Current Paths in an Atomic Precision Advanced Manufactured Device Imaged by Nitrogen Vacancy Diamond Magnetic Microscopy

Atomic-precision (AP) Si:P D-doped materials are a channel to new microelectronics technologies based on quantum-confined 2D electron- transport in Si. Critical questions include where current flow is actually occurring in or near AP structures. To identify flow and leakage paths, we performed ensemble Nitrogen-Vacancy (NV) wide-field magnetic imaging of current densities, J, in AP material, over a mm-field of view with µm-resolution.  AP material was patterned into Hall-effect devices shaped like mm-sized ribbons. We integrated the AP device with the diamond sensor, a bulk diamond having a 12C enriched, 4 μm-thick, NV ensemble on the surface. Then, we used an NV wide-field magnetometer to map the magnetic (B) field from J flowing through these devices. From the B-field map we reconstructed the J density vector field, which allowed us to detect device failures, such as choke points where flow is impeded, as well as current leakage paths. We found that transport is predominantly 2D, highly confined to the AP doping with small vicinal leakage while choke points result from materials defects. Our results bode well for leveraging extreme lithographic precision of AP devices in technologies at T≥300K.

SNL is managed and operated by NTESS under DOE NNSA contract DE-NA0003525