Nanophotonics is one of the most exciting new fields to come out of nanotechnology. The quantum-confinement effects observed in these very small (~10 nm) particles can lead to unique optical properties.
Photoluminescence spectroscopy (PL) is a powerful optical method used for characterizing materials. PL can be used to find impurities and defects in silicon and group III-V element semiconductors, and to determine semiconductor band-gaps.
High-Resolution Low-Temperature PL of Semiconductors
Temperature-dependent photoluminescence (PL) spectroscopy is a powerful optical method for
characterizing materials. PL can be used to identify defects and impurities in Si and III-V semiconductors, as well as determine semiconductor bandgaps. At room temperature, PL emission is usually broad—up to 100 nm in width.
As a result of rapid development in semiconductor manufacturing, many types of optoelectronic
devices such as laser diodes, LEDs, and high-electron-mobility transistors (HEMTs) are now fabricated by epitaxial-growth methods.
Gallium Nitride (GaN) is one of a generation of promising light-emitting materials. Its direct energy band gap of ~3.4 eV at room temperature make it particularly suitable for emission in the blue, and near UV spectral ranges. The material often exhibits high temperature stability and low electrical leakage, and hence GaN is generally a good candidate for fabricating high-temperature and high-power devices.
Characterization of Semiconductors with Photoluminescence Measurement System
Photoluminescence is the optical emission obtained by photon excitation (usually a laser) and is commonly observed with III-V semiconductor materials. This type of analysis allows non-destructive characterization of semiconductors (material composition, qualitative investigations, etc.
III-V Wafer Characterization through Photoluminescence Mapping
III-V semiconductors are important to the fabrication of active photonic devices such as light sources and detectors. Successful fabrication of such devices relies on the high quality of the underlying materials and precise deposition of intended geometries on a wafer substrate.
Room-temperature Micro-electroluminescent Characterization of Ge-based IR Sources
Monolithic integration of optical components on CMOS platforms is ongoing in the optical communications industry. CMOS offers a mature and robust platform, and therefore is logical for building optical-interconnect modules.
Photoluminescence Characterization of GaN Alloys and Other Semiconductor Microstructures
GaN and related alloys are important materials used to build short-wavelength light sources (lasers and LEDs). Room- and low-temperature photoluminescence (PL) are used to characterize these materials as well as device performance.
Effect of temperature on HSA structure inferred using timeresolved room-temperature phosphorescence
To access intrinsic amino acids, such as tryptophan, as probes, the UV excitation wavelengths for pulsed phosphorescence measurements have long been the preserve of low-repetition-rate gas-filled lamps or larger laser systems. Recent developments have enabled the use of interchangeable semiconductor diodes...
HORIBA Jobin Yvon’s NanoLog® spectrofluorometer, specially optimized for recording near-IR fluorescence from nanoparticles, includes a double-grating excitation monochromator, imaging emission spectrograph with a selectable-grating turret, and a variety of detectors.
Evaluation of Novel Photoresponsive Materials via EQE Measurements
Internal Quantum Efficiency (IQE) and External Quantum Efficiency (EQE) measurements are indicators of the effectiveness of a photosensitive device such as those used in telecommunications and solar cells. EQE is the ratio of the charges generated to the total amount of photons incident on the surface; a larger EQE indicates a more efficient device.
Tryptophan phosphorescence within protein molecules is gaining attention as a probe of protein dynamics and structure. The tryptophan phosphorescence lifetime, τ, varies with the protein molecule’s local environment and conformation.
Among the possible fluorescence biosensors for medical and biochemical monitoring and imaging are the flavonoids, compounds that occur in many plants and their products, such as tea, chocolate, and red wine.