Your threshold voltage is low compared with silicon MOSFETs. How does this impact turn off speed?
eGaN devices have a very low temperature coefficient for their threshold voltage. This gives the user added safety margin despite the lower threshold voltages at room temperature. The Miller Capacitance, CGD of EPC eGaN devices is also very low, hence the switching speed is quite high; it can be turned off in a few nano seconds. In order to avoid dv/dt turn-on, it is critical to have very low impedance in the gate-source circuit as well as a low impedance pull down for the gate circuit. There are available gate drivers designed specifically for eGaN devices that will take care of many of these requirements. A list of GaN compatible drivers and controllers can be found on the eGaN Drivers and Controllers page. For more tips on driving eGaN FETs, see eGaN FET Drivers and Layout Considerations.