P-44: Optimization and Characterization of the Porous Poly-silicon Emitter

It is estimated that a porous polysilicon (PPS) diode with a structure of Au/PPS/n‐type Si operates as an efficient stable surface emitting cold cathode. 2.0 μm of an nondoped polysilicon layer is formed on an heavily doped n‐type silicon wafer and anodized in a solution of HF(50%): ethanol = 1: 1 under illumination by a 500 W tungsten lamp from a distance of 20 cm. The electron emission properties of the PPS diode were investigated as a function of anodizing condition. It was found that the electron emission properties depend on the anodizing condition, and the optimum anodizing condition is 10mA/cm2 for 15 seconds. The PPS diode emitter fabricated by using the optimum condition has higher efficiency, lower diode current and higher emission current compared to that of other PPS diode emitter. The electron emission characteristics as a function of ambient pressure and the electron trajectory were also studied. Furthermore, the fluctuation properties of the PPSE was investigated and discussed.