MANUFACTURE OF NIOBIUM PROBE FOR SCANNING TUNNELING MICROSCOPE

摘要

PROBLEM TO BE SOLVED: To provide a manufacturing method for a niobium probe for scanning tunneling microscope capable of improving the position resolution at the time of STM observation. SOLUTION: A niobium wire (a purity of 99.9%) of 0.3 mm diameter is used as a probe material 2, while a hydrochloric acid aqueous solution of 25% concentration is used as an electrolytic solution 1. As a counter electrode 3, a flat plate electrode is used. By immersing the probe material 2 into the electrolytic solution 1 and applying an AC voltage of 30V between the probe material 2 and the counter electrode 3 from an AC power supply 4, electropolishing is executed. Then, an application voltage is dropped to 2 V in several steps. When the whole part of the probe material 2 immersed in the electrolytic solution 1 dissolves and the tip of a probe becomes separate from the liquid surface of the electrolytic solution 1, current stops and electrolytic etching automatically finishes.