Electron field emission from polycrystalline silicon tips

Arrays of 10 polysilicon field emitter tips were fabricated using plasma et ch and oxidized to form sharp tips. Phosphorus doped polysilicon tips emit at around 10-15 V regardless of the degree of their sharpness. Similarly, i ntrinsic polysilicon tips emit at around 50 V (at 2 mu m tip to anode spaci ng). The same turn on voltages have been observed on Hat polysilicon surfac es. Field emission data of the diode structures revealed a significant diff erence between phosphorous doped and intrinsic polysilicon tips and flat su rfaces. The phi(3/2)/beta versus applied voltage was obtained from the tran sconductance data and was used to compare the performance of the doped and intrinsic polysilicon tips. A qualitative comparison of phi(3/2)/beta ratio reveals an increase in the effective work function of the intrinsic polysi licon device which is related to the field penetration inside the emitting surfaces. Furthermore, field emission data reveal the conduction limitation of the intrinsic polysilicon films associated with the single carrier inje ction mechanism. (C) 2000 American Vacuum Society. [S0734-211X(00)08402-X].