Harmonic distortion in the junction field-effect transistor with field-dependent mobility
It has been found that a harmonic analysis of the usual power-law transfer characteristic of the JFET does not yield equations which accurately predict the third-harmonic distortion products for short-gate structures. However, if field-dependent mobility in the drain-source channel is taken into consideration in the equations for the drain- current, a transfer characteristic is obtained of the form 3zD(1-e-r)Γ2, where zD is the normalized channel height and Γ is the field factor. Equations for the distortion products M2 and M3, which are derived from this type of characteristic, accurately predict M2 and M3 for actual devices as a function of physical parameters. Lower limits on the values of M2 and M3 which can be achieved in a practical JFET are presented
