Static and dynamic properties of the dual-gate metal-oxide-semiconductor transistor

Description of the static and dynamic behavior of the dual-gate MOS transistor on the basis of the physical mechanisms governing its operation. Following a review of the main properties of a model of the variable-mobility MOS transistor, a method of determining the relations between current and voltages in the MOS tetrode is proposed which likens the tetrode to an association of two MOS transistors in series with a common substrate. A study is made of the various modes of operation of the tetrode which correspond to pinched or unpinched states for each of the elementary components of this cascode device. A theoretical determination is made of the elements of the admittance matrix associated with the active zone of the conduction channel when allowance is made for the combined action of the two components of the electric field on the carrier-mobility reduction. Following a brief description of the parasitic elements which figure in the operation of a real tetrode, a high-frequency model is proposed for identifying these elements. Finally, an analysis is made of the power gain properties of the tetrode.