FEATURES
| Displaying 1 - 20 of 1570 |
|
Analysts address the big issues at CS International
May 24, 2013
The impact of Qualcomm’s CMOS amplifier on the GaAs RF market, the steps that must be taken to make LED light bulbs affordable, and the most likely path that will be taken to enable the introduction of power electronics in the grid were all discussed by leading market analysts at CS International. Richard Stevenson reports.
Boosting GaN-on-silicon blocking voltages
May 20, 2013
A misconception is holding back the development and deployment of GaN devices that are built on silicon substrates. This platform is widely blamed for compromising blocking voltages, but it doesn’t: It is possible to make diodes and HEMTs on silicon that have breakdown voltages of well over 2 kV, according to Timothy Boles and Douglas Carlson from M/A-COM Technology Solutions, Tomas Palacios from MIT and Mike Soboroff from the US Department of Energy.
Strategies for enhancing photovoltaic performance
May 15, 2013
There are many options for improving the performance of III-V solar cells, including inserting quantum wells and dots to extend spectral coverage and adding nanoparticles and diffraction gratings to boost light trapping. Insights into all these approaches are outlined by Sudha Mokkapati, Samuel Turner, Haofeng Lu, Lan Fu, Hark Hoe Tan and Chennupati Jagadish from The Australian National University
Graphene-on-SiC heads from lab to fab
May 09, 2013
To fulfil the tremendous potential of graphene, high-quality material must be shipped in significant volumes. One supplier looking to do just that is Graphensic, which has developed graphene-on SiC products for making structures for metrology, high-speed transistors and biosensors. Company founders Rositza Yakimova, Mikael Syväjärvi, and Tihomir Iakimov detail their progress.
Kyma eyes new opportunities with a broadened product portfolio
May 03, 2013
Diversification lies at the heart of Kyma Technologies’ vision for its future. It first made a name for itself as a leading supplier of wide bandgap materials, but it is now expanding its offerings and has starting to provide plasma vapour deposition (PVD) equipment and photoconductive switches, explains the company chief executive officer, Keith Evans.
Increasing the versatility of photonic integrated circuits
Apr 29, 2013
Photonic integrated circuits enable the construction of compact, highly functional components, but operation tends to be restricted to telecom wavelengths. We are now addressing this shortcoming by developing devices that operate further into the infrared, say imec’s Dries Van Thourhout and Gunther Roelkens.
Vertical integration streamlines sapphire production
Apr 23, 2013
It’s great for business to adopt a holistic approach to sapphire manufacturing. When a firm begins with the processing of raw materials and ends with wafer polishing, it enables a trimming of manufacturing costs, the application of proprietary processes to many steps used in sapphire substrate production, and improvements to the reliability of product supply, argues Raja Parvez from Rubicon Technology.
German efforts advance semi-polar materials
Apr 17, 2013
Lasers and LEDs that are grown on semi-polar planes deliver very impressive performance at green wavelengths, but commercial success of these devices is hampered by a lack of affordable, high-quality substrates with appropriate orientations. To address this, a German team is developing various methods to make semi-polar material, and studying its properties in detail. Richard Stevenson reports.
LED droop: Direct Auger gets the blame
Apr 15, 2013
Direct Auger recombination causes droop, but its impact can be diminished inserting graded layers into quantum wells to smooth the confining potentials.
Slashing the cost of solid-state lightings
Apr 11, 2013
How can LED epiwafers costs fall to a level that can spur mass adoption of solid-state lighting? By turning to growth on 200 mm silicon substrates, loaded into a multi-wafer MOCVD reactor equipped with advanced thermal management and optimised wafer recesses, argues Aixtron’s Boerge Wessling.
Commercial status of the GaN-on-silicon power industry
Mar 28, 2013
Firms developing and producing GaN-on-silicon devices for the power electronics industry come in many different flavours. Some sell on the open market; some just ship to a chosen few; others offer foundry services; and there are also those that form partnerships. Zel Diel, Managing Director of Venture-Q LLC, considers these various approaches and their implications, before looking at how far companies have progressed towards commercialization of their technology.
Tandem solar cells are set to benefit from surface activated bonding
Mar 27, 2013
Surface activated bonding of GaAs and silicon substrates can yield high-quality heterojunctions, according to electrical characterization and microscopy.
Tiny LEDs produce intense, directional emission
Mar 25, 2013
Multiple markets beckon for substrate-emitting, miniature LEDs
Electron-beam lift-off : Collection Efficiency and Paths to Improvement
Mar 22, 2013
Liftoff coatings require specific rules of deposition (normal or 90o) incidence angle be maintained to prevent metal deposition onto resist via sidewalls.
Simplifying the growth of m-plane GaN
Mar 21, 2013
Growth of non-polar GaN on m-plane sapphire is realized without buffer layers and nitridation processes
Following an electron’s journey through a GaN HEMT
Mar 18, 2013
Impact ionization, carrier trapping and leakage paths prevent the channels in today’s HEMTs from providing great transport links between their sources and drains. But improvements should follow, now that these maladies can be exposed with optical and electrical techniques, argue Nicole Killat and Martin Kuball from the University of Bristol.
Panasonic’s non-polar LEDs combine efficiency and power
Mar 15, 2013
Wide quantum wells that are free from internal electric fields combat droop and enable high efficiencies at high drive currents
Maverick manufacturing anomalies: What threat to reliability?
Mar 14, 2013
Even veterans of reliability measurements struggle to provide customers with predictions of the future reliability of a lot that exhibits early fallout in the factory. That’s because, until recently, it’s been very difficult to gather the data needed to respond with a specific and satisfying answer, says Bill Roesch from TriQuint Semiconductor.
Accounting for droop with Auger recombination and polarization fields
Mar 07, 2013
Minimizing polarization fields in LEDs fails to enhance quantum efficiency
GaAs lasers eye multiple targets
Feb 26, 2013
Infrared edge emitters and VCSELs are targeting a growing number of lucrative markets: Gaming, ultra-high density data storage, finger navigation and optical cables for USB and HDMI interconnects. Oclaro’s Robert Blum and Karlheinz Gulden discuss them all in detail.
Displaying 1 - 20 of 1570 |
|
