To improve emission stability and realize low rum-on voltage, a silicon field emitter controlled by a metal-oxide-semiconductor field effect transistor (MOSFET) was fabricated and demonstrated. The emitter cathode was fabricated in the n-well drain of the MOSFET on ap-type Silicon substrate. In addition to the: extraction gate, another electrode was introduced as the MOSFET＇s control gate. This gate＇s oxide thickness was designed to be thinner than that Of the extraction gate for low turn-on voltage; Furthermore, two types of drain structure were adopted to compare device reliability with regard to impact ionization effect. Experimental results showed that emission current was effectively controlled by the MOSFET at;a gate voltage of less than 5 V. It was found that impact ionization was caused near the drain edge, where a high electric field was concentrated, in the conventional drain structure. Consequently, MOSFET characteristics were significantly influenced.