Highly forward-biased FET gates and their experimental current and voltage distributions.

Experimental results agree with the assumption that the current density along the gate decreases linearly, which is valid for the low gate metalization sheet resistances commonly used. The d.c. potential distributions along gates of different length, width and metalization, of GaAs MESFETs have been probed, using a fine whisker probe, with the gate Schottky diode under forward bias conditions. A linear decrease of the current density along a gate has been verified, leading to a variation of the voltage along the gate of the form x(1-x). It was found, that only below a gate length of approx. 1 mym the gate resistance determined by the Schottky diode forward bias method corresponds to the d.c. gate resistance.