Pradeep Namboodiri1 Xiqiao Wang1 Gheorghe Stan1 Jonathan Wyrick1 Scott Schmucker1 Ranjit Kashid1 Roy Murray1 Michael Stewart Jr1 Richard Silver1

1, National Institute of Standards and Technology, Gaithersburg, Maryland, United States

Scanning probe microscopies, with their ability for atomic scale resolution imaging and patterning, are expected to enable fabrication of quantum electronic devices at scales never achievable before. Atomically precise patterning of a hydrogen passivated Si (100) surfaces by a scanning tunneling microscope (STM) allows selective doping to fabricate planar nanowires and quantum dots. These devices are then encapsulation by an epitaxial layer of Si. A key challenge in this method is locating the encapsulated devices and aligning electrical contacts to them with a high degree of accuracy. Kelvin Probe Force Microscopy (KPFM), which enables nanometer-scale imaging of the surface potential, is capable of imaging encapsulated Phosphorous devices. Based on topography and surface potential images acquired simultaneously, we can locate devices with respect to the etched fiducial marks, and then align and fabricate electrical contacts using an e-beam lithography tool. The presentation will focus mainly on subsurface imaging of buried devices and a strategy for aligning electrical contacts to STM patterned devices using KPFM.