Effects of conduction type on field-electron emission from single Si emitter tips with extraction gate

Field emission characteristics from n- and p-type silicon gated emitter tip s have been investigated in detail by means of experiments and theoretical estimation of band bending induced by surface states. Single-tip emitters h ave been fabricated from n- and p-type silicon and their current-voltage ch aracteristics have been evaluated. The field emission from the p-type emitt er has been found to occur at a lower extraction voltage than that of the n -type emitter. As the theoretical approach to the origin of the phenomena, potential distribution in the emitter tips has been calculated by using a d evice simulation technique. The surface states of the n-type emitter tip ar e negatively charged and form a potential barrier against the electrons. On the contrary, there is no potential barrier in the p-type tips. The potent ial barrier in the n-type tip prevents electrons from reaching the tip apex . This is the reason why the emission current of the n-type emitter was sup pressed lower than that of the p-type emitter. (C) 2000 American Vacuum Soc iety. [S0734-211X(00)04202-5].