A new metal-oxide-semiconductor field-effect-transistor-structured Si field emitter tip

A new current-controllable silicon field emitter tip with a metal-oxide-semiconductor field-effect-transistor (MOSFET) structure is proposed and demonstrated. The device has a simple structure in which a conical Si tip is made in the drain region of a MOSFET. The gate plays two roles; one is that of a conventional extraction electrode and the other is that of a control gate for the drain current supplied to the tip. Experimental results showed that the emission current was well controlled by the drain current at a gate voltage of around 80 V. Quite stable emission of about 0.8 mu A was obtained with a single tip at the above gate voltage.