This diode operation mainly depends on the range of doping in the PN junction. For a little reverse bias voltage, the depletion region is extremely thin & the electric field is extremely high. It permits the electrons to flow from the valence band to the conduction band. The Zener diodes br...
There is a PN junction between the source and drain, so the S and D poles can be identified based on the difference in the positive and negative resistances of the PN junction. For example, an IRFPC50 VMOS tube is measured with a 500-type multimeter R×1 file, and RDS(on)=3.2W, w...