Gate to source short on epc8009

Hi, we have a buck converter with epc8009. Many times, we blow up a fet, it is the gate, gate to source measures low impedance. what is the mechanism of the gate short.

Mainly it is important to control the voltage on the gate accurately, as the typical operating voltage is relatively close to the abs max rating.
Since EPC8xxx series are very, very fast FETs a lot of care should be taken…
First thing to check is layout, in particular common source inductance. Next would be the bootstrap voltage. Then try and measure the gate voltage during operation. This is a difficult measurement to make, take a look at this page for recommendations and further reading: Gallium Nitride Measurement Techniques | GaN First Time Right |EPC ( Also make sure to measure as close as possible to the device.