Patent ID: 7487675

Claim:
A micro-heater comprising: a semiconductor substrate having a cavity; an insulating layer provided on an upper surface of said semiconductor substrate and closing said cavity; and a heater element embedded in a portion of said insulating layer above the cavity, wherein said insulating layer includes: a first tensile stress film provided on said semiconductor substrate; a first compressive stress film provided on said first tensile stress film; a second compressive stress film provided on said first compressive stress film; and a second tensile stress film provided on said second compressive stress film, wherein each of said compressive stress films comprises silicon oxide, said first tensile stress film comprises silicon nitride and has a thickness not less than that of said first compressive stress film, said second tensile stress film comprises silicon nitride and has a thickness not less than that of said second compressive stress film, and said heater element is interposed between said first and second compressive stress films above the cavity so that it is embedded in said insulating layer.