EPC GaN HEMT - why is reverse conduction threshold different

Characteristics of GaN FETs and ICs
1

For reverse conduction in GaN, the same 2DEG is used that is used in forward conduction.
So, why is the reverse conduction threshold voltage (Vsd) for a certain current different to the forward conduction threshold voltage for the same current?

2

hello,
the reverse conduction when the gate is ON is identical to the forward conduction. When the gate is OFF the mechanism is different: you can look at an explanation here
Why do eGaN FETs conduct in the reverse (S-D) direction with about 1.5V? - Characteristics of GaN FETs and ICs - GaN Talk Support Forum EPC (epc-co.com)