Oriented Two-dimensional Semiconducting Crystals on Amorphous Dielectrics by Selective Artificial Epitaxy

Abstract Defective grain boundaries form in semiconductors when deposition approaches do not control crystal grain orientation. This poses existential limitations to fabricating highly performing semiconductor devices with two-dimensional semiconductors for industry’s future Angstrom technology nodes. Today’s monolithic or bottom-up deposition methods do not control crystal grain orientation on industry-standard substrates covered with amorphous dielectrics due to lack of crystallographic symmetry provided by the substrate. Here, we report selective artificial chemical vapor epitaxy of tungsten disulfide (WS₂), an approach to orient two-dimensional crystals on amorphous substrates with nanopatterns. Amorphous nanopatterns with axial symmetry that mimics the trigonal crystallographic symmetry of the WS₂ crystal lattice guide WS₂ crystal orientation as well as location. We show a proof of concept in a 300 mm industrial pilot-line at back-end-of-line compatible deposition temperature. This monolithic concept opens possibilities to eliminate grain boundaries and deposit single-crystalline two-dimensional materials directly on conventional amorphous dielectrics at feature scales relevant for most advanced device architectures.