ALD is now set up as a strong candidate to realise ALD indium nitride based electronics

Research from Linköping University in Sweden headed by Prof. Henrik Pedersen paves the way for ALD is now set up as a strong candidate to realise ALD indium nitride based electronics. 

Direct epitaxial nanometer-thin InN of high structural quality on 4H–SiC by atomic layer deposition 

Appl. Phys. Lett. 117, 093101 (2020); https://doi.org/10.1063/5.0014900

 

Indium nitride (InN) is a highly promising material for high frequency electronics given its low bandgap and high electron mobility. The development of InN-based devices is hampered by the limitations in depositing very thin InN films of high quality. We demonstrate growth of high-structural-quality nanometer thin InN films on 4H–SiC by atomic layer deposition (ALD). High resolution x-ray diffraction and transmission electron microscopy show epitaxial growth and an atomically sharp interface between InN and 4H–SiC. The InN film is fully relaxed already after a few atomic layers and shows a very smooth morphology where the low surface roughness (0.14 nm) is found to reproduce sub-nanometer surface features of the substrate. Raman measurements show an asymmetric broadening caused by grains in the InN film. Our results show the potential of ALD to prepare high-quality nanometer-thin InN films for subsequent formation of heterojunctions.

Prof. Henrik Pedersen: Very happy that our paper "Direct epitaxial nanometer-thin InN of high structural quality on 4H–SiC by #ALDep" is published as an Editor's Pick in Applied Physics Letters. Great work by Chih-Wei Hsu and Dr. Petro Deminskyi and excellent TEM by Justinas Palisaitis. ALD is now set up as a strong candidate to realise InN based electronics.

X-ray diffractograms of 2θ-ω scan of InN films grown with different numbers of ALD cycles on 4H–SiC (0001). The number of ALD cycles and their corresponding film thicknesses determined by fringes are indicated, respectively, in the plot. The curves are plotted on the log scale and are shifted vertically for visual clarity. (Image from LinkedIn)