Technologies for MMICs at microwave frequencies

The development of process technologies for microwave and millimetre wave integrated circuits poses a number of wide ranging challenges for the process engineer. The diversity of frequencies from about 1 GHz to 100 GHz means that a standard technology cannot be adopted for the whole frequency spectrum as the circuit topology required at each end of this frequency range differ widely. At low frequencies, ~1 GHz, traditional distributed (microstrip) style matching elements consume too much surface area of GaAs and so RF techniques using lumped inductors, capacitors and resistors are used. It is only at frequencies in excess of 6-7 GHz that fully distributed circuits are small enough to enable utilisation of this type of impedance matching