Tuning Optoelectronic Properties of 4H-SiC QDs Using -H, -OH and -F Surface Functionalisation

Marzaini Rashid; Amit Kumar Tiwari; Neal Wood; Patrick Briddon; Jonathan P. Goss; M.J. Rayson; Nick Wright; Alton B. Horsfall

doi:10.4028/www.scientific.net/MSF.821-823.375

Paper Titles

Structural Perfection of Silicon Carbide Crystals Grown on Profiled Seeds by Sublimation Method
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Ab Initio Calculations of Absolute Surface Energies of Clean and Hydrogen Covered 3C-SiC(001), (110) and (111) Surfaces
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Starting Point of Step-Bunching Defects on 4H-SiC Si-Face Substrates
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Surface Orientation Dependence of SiC Oxidation Process Studied by In Situ Spectroscopic Ellipsometry
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Tuning Optoelectronic Properties of 4H-SiC QDs Using -H, -OH and -F Surface Functionalisation
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SiC Device Manufacturing: How Processing Impacts the Material and Device Properties
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Basal Plane Dislocations Created in 4H-SiC Epitaxy by Implantation and Activation Anneal
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Estimation of Phosphorus-Implanted 4H-SiC Layer Recrystallization by Electron-Back-Scattering Diffraction Pattern Analysis
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Ohmic Contact on n-Type 3C-SiC Activated with SiO₂ Encapsulation
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HomeMaterials Science ForumMaterials Science Forum Vols. 821-823Tuning Optoelectronic Properties of 4H-SiC QDs...

Tuning Optoelectronic Properties of 4H-SiC QDs Using -H, -OH and -F Surface Functionalisation

Abstract:

Density functional calculations were performed for the –H, –OH and –F functional groups adsorbed onto the surface of pseudo-spherical 4H-SiC quantum dots with diameters ranging from 10 to 22 Å. We find that for the investigated diameter range, the H-terminated SiC-quantum dots exhibit strong size dependent quantum confinement effects, while for –F and –OH terminations, the optical gap remains largely unchanged. The –H termination shows an optical absorption onset well above that of –F and –OH for a similar cluster size, which is attributed to the localisation of HOMO and LUMO states to the quantum dot core. Based on our calculations, we suggest that the –H functionalisation is a more promising route for engineering the optical properties of SiC-quantum dots, since this could lead to a wider control over the optical absorption onsets, when compared to –OH and –F terminations.