A Field-Effect Transistor (FET)

1. Has three PN -junctions
2. Incorporates a forward-biased junction
3. Depends on the variation of a magnetic field for its operation
4. Depends on the variation of the depletion-layer width with reverse voltage, for its operation

The field-effect transistor (FET) operation depends on the variation of the depletion-layer width with reverse voltage, for its operation.