Current collapse in AlGaN/GaN HFETs is investigated at low temperatures using a transient current monitoring technique. The carrier trapping and detrapping mechanisms are studied, and two distinct relaxation mechanisms are observed. They are associated to the presence of two close deep energy levels in the bandgap.

www.rsc.org/MaterialsA We proposed in our previous work V-substituted ln2S3asan intermediate band (IB) material able to enhance the efficiency of photovoltaic cells by combining two photons to achieve a higher energy electron excitation, much like natural photosynthesis. Here this hyper-doped material is tested in a photocatalytic reaction using wavelength-control led light. The results evidenc...

We theoretically investigate highly tensile-strained Ge nanowires laterally on GaSb. Finite element method has been used to simulate the residual elastic strain in the Ge nanowire. The total energy increment including strain energy, surface energy, and edge energy before and after Ge deposition is calculated in different situations. The result indicates that the Ge nanowire on GaSb is apt to gr...

iron oxide (fe2o3) is widely used as a catalyst, pigment and gas sensitive material.  in this article, α-fe2o3 nano-rods were first synthesized via a simple chemical method using iron(iii) nitrate 9- hydrate (fe(no3)3.9h2o) as precursor. xrd pattern showed that the iron oxide nanoparticles exhibited alpha-fe2o3 (hematite) structure in nanocrystals. the single-phase α- fe2o3 nano-rods were prepa...

Mixed-phase hydrogenated silicon oxide (SiOx:H) is applied to thin-film hydrogenated amorphous silicon germanium (a-SiGe:H) solar cells serving as both p-doped and n-doped layers. The bandgap of p-SiOx:H is adjusted to achieve a highly-transparent window layer while also providing a strong electric field. Bandgap grading of n-SiOx:H is designed to obtain a smooth transition of the energy band e...

Recognized as technologically important materials for optoelectronics, III-nitride wide-bandgap semiconductors are used in light-emitting diodes (LEDs) with emission wavelengths from the ultraviolet to amber, and blue/UV-emitting laser diodes.1 These materials are excellent for photonic devices because of their large energy bandgaps, their highly efficient light emission, and their ability to b...

We demonstrate that the ultrafast fast dynamics of the d-f exchange interaction, between conduction band electrons and lattice spins in EuTe, can be accessed using an all-optical technique. Our results reveal, in full detail, the time evolution of the d-f exchange interaction induced by a femtosecond laser pulse. Specifically, by monitoring the time resolved dynamics of the reflectivity changes...

A sub-1V bandgap voltage reference (BGVR) in 0.16μm CMOS is presented that circumvents the trade-off between area and power consumption in conventional sub-1V BGVR topologies. This circuit can be used in systems to generate reference voltages locally, eliminating the conventional relatively large BGVR and its global reference voltage distribution interconnect. The active area is 0.0025mm; at 29...

Zinc oxysulfide nanocrystals with zinc blende phase are synthesized through a wet-chemical method. An affirmation of the crystal structure, elemental homogeneity and phase transformation is obtained by X-ray diffraction and authenticated by electron micrographic studies. Theoretical observations have strongly supported the thermodynamic solubility limit for its (30%) formation. An anomalous ban...

In this paper, a new photonic gated-diode method is proposed to extract the energy-dependent and spatial distributions of interface states in MOSFETs. For the photonic current–voltage (I–V) characterization of MOSFETs, an optical source with a photon energy less than the silicon bandgap (hν=0.95eV<Eg=1.12eV) is employed for the characterization of interface states (Eit) distributed in the photo...