Field emission vacuum microelectronic devices, which operate at a low voltage, require sharp cathode tips and minimal cathode to anode spacing. Using high resolution electron beam lithography in combination with reactive ion etching technique, lateral multi-tip diodes have been fabricated with cathode to anode spacings less than 40nm. The devices were measured in ultra high vacuum chamber which was pumped down to $3×10^{-9}$ Torr. The electrical characteristics show low voltage operation and the linearity of the Fowler-Nordheim plots provides another confirmation of field emission. Triodes have been fabricated by adding a gate electrode between cathode and anode electrodes. After the emission currents of the fabricated devices versus time under $V_A=30V$ for 2hours, the maximum current fluctuation was 0.2%.