Establishing Epitaxial Connectedness in Multi-Stacking: The Survival of Thru-Holes in Thru-Hole Epitaxy

TL;DR

This paper uses Monte Carlo simulations to explore how thru-holes in layered 2D masks can persist through multiple stacking layers, enhancing epitaxial connectedness in thru-hole epitaxy.

Contribution

It introduces a simulation-based analysis of hole survival mechanisms in multi-stack 2D epitaxial growth, clarifying the conditions for maintaining thru-holes.

Findings

Highly anisotropic holes improve survival rates

Thru-holes can be maintained through multiple stacks with proper shape

Epitaxial connectedness is supported by thru-hole survival

Abstract

Thru-hole epitaxy has recently been reported to be able to grow readily detachable domains crystallographically aligned with the underlying substrate over 2D mask material transferred onto a substrate. [Jang \textit{et al.}, \textit{Adv. Mater. Interfaces}, \textbf{2023} \textit{10}, 4 2201406] While the experimental demonstration of thru-hole epitaxy of GaN over multiple stacks of $h$-BN was evident, the detailed mechanism of how small holes in each stack of $h$-BN survived as thru-holes during multiple stacking of $h$-BN was not intuitively clear. Here, we use Monte Carlo simulations to investigate the conditions under which holes in each stack of 2D mask layers can survive as thru-holes during multiple stacking. If holes are highly anisotropic in shape by connecting smaller holes in a particular direction, thru-holes can be maintained with a high survival rate per stack, establishing more epitaxial connectedness. Our work verifies and supports that thru-hole epitaxy is attributed to the epitaxial connectedness established by thru-holes surviving even through multiple stacks.