MICROFABRICATED INCANDESCENT LAMPS

A silicon filament vacuum sealed incandescent light source has been fabricated using IC technology. The incandescent source consists of a heavily doped p+ polysilicon filament coated with silicon nitride and enclosed in a vacuum sealed (almost-equal-to 80-mT) cavity in the silicon chip surface. The filament is electrically heated to reach incandescence at a temperature near 1400 K. The power required to achieve this temperature for a filament 510 X 5 X 1-mu-m3 is 5 mW yielding a total optical power of 250-mu-W with a peak distribution wavelength near 2.5-mu-m. The radiation emitted by this source approximately follows Lambert's cosine law. The energy conversion efficiency is 5%.