Hello all,

I'm simulating a field-plated-GaN-HEMT device. The IdVd characteristics obtained are fine for lower drain voltages. However, for higher drain voltages, the device doesn't enter breakdown. The I-V characteristic continues linearly for drain voltages till infinity.

I have included all models essential for breakdown analysis such as impact selb, field-dependent mobility model (fldmob), fermi and srh.

Further, I am using gummel method for low voltages(