Dopant Enhanced Etching of TiSe₂ by Scanning Tunneling Microscopy

Abstract

The surfaces of pure and Mn doped TiSe(2) were etched using a scanning tunneling microscope. Both types of samples were found to etch easily when scanning was performed in ambient conditions. This process was enhanced at step edges or other surface defects. In pure samples, material was removed in a layer-by-layer fashion with a strong dependence on the scanning direction of the tip. Doped samples etched far more rapidly, to the point that stable scanning conditions were difficult to establish. Doped samples also showed a greater number of pits and other defects on their surface. A relatively small percentage of dopants was necessary to strongly impact the surface topography and stability. These results show that impurities can play a dominant role when using scanning tunneling microscopy to create surface nanostructures.

Electrical Stressing Induced Monolayer Vacancy Island Growth on TiSe2

“…It is only through preferential edge vacancy generation that we are able to explain the nonlinear vacancy island area growth with respect to time, though many other vacancy source mechanisms were explored (including uniform bulk vacancy generation, as discussed earlier). Although, similar vacancy growth has already been seen on some TMDs through both STM and AFM measurements. − To our knowledge, this is the first time a direct correlation between preferential electrical stressing at vacancy island edges and the observed growth rate has been established.…”

“…Although similar vacancy growth has already been seen on some TMDs through both STM and AFM measurements [33][34][35][36][37][38][39][40][41][42]. It is the first time that a direct correlation between preferential electrical stressing at vacancy island edges and the observed growth rate has been established.…”

Coulomb-driven cluster-glass behavior in Mn-intercalated Ti1+yS2

“…The fabrication details have been discussed in previous publications. 6,20 After growth, the structural properties of the samples were investigated with powder x-ray diffraction (PXRD) and energy dispersive x-ray spectroscopy (EDX). The PXRD measurements were taken with Cu Kα radiation on finely ground powder that had been passed through a 200-mesh (75-micron) sieve.…”