Field-effect transistor

Abstract

A field-effect transistor is made with electrodes ( ) and isolators ( ) in vertically provided layers, such that at least the electrodes ( ) and the isolators ( ) form a step ( ) oriented vertically relative to the first electrode ( ) or the substrate ( ). Implemented as a junction field-effect transistor (JFET) or a metal-oxide semiconducting field-effect transistor (MOSFET) the electrodes ( ) forming respectively the drain and source electrode of the field-effect transistor or vice versa and the electrode ( ) the gate electrode of the field-effect transistor. Over the layers in the vertical step ( ) an amorphous, polycrystalline or microcrystalline inorganic or organic semiconductor material is provided and forms the active semiconductor of the transistor contacting the gate electrode ( ) directly or indirectly and forming a vertically oriented transistor channel ( ) of the p or n type between the first ( ) and the second ( ) electrode. In a method for fabrication of a field effect transistor a vertical step ( ) is formed by a means of a photolithographic process and a soluble amorphous active semiconductor material ( ) is deposited over the first electrode ( ) and the vertical step ( ) such that a vertically oriented transistor channel between the drain and source electrode ( ) is obtained. In a JFET the semiconductor material ( ) contacts the gate electrode ( ) directly. In a MOSFET a vertically oriented gate isolator ( ) is provided between the gate electrode ( ) and the semiconductor material ( ).