Temperature Control System for Fabrication of W-microprobes

Electrochemical etching is one of the most popular methods to fabricate micro and nanoscale metal (usually tungsten) probes to be used in the fields of electrical characterization, scanning tunneling microscopy, scanning probe lithography, healthcare, etc. Temperature of the electrolyte is one of the key parameters that decide the diameter and profile of the probe tip. A rapid change in the temperature of electrolytes causes an unwanted profile and larger tip diameter of the probe. In this paper we report a simple and low-cost feedback-based temperature control system to maintain the temperature at a desired value. We demonstrate electrochemical etching of W wire using the developed (in-house) temperature control system and have fabricated micron scale sharp probe tips which are used for a novel scanning probe-based lithography technique - electrolithography.