A new silicon-on-glass process for integrated sensors

A process is reported for the formation of high-performance thin single-crystal silicon films on glass substrates. The process utilizes the electrostatic bonding of a silicon wafer to glass and subsequent etching of the silicon to form films having thickness controlled from less than 2 mu m to over 20 mu m. The use of Corning 1729 glass substrates yields an excellent thermal expansion match to the silicon film and allows the use of postbond processing temperatures for the films of as high as 800 degrees C, allowing the formation of both MOS and bipolar device structures. Thus, integrated circuitry can be incorporated in dissolved-wafer sensing structures. A variety of related processes are also possible where some or all of the silicon device processing is performed at high temperature before bonding to the glass.<>