(Hetrojunction Bipolar Transistors) technologies are used
in Micro Mobio's integrated power amplifiers. It is a bipolar
transistor constructed with a hetrojunction made of such as
InGaP/GaAs or SiGe at the junctions. This bandgap engineering
creates a potential barrier, which allows heavy doping concentration
without sacrificing the current gain, increasing the power
gain and switching speed of the device.