Single crystalline GaSe/WSe2 heterointerfaces grown by van der Waals epitaxy. I. Growth conditions

Abstract
Epitaxial GaSe films have been prepared on WSe2 (0001) substrates with 14% lattice mismatch and characterized by photoelectron spectroscopy, electron diffraction, and ex situ by tunneling microscopy. The films grow in the Frank–van der Merve growth mode. The best films with perfect azimuthal orientation are formed after an annealing step at 720 K. The basic mechanisms of this van der Waals epitaxy are qualitatively discussed in terms of thermodynamic and kinetic parameters.