Thin films of silicon nitride and silicon dioxide protect the thin-film platinum resistive heater from the environment. The silicon nitride also offers thermal and electrical isolation.
The device is 1 1 0.38 mm. It is micromachined to accommodate the 0.25 0.25-mm platinum element. Electrical inputs up to 25 mA, 4,600 mV, and 115 mW heat the element. The die is mounted in a goldplated TO-18 package with gold ball wire bonding.
Irvine, CA 92616