GaAs HBT profile optimization using the Taguchi method

A method is presented for quantitatively optimizing HBT performance using a combination of physical and equivalent circuit models in the design-of-experiments framework. An optimized profile was designed which demonstrated over 4 dB improvement in Gmax at 10 GHz (over the M/A-COM baseline process) without resorting to reduced device dimensions and/or a thin base layer.