FABRICATION OF A SILICON-VACUUM FIELD-EMISSION MICRODIODE WITH A MOVING ANODE

A vacuum microdiode with a moving anode was fabricated by means of a n ew process requiring only two mask levels and only one critical etchin g step. The cathode, with a pyramidal shape, was made by anisotropical ly etching p silicon through a mask formed by the anode itself, which, at the end of the process, consists of a SiO2 suspended membrane supp orting an Al layer. The process is compatible with standard complement ary metal-oxide-semiconductor technology. I-V characteristics were mea sured under vacuum verifying also that the diode current is sensitive to visible light irradiation and to changes of the anode-to-cathode di stance. A minimum anode-cathode distance of about 5000 Angstrom was ob tained. (C) 1998 American Vacuum Society. [S0734-211X(98)03902-X].