Droplet epitaxy of InGaN quantum dots on Si (111) by plasma-assisted molecular beam epitaxy

• Published in: Discover nano Vol. 18; no. 1; p. 60
• Main Authors: Nurzal, Nurzal, Hsu, Ting-Yu, Susanto, Iwan, Yu, Ing-Song
• Format: Journal Article
• Language: English
• Published: New York Springer US 07.04.2023; Springer Nature B.V
• Subjects: Amorphous alloys; Chemistry and Materials Science; Diffraction patterns; Droplets; Electron diffraction; Electrons; Emissions; Epitaxy; Gallium; Gallium base alloys; High energy electrons; High vacuum; Indium; Indium gallium nitrides; Materials Science; Molecular beam epitaxy; Molecular Medicine; Nanochemistry; Nanoscale Science and Technology; Nanotechnology; Nanotechnology and Microengineering; Optoelectronic devices; Photoelectron spectroscopy; Photoelectrons; Photoluminescence; Photons; Quantum dots; Self-assembly; Substrates; Transmission electron microscopy; Wavelength; InGaN; Molecular beam epitaxy; Droplet epitaxy; Quantum dots; Photoluminescence
• ISSN: 2731-9229; 1931-7573; 2731-9229; 1556-276X
• DOI: 10.1186/s11671-023-03844-2

The droplet epitaxy of indium gallium nitride quantum dots (InGaN QDs), the formation of In–Ga alloy droplets in ultra-high vacuum and then surface nitridation by plasma treatment, is firstly investigated by using plasma-assisted molecular beam epitaxy. During the droplet epitaxy process, in-situ reflection high energy electron diffraction patterns performs the amorphous In–Ga alloy droplets transform to polycrystalline InGaN QDs, which are also confirmed by the characterizations of transmission electron microscopy and X-ray photoelectron spectroscopy. The substrate temperature, In–Ga droplet deposition time, and duration of nitridation are set as parameters to study the growth mechanism of InGaN QDs on Si. Self-assembled InGaN QDs with a density of 1.33 × 10 11  cm −2 and an average size of 13.3 ± 3 nm can be obtained at the growth temperature of 350 °C. The photoluminescence emissions of uncapped InGaN QDs in wavelength of the visible red (715 nm) and infrared region (795 and 857 nm) are observed. The formation of high-indium composition of InGaN QDs via droplet epitaxy technique could be applied in long wavelength optoelectronic devices.