Xiangqian Xiu - IEEE Xplore Author Profile

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We have fabricated the InGaN/AlGaInN multiple quantum wells with lattice-matched AlGaN/InGaN superlattices barriers (SL-MQWs). The lattice-matched superlattices promote the formation of the high-quality MQWs and eliminate the large polarization electric field. Highly excited photoluminescence measurement is performed by Ti-sapphire pulse laser with the maximal carrier density of 1020 cm-3. Under s...Show More
This study designed and tested an innovative light-emitting diode (LED) chip with a built-in sensor. Two electrically isolated units, the LED (for light emission) and the sensor (for monitoring junction temperature and light intensity), were integrated on a single chip. The sensor unit determines the junction temperature by measuring the forward voltage; the light output power of the LED unit can ...Show More
We report on the photoluminescent characteristics of InGaN/GaN multiple quantum well (MQW) embedded in nanostructures with different porosity. The best one is the nanorod structure which shows 1.75 times of planar structure on quantum efficiency.Show More
In this work, the composition distribution in SiC films grown on Si(111) using chemical vapor deposition (CVD) method has been measured by the plan-view energy dispersive spectroscopy (EDS). The measuring original EDS data are modified by considering the multilayer structure and the attenuation due to the diffuse reflection at the interface of the voids. The relative error rate of the improved EDS...Show More
The frequency dependence of capacitance-voltage (C-V) characteristics of Hg/GaN and Hg/InGaN/GaN Schottky contacts are investigated for 1KHz, 10KHz and 1MHz at room temperature. An anomalous peak in the C-V curves of Hg/GaN sample is observed but no peak for the Hg/InGaN/GaN sample occurs. The interface states, series resistance and minority-carrier injection would be the origin of this anomalous ...Show More
We report the first demonstration of a GaN-based planar metal-semiconductor-metal (MSM) ultraviolet (UV) avalanche photodiode (APD). The MSM APD with semitransparent interdigitated Schottky electrodes is fabricated on a low-defect-density GaN homoepitaxial layer grown on a bulk GaN substrate by metal-organic chemical vapor deposition. The dislocation density of the GaN homoepilayer characterized b...Show More
In this paper, the k- p perturbation theory is adopted to calculate the interband excitonic transition energies and their polarization selection rules in c-plane A1N films, GaxAl1-xN and InxAl1-xN alloys modulated by both isotropic biaxial in-plane strain and alloy compositions. It is shown that valence band mixing induced by both strain and alloy composition has dramatic influence on the optical ...Show More
Schrodinger equation and Poisson equation are solved self-consistently for Al0.5Ga0.5N/GaN heterojunctions grown along the c axis, then the distribution of electrons and the exact energy of all the bounded states confined in heterojunctions are gotten, and the electrons are found to take up the first two subbands. Considerable magnitude of Rashba spin splitting for the first subband at the Fermi l...Show More
The technique of indium droplets catalyst is used for the synthesis of InN nanodots on (0001) sapphire substrates via metalorganic chemical vapor deposition (MOCVD) technique using trimethyindium (TMIn: (CH/sub 3/)/sub 3/In) and NH/sub 3/, The morphology evolution of the InN nanodots are studied by AFM. The structure of the prepared sample is characterized by X-ray diffraction (XRD) and Raman scat...Show More
Un-doped and 5% Co-doped ZnO powders were prepared by sol-gel method using Zn(CH/sub 3/COOH)/sub 2//spl middot/2H/sub 2/O and Co(CH/sub 3/COOH)/sub 2//spl middot/2H/sub 2/O as starting precursors and ethanol as a solvent, the powders were heated at 550/spl deg/C for 30 minutes in air. In this paper, using methods such as X-ray diffraction (XRD), Raman and vibrating sample magnetometer (VSM), we ha...Show More
The oxidation of InN and In-rich InN films grown on (0001) sapphires by low-pressure MOCVD has been investigated. X-ray diffraction (XRD) measurements show that stoichiometric InN is difficult to be oxidized at the temperature lower than 400/spl deg/C. However, nonstoichiometric In-rich InN can be oxidized at low temperature even as low as 300/spl deg/C. And In-rich InN films are fully oxidized at...Show More
Thick GaN films grown with different V/III ratio on sapphire by hydride vapour phase epitaxy have been investigated. The V/III ratio is changed from 240 to 30. All the GaN films, which are n type, show only (0002) oriented peak and have the band emission with no yellow luminescence bands. When V/III ratio is 30, the full width at half maximum of (0002) X-ray rocking curve is the smallest, line-wid...Show More
N-type GaN films grown by Hydride Vapor Phase Epitaxy technique were etched under different conditions at room temperature. Direct evidence of etch-stop effect of dislocations during photoelectrochemical (PEC) etching has been found. Further investigation of the mechanism has been discussed.Show More
Gallium Nitride films grown on sapphire substrates were successfully separated by laser radiation. The absorption of the 248 nm radiation by the GaN at the interface results in rapid thermal decomposition of the interfacial layer, yielding metallic Ga and N/sub 2/ gas. The substrate can be easily removed by heating above the Ga melting point of 30/spl deg/C. Atomic force microscopy, X-ray diffract...Show More