Patent ID: 7317234

Claim:
An electronic circuit comprised of: a capacitor having a first electrode formed using a conductive layer of a silicon integrated circuit and a second electrode formed from a flexible conductive metallic foil, solder bumps technology on the integrated circuit wafer used to fabricate said silicon integrated circuit, said second electrode attached to said solder bumps, said foil during assembly being held firmly by means of a hot vacuum chuck and said solder bumped wafer pressed against it so that all the integrated circuits on said wafer receive said microphone circuit at the same time, said foil then attached to said solder bumps by solder reflow via heating through the means used to hold the foil, said foil on each integrated circuit separated from the rest of the foil by means of laser scribing after said attachment is made, any residual said foil being easily blow away from the wafer by any low pressure air flow, a charge stored on said capacitor, whereby sound energy striking said second electrode deflects said second electrode causing a change in the value of said capacitor causing a change in charge which is signal current.