Understanding the 2D-material and substrate interaction during epitaxial growth towards successful remote epitaxy: a review

Abstract

Remote epitaxy, which was discovered and reported in 2017, has seen a surge of interest in recent years. Although the technology seemed to be difficult to reproduce by other labs at first, remote epitaxy has come a long way and many groups are able to consistently reproduce the results with a wide range of material systems including III-V, III-N, wide band-gap semiconductors, complex-oxides, and even elementary semiconductors such as Ge. As with any nascent technology, there are critical parameters which must be carefully studied and understood to allow wide-spread adoption of the new technology. For remote epitaxy, the critical parameters are the (1) quality of two-dimensional (2D) materials, (2) transfer or growth of 2D materials on the substrate, (3) epitaxial growth method and condition. In this review, we will give an in-depth overview of the different types of 2D materials used for remote epitaxy reported thus far, and the importance of the growth and transfer method used for the 2D materials. Then, we will introduce the various growth methods for remote epitaxy and highlight the important points in growth condition for each growth method that enables successful epitaxial growth on 2D-coated single-crystalline substrates. We hope this review will give a focused overview of the 2D-material and substrate interaction at the sample preparation stage for remote epitaxy and during growth, which have not been covered in any other review to date. Graphical Abstract

Determination of the preferred epitaxy for III-nitride semiconductors on wet-transferred graphene

“…This may be due to that the relatively low growth temperature limits the in-plane twist of the remote epitaxial grains to some extent, and MBE had a stronger ability to regulate the growth kinetics of III-nitride than MOCVD at low growth temperature. The structural damage caused by the N-plasma source in MBE ( 46 ) and the interference of the interfacial oxidation layer ( 47 , 48 ) can be avoided by using MOCVD since the latter growth is performed at high temperatures as high as ~1000°C under hydrogen-containing ambient. In this case, the remote epitaxial grains on graphene show spontaneously twist and thus form a polycrystalline film ( Figs.…”

Perspectives for III-nitride photonic platforms

“…More interestingly for heterogeneous integration, the direct or in situ epitaxial growth of 2D materials offers much more simplicity and opportunities [142]. These 2D materials can be either hexagonal BN (h-BN), graphene or transition metal dichalcogenides (TMDs) [143] but many more materials can be envisioned. Epitaxially-aligned MoS 2 on GaN has been reported for example in [144] and in [145] with epitaxial growth by chemical vapor deposition.…”

Unveiling the mechanism of remote epitaxy of crystalline semiconductors on 2D materials-coated substrates

“…When the interacting force from the underlying substrate is stronger than the vdW force from the top 2D layer, the crystalline substrate remotely dictates the crystallographic registration (i.e., crystal symmetry and orientation) of the epilayer through 2D material. It is called “remote epitaxy” [ 84 , 85 ]. Such long-range force through the 2D layer is discussed with regard to polarity formed by bonding ionicity [ 86 ].…”