HETEROEPITAXY OF A TWO-DIMENSIONAL MATERIAL ON A 3-DIMENSIONAL MATERIAL

An ultra-thin single-crystal film of MoSe2 has been proved to grow heteroepitaxially on a clean CaF2(111) substrate, regardless of the large difference in the crystal structures and of the lattice mismatch which is as large as 17%. It results from the fact that the CaF2(111) surface is very inert because of the termination of active bonds by regularly arrayed F atoms on the top layer, onto which heteroepitaxy proceeds by van der Waals forces in the same way as the van der Waals epitaxy between layered materials. It has opened a new way to grow a variety of heterostructures made of various layered materials on a three-dimensional material substrate. © 1989.