Optimization of internal quantum efficiency (IQE) for InGaN quantum wells (QWs) light-emitting diodes (LEDs) is investigated. Staggered InGaN QWs with large electron-hole wavefunction overlap and improved radiative recombination rate are investigated for nitride LEDs application. The effect of interface abruptness in staggered InGaN QWs on radiative recombination rate is studied. Studies show t...

Three-dimensional hierarchical nanostructures were synthesized by the halide chemical vapor deposition of InGaN nanowires on Si wire arrays. Single phase InGaN nanowires grew vertically on the sidewalls of Si wires and acted as a high surface area photoanode for solar water splitting. Electrochemical measurements showed that the photocurrent density with hierarchical Si/InGaN nanowire arrays in...

InGaN-based light-emitting diodes (LEDs) have been widely accepted as highly efficient light sources capable of replacing incandescent bulbs. However, applications of InGaN LEDs are limited to small devices because their fabrication process involves expensive epitaxial growth of InGaN by metalorganic vapor phase epitaxy on single-crystal wafers. If we can utilize a low-cost epitaxial growth pro...

Nanostructure (NS) InGaN crystals were grown on carbon nanotubes (CNTs) using metalorganic chemical vapor deposition. The NS-InGaN crystals, grown on a ~5-μm-long CNT/Si template, were estimated to be ~100-270 nm in size. Transmission electron microscope examinations revealed that single-crystalline InGaN NSs were formed with different crystal facets. The observed green (~500 nm) cathodolumines...

Self-assembled InGaN quantum dots were grown in the Stranski–Krastanov mode by plasma-assisted molecular beam epitaxy. The average dot height, diameter and density are 3 nm, 30 nm and 7 × 1010 cm–2, respectively. The dot density was found to decrease as the growth temperature increases. The cathodoluminescence emission peak of the InGaN/GaN multiple layer quantum dots (MQDs) was found to red sh...

Numerical simulations are conducted to study the current-matching effect and operation mechanisms in and to design the optimized device structure of InGaN/Si tandem cells. The characteristics of short circuit current density (J sc), open circuit voltage (V oc), fill factor (FF), and conversion efficiency (η) of InGaN/Si tandem cells are determined by the current-matching effect. The similar tre...

ZnO/InGaN/GaN heterostructured light-emitting diodes (LEDs) were fabricated by molecular beam epitaxy and atomic layer deposition. InGaN films consisted of an Mg-doped InGaN layer, an undoped InGaN layer, and a Si-doped InGaN layer. Current-voltage characteristic of the heterojunction indicated a diode-like rectification behavior. The electroluminescence spectra under forward biases presented a...

Defect formation and In segregation in InGaN/GaN quantum wells grown at various temperatures and with various well thicknesses were studied using cathodoluminescence, transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HR-TEM). In 0.16 Ga 0.84 N quantum wells with In compositional nonuniformity and a small number of structural defects originating at the ...

We have used high resolution transmission electron microscopy (HRTEM), aberration-corrected quantitative scanning transmission electron microscopy (Q-STEM), atom probe tomography (APT) and X-ray diffraction (XRD) to study the atomic structure of (0001) polar and (11-20) non-polar InGaN quantum wells (QWs). This paper provides an overview of the results. Polar (0001) InGaN in QWs is a random all...

To enhance lasers’ power and improve their performance, a model wasapplied for the waveguide design of 400 nm InGaN/InGaN semiconductor laser, whichis much easier to implement. The conventional and new laser structures weretheoretically investigated using simulation software PICS3D, which self-consistentlycombines 3D simulation of carrier transport, self-heating, and opt...