AN INSTRUMENT FOR INVESTIGATING HIGH-ELECTRIC-FIELD PHENOMENA AT SMALL ELECTRODE SEPARATIONS

An instrument with the tip positioning capability of a scanning tunnel ing microscope and the imaging capability of a field emission electron microscope has been developed. This instrument provides the ability t o investigate the current-voltage characteristics of field emitter tip s in the metal-vacuum, transition, and metal-vacuum-metal tunneling re gimes. It also allows a field emitter tip to be imaged before and afte r these ''close approach'' measurements are made. Nonreproducible tunn eling characteristics observed in the transition region have been asso ciated with large changes in the apex of the field emitter tip. (C) 19 98 American Institute of Physics.