True Alternating Current Scanning Tunneling Microscope (ACSTM): tunneling on insulators

arXiv (Cornell University)

Abstract

Scanning Tunneling Microscopy (STM) has revolutionized our atomic scale understanding of surfaces and accelerated progress in nanotechnology. This technique, however, is restricted to metal or semiconducting samples, as it requires a tiny current to stabilize the tip-sample distance with atomic scale precision. We developed a new imaging and feedback method that relies on true alternating current (AC) without any direct current (DC) component. This technique does not only enable the imaging on non-conducting surfaces with atomic step resolution, like (thin) glass and oxides, it provides also access to high-frequency electronic signal coming from the sample. We demonstrate that it is possible to measure on 25nm thick silicon oxide with 10 MHz tunneling current.

Authors 1

1. M. J. Rost corresponding Aachen Huygens-Kamerlingh Onnes Laboratory

   Leiden University

   Affiliation as printed

   Huygens-Kamerlingh Onnes Laboratory , Leiden University , Niels Bohrweg 2 , 2333 CA Leiden , The Netherlands