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Light emitting diodes (LEDs) based on In(x)Gal(1-x)N (x = 0.15-0.2)/GaN multiple-quantum wells ( MQWs) have been grown on sapphire substrates. Their wavelength emission can be tuned from blue to orange by increasing the QW thickness. This opens the way for ...
A FIA method has been developed and fully characterized for the simultaneous detection of ammonia and glutamine in culture media. Ammonia detection is based upon a chem. method and does not require an electrode. This species diffuses across a hydrophobic p ...
Microcavity light emitting diodes (MCLEDs) present several interesting features compared to conventional LEDs such as narrow linewidth, improved directionality and high efficiency. We report here on MCLEDs with a top emitting geometry. The MCLED layers wer ...
GaInN/GaN heterostructures have been grown by molecular beam epitaxy (MBE) on c-plane sapphire substrates. The growth of Ga1-xInxN (x > 12%) alloy has been extensively studied. At low V/III ratio, the growth undergoes a Stranski-Krastanov transition giving ...
The use of photonic crystals (PCs) for realistic light emitting diodes (LEDs) is discussed, given the constraints of planar semiconductor technology. A viable route for the fabrication of high-efficiency high-brightness electrically injected LEDs is presen ...
Fully processed VLSI GaAs MESFET circuits, available through the MOSIS service, have recently been shown to be electrically stable after 3-h thermal cycles at 500-degrees-C. It is therefore feasible to epitaxially regrow photonic device heterostructures di ...
The lack of appropriate substrates has delayed the realisation of devices based on III-nitrides. Currently, the heteroepitaxial growth of GaN by metal organic vapour phase epitaxy (MOVPE) produces GaN layers which, despite huge densities of dislocations, a ...
GaN based LEDs are grown on sapphire by MBE using NH3. The n- and p-type doping levels are 4x10(18) and 3x10(17) cm(-3), respectively. LEDs turn on at 3V, and the forward voltage is 3.7V at 20mA. The electroluminescence peaks at 390 nm. ...
III-V nitrides LEDs were grown on c-plane sapphire substrates by molecular beam epitaxy using NH, as nitrogen precursor and solid sources for group-III elements. LEDs based on GaInN/GaN multiple quantum well structures were fabricated. Their electrolumines ...
GaN and InGaN alloys were grown on c-plane sapphire substrates by molecular beam epitaxy using NH3. This allows realizing light emitting diodes (LEDs) based on InGaN/GaN single heterostructures. The forward voltage is 3.6 V at 20 mA. The room temperature e ...
