Vacuum-sealed silicon micromachined incandescent light source

A silicon-filament vacuum-sealed incandescent light has been fabricated using technologies and materials derived from IC processes. The incandescent source consists of a heavily doped p/sup +/ polysilicon filament coated with silicon nitride and enclosed in a vacuum-sealed ( approximately=80 mT) cavity. The filament is electrically heated to reach a maximum temperature between 1500 and 1600 K, corresponding to a peak black body wavelength at approximately 2 mu m. The power required to achieve this temperature in a filament 350*3*1 mu m/sup 3/ is 3.5 mW. The cavity is sealed with a silicon-nitride window that is highly transmissive to the emitted radiation. The microlamp can be processed compatibly with circuits and has been operated in a liquid ambient. Without substrate cooling it requires several milliseconds for complete turn-off after being disconnected from power.<>