# Molecular Beam Epitaxy Growth of Scandium Nitride on Hexagonal SiC, GaN, and AlN

## TL;DR

This study demonstrates the growth of cubic Scandium Nitride (ScN) thin films on various hexagonal substrates using RF plasma assisted MBE, revealing novel twinned crystal structures and promising electronic properties.

## Contribution

First observation of cubic twinned patterns in ScN during epitaxy, with detailed structural and electronic characterization on hexagonal substrates.

## Key findings

- Cubic (111) twinned patterns observed in ScN
- High n-type carrier concentration (~1x10^20/cm^3)
- Electron mobility around 20 cm^2/Vs

## Abstract

RF plasma assisted MBE growth of Scandium Nitride (ScN) thin films on GaN (0001)/SiC, AlN (0001)/Al2O3 and on 6H-SiC (0001) hexagonal substrates is found to lead to a face centered cubic (rock-salt) crystal structure with (111) out-of-plane orientation instead of hexagonal orientation. For the first time, cubic (111) twinned patterns in ScN are observed by in-situ electron diffraction during epitaxy, and the twin domains in ScN are detected by electron backscattered diffraction, and further corroborated with X-ray diffraction. The epitaxial ScN films display very smooth, sub nanometer surface roughness at a growth temperature of 750C. Temperature-dependent Hall-effect measurements indicate a constant high n-type carrier concentration of ~1x1020/cm3 and electron mobilities of ~ 20 cm2/Vs.

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Source: https://tomesphere.com/paper/1908.01045