Bottom‐Up Nano‐heteroepitaxy of Wafer‐Scale Semipolar GaN on (001) Si

Abstract

Semipolar {101¯1} InGaN quantum wells are grown on (001) Si substrates with an Al-free buffer and wafer-scale uniformity. The novel structure is achieved by a bottom-up nano-heteroepitaxy employing self-organized ZnO nanorods as the strain-relieving layer. This ZnO nanostructure unlocks the problems encountered by the conventional AlN-based buffer, which grows slowly and contaminates the growth chamber.

Nanostructured InGaN Quantum Wells as a Surface-Enhanced Raman Scattering Substrate with Expanded Hot Spots

“…Figure (a) shows the sectional schematic diagram of the SERS substrate built by InGaN QWs. The columnarized structure stems from the core–shell ZnO-GaN nanorods, which is employed to release the strain of GaN-on-Si via three-dimensional (3D) lattice deformation. As displayed in the scanning electron microscopy (SEM) image in Figure (b), the tip-to-tip spacing of the nanopyramids is below 1 μm, and the diameters of the Au nanoparticles are in the range of 10–100 nm.…”

“…The thickness of the InGaN wells was decided not to exceed the critical value on GaN, beyond which threading dislocations and other crystal defects will occur to release huge lattice strain between InGaN and GaN. The nanostructured QWs were achieved with a bottom-up nanoheteroepitaxy method, enabling a roughened surface morphology on the entire 2-inch wafer . Details on the crystal growth and characterization are given in our previous report .…”

“…The nanostructured QWs were achieved with a bottom-up nanoheteroepitaxy method, enabling a roughened surface morphology on the entire 2-inch wafer . Details on the crystal growth and characterization are given in our previous report . Before the growth, ZnO nanorods were synthesized on the Si substrate using the hydrothermal method .…”

Effects of NH3 Flow Rate on the Growth Mechanism and Optical Properties of InN Crystallites Fabricated by Chemical Vapor Deposition

“…In recent years, substantial research has been focused on the promising optoelectronic properties of Group III nitrides (XN, X = In, Ga, Al). − Because of the wide band gap range (0.68–6.2 eV), XN and their related alloys have been demonstrated with the emission range from UV to IR. − They are commonly used for fabricating light-emitting diodes (LEDs) with many advantages such as long lifetime, low power consumption, and more environmentally friendly compared to the traditional light source . Considering other remarkable properties like large piezoelectric coefficients and high chemical inertness, XN materials have also emerged as promising candidates for applications in water splitting, high-electron-mobility transistors, and piezotronics .…”

Three-Dimensional Hetero-Integration of Faceted GaN on Si Pillars for Efficient Light Energy Conversion Devices

“…Such integration would combine the superior optoelectronic properties of III–V materials and the well-established Si-based semiconducting technologies. − Most studies have been focusing on solving the challenge that III–V materials and Si have significant lattice and thermal mismatches. To solve the mismatch issues, many strategies have been attempted, including low-temperature nucleation, , insertion of intermediate layers between active III–V materials and Si substrates, ,− and growing III–V materials on three-dimensional (3D) Si crystal arrays at nano- and microscales. − However, in addition to heteroepitaxial growth, cost-effective light energy conversion devices will also require effective light managing structures. Here, we report the successful heteroepitaxial growth of faceted GaN crystals on tapered micron-sized Si pillars, and the resulting 3D structure exhibits excellent light managing properties.…”