A method for forming a semiconductor device including a GaN FET, an overvoltage clamping component, and a voltage dropping component. The GaN FET is formed by forming a low-defect layer comprising gallium nitride, a barrier layer comprising AlxGa1−xN, a gate, and source and drain contacts. The overvoltage clamping component is coupled to a drain node of the GaN FET. The overvoltage clamping component conducts insignificant current when a voltage at the drain node is less than a safe voltage limit and conducts significant current when the voltage rises above the safe voltage limit. The voltage dropping component is coupled to the overvoltage clamping component and to a terminal for a bias potential. The voltage dropping component provides a voltage drop which increases as current from the overvoltage clamping component increases. The GaN FET turns on when the voltage drop reaches a threshold value.