Atomic-scale patterning of hydrogen terminated Ge(001) by scanning tunneling microscopy

Abstract

In this paper we demonstrate atomic-scale lithography on hydrogen terminated Ge(001). The lithographic patterns were obtained by selectively desorbing hydrogen atoms from a H resist layer adsorbed on a clean, atomically flat Ge(001) surface with a scanning tunneling microscope tip operating in ultra-high vacuum. The influence of the tip-to-sample bias on the lithographic process have been investigated. Lithographic patterns with feature-sizes from 200 to 1.8 nm have been achieved by varying the tip-to-sample bias. These results open up the possibility of a scanning-probe lithography approach to the fabrication of future atomic-scale devices in germanium.

Programmable graphene nanobubbles with three-fold symmetric pseudo-magnetic fields

“…1). Due to the low Ge–H bond energy 18 , the hydrogen atoms desorb easily as a local stimulus with negative bias is applied by AFM tip, then evolve into hydrogen molecules 19,20 . Enveloped by the impetrative monolayer graphene, GNBs filled with the released hydrogen molecules will form subsequently as schematically illustrated in Fig.…”

Dihydride structures of deuterium on germanium (001) surfaces

“…5 Hydrogenating Ge surfaces has attracted wide attention as a method to reduce surface/interface defects density and a method for atomic-scale patterning. 6 With regard to hydrogen adsorption, the surface structure of Ge (001) is considered to be similar to that of Si (001). A structure of monohydride p(2 Â 1) surface is formed in which one hydrogen atom binds to either of the two Ge atoms that form a dimer on the c(4 Â 2) reconstructed surface.…”

Optical in situ monitoring of hydrogen desorption from Ge(100) surfaces

“…Comparison of evaluated values for the activation energy and the pre-exponential factor of H desorption evaluated at different photon energies reflects that H unevenly affects the shape of the RA spectrum. In the last years, there has been a renewed interest in the characterization of the structural and chemical properties of germanium (100) substrates for applications in microelectronics, 1 nanotechnology, 2 and photovoltaics. [3][4][5][6] A suitable surface preparation (in terms of surface cleanliness, termination, and reconstruction) is crucial for subsequent material and device properties.…”