Spinoidal Doping Structures in Sulfurized Molybdenum Carbide

Nanometer scale control of doping variations is a key part of the development of nanoscale electronics. In this talk, we report results of STM and AFM investigations of spatial doping variations in sulfurized MoC. We find that highly doped regions appear in a spinodal pattern, and that although the surface of the material remains atomically flat, these large doping variations lead to apparent height changes of up to one nanometer in STM topographs, with sharp transitions between doped and undoped regions, giving the appearance of pits. We will discuss the impact of these doping variations on local density of states measurements, their interplay with Moire patterns, and their evolution with further sulferization.