We fabricated oxidized porous polysilicon (OPPS) field emitters to apply a large device using a metal bottom electrode instead of the n+ doping method and in process condition below 600C. An OPPS field emitter that has minute pixel structures was operated by individual unit pixels. A non-doped polysilicon layer 1.5m was deposited on tungsten as a bottom electrode and anodized to form OPPS structures in a solution of HF (49%): ethanol in a 1:1 ratio for the porous process and 1M H2SO4 for the electrochemical oxidation (ECO). The porous process and ECO process for poly-silicon were performed with various current densities and process times due to altered polysilicon film properties. The highest emission efficiency was investigated when the porous condition was 5mA/cm2, 5 sec and the oxidation process was 5mA/cm2, 30sec.