TY  - JOUR
AU  - Lüpke, Felix
AU  - Just, Sven
AU  - Bihlmayer, Gustav
AU  - Lanius, Martin
AU  - Luysberg, Martina
AU  - Doležal, Jiří
AU  - Neumann, Elmar
AU  - Cherepanov, Vasily
AU  - Ošt'ádal, Ivan
AU  - Mussler, Gregor
AU  - Grützmacher, Detlev
AU  - Voigtländer, Bert
TI  - Chalcogenide-based van der Waals epitaxy: Interface conductivity of tellurium on Si(111)
JO  - Physical review / B
VL  - 96
IS  - 3
SN  - 2469-9950
CY  - Woodbury, NY
PB  - Inst.
M1  - FZJ-2017-06569
SP  - 035301
PY  - 2017
AB  - We present a combined experimental and theoretical analysis of a Te rich interface layer which represents a template for chalcogenide-based van der Waals epitaxy on Si(111). On a clean Si(111)-(1×1) surface, we find Te to form a Te/Si(111)-(1×1) reconstruction to saturate the substrate bonds. A problem arising is that such an interface layer can potentially be highly conductive, undermining the applicability of the on-top grown films in electric devices. We perform here a detailed structural analysis of the pristine Te termination and present direct measurements of its electrical conductivity by in situ distance-dependent four-probe measurements. The experimental results are analyzed with respect to density functional theory calculations and the implications of the interface termination with respect to the electrical conductivity of chalcogenide-based topological insulator thin films are discussed. In detail, we find a Te/Si(111)-(1×1) interface conductivity of σTe2D=2.6(5)×10−7S/□, which is small compared to the typical conductivity of topological surface states.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000405023400007
DO  - DOI:10.1103/PhysRevB.96.035301
UR  - https://juser.fz-juelich.de/record/837709
ER  -