A 10 MHz–6 GHz high power high linearity 35 dB digital step attenuator MMIC using GaN HEMTs with TaON passivation

This paper describes a 10 MHz–6 GHz high power high linearity 35 dB digital step attenuator monolithic microwave integrated circuit (MMIC) for radio frequency automated test equipment (RF ATE) systems. The digital step attenuator MMIC is fabricated using a novel Schottky gallium nitride high electron mobility transistor (GaN HEMT) process that is characterized in very low gate leakage current with tantalum oxy nitride (TaON) passivation technology. Owing to the characteristic of the developed GaN HEMT, circuit topologies for improving large signal performance in wideband from lower frequency can be employed, and the MMIC shows input 1 dB compression point (IP1dB) of more than +40 dBm and input 3rd order intercept point (IIP3) of more than +55 dBm.