The device reliability problems of the bonding wire array in gallium nitride (GaN)-based high electron mobility transistor (HEMT) power amplifier become more and more serious due to high-voltage operation, impedance mismatching conditions, and so on. In this paper, both the experimental and theoretical studies on the electrothermal responses of bonding wire arrays in GaN power amplifier are performed. By using the finite element method to self-consistently solve the current transport and heat conduction equations, the temperature distributions of the GaN die surface and the bonding wire array under the continuous wave input signals of different power can be obtained, which are consistent with the experimental results captured by the IR microscopy of the measurement system.
