Preparation of STM tungsten probe by electrochemical liquid membrane etch-ing
High quality probe is the key to ensure 4K resolution of the scanning tunneling microscope(STM).In order to obtain atomic-scale probe,the tungsten probe was prepared by vertical liquid membrane method based on electrochemical etching principle.The influence of etching voltage and tungsten wire length on the quality of the probe was studied by control variable method.The results showed that,when using 2 mol/L NaOH solution as the liquid membrane,the best etching voltage was 5 V,and the best length of tungsten wire was 4 mm.This study has provided reference for the preparation of tungsten probe by electrochemical liquid membrane etching.