in an aqueous ethylemediamine-pyrocatechol mixture is performed to realize the micromechanical structures. The resulting structures are suspended plates consisting of polysilicon resistors encapsulated in the field and CVD (chemical-vapor-deposited) oxides available in the CMOS process. The plates are suspended by aluminum heater leads that are also encapsulated in the field and CVD oxides. Studies of the suitability of these structures for DTSS have been initiated, and early favorable results are reported.<>