Yuhuai Liu 교수

A monolithic multicomponent system is proposed and implemented on a III-nitride-on-silicon platform, whereby two multiple-quantum-well diodes (MQW-diodes) are interconnected by a suspended waveguide. Both MQW-diodes have an identical low-In-content InGaN/Al_0.10Ga_0.90N MQW structure and are produced by the same fabrication process flow. When appropriately biased, both MQW-diodes operate under a simultaneous emission-detection mode and function as a transmitter and a receiver

Thick AlN crystals were grown by conventional hydride vapor phase epitaxy (HVPE) on AlN/sapphire templates under low pressure (∼15 Torr) at high temperature (1100°C–1200°C). Colorless, mirror-like AlN films were obtained at the growth rates of up to 20.6 µm/h. The best root mean square (RMS) value of atomic force microscope (AFM) observations for the AlN surface was 2.34 nm. The typical values of full width half maximum (FWHM) of X-ray rocking curves for (0002) and (1012) diffraction of AlN film

Abstract A film stripping method that allows for liquid phase exfoliation assisted by spin coating polymethyl methacrylate has been investigated, resulting in a two‐inch hexagonal boron nitride (hBN) film to be fully stripped and then transferred. A number of key factors that can influence the stripping and the transferring process of the films grown by sputtering have been systematically analyzed, including different solutions, different concentration of solution and different thickness of film

The multiple functionalities of III-nitride semiconductors enable the integration with different components into a multicomponent system with enhanced functions. Here, we propose to fabricate and characterize a monolithic InGaN photonic circuit of a transmitter, waveguide, and receiver on an III-nitride-on-silicon platform. Both the transmitter and the receiver, sharing identical InGaN/GaN multiple-quantum-well structures and fabrication procedures, work to emit light and detect light independen

Abstract Aluminium (Al) composition is a critical parameter of performance for deep ultraviolet (DUV) AlGaN devices. In multiple-quantum-wells (MQW) nanowire laser diode, quantum barriers play an important role in carriers’ flow (electrons, holes). In this work, the impact of composition, and the thickness of AlGaN-based quantum barriers is being studied. The study suggests that by properly increasing Al composition of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <

We report here a GaN-based resonant cavity light-emitting diode (RCLED) with top and bottom dielectric TiO2/SiO2 distributed Bragg reflector (DBR) mirrors on a silicon substrate. High data transmission in free space at 200 Mbps with an opening in the eye diagram was achieved. The results show that the combination of GaN-based LED on silicon and double sided dielectric DBR mirror deposition enables a manufacturable process which provides a unique opportunity for commercialization of RCLED in futu

The design of the active region structures, including the modifications of structures of the quantum barrier (QB) and electron blocking layer (EBL), in the deep ultraviolet (DUV) AlGaN laser diode (LD) is investigated numerically with the Crosslight software. The analyses focus on electron and hole injection efficiency, electron leakage, hole diffusion, and radiative recombination rate. Compared with the reference QB structure, the step-like QB structure provides high radiative recombination and

We propose two composition-graded quantum barriers (QBs) to improve the performance of AlGaN-based deep ultraviolet laser diodes (DUV-LDs). The optical and electrical properties of three LDs containing conventional QBs, graded increased QBs, and graded decreased QBs were numerically investigated. It was found that the LDs with graded decreased QBs significantly improved the carrier injection efficiency, raised the carrier concentration in the active region, reduced the carrier leakage, and enhan