In the first follow up to the successful inaugural Compound Semiconductor Industry Awards, Thorsten Matthias, Thomas Uhrmann, Chad Brubaker and Paul Lindner of EV Group discuss their award winning temporary bonding system
When the order books swell to breaking point, chipmakers can go and build a new fab. But isn’t it better for them to hold on to their cash and find a foundry partner that replicates in-house processing and provides a second source of product manufacture? This is the Anadigics’ way, say the company’s Dan Stofman and Kevin Chang, who tell the story behind implementing this strategy.
Contacts, transparent conductive oxides and reflective coatings influence the performance of cutting-edge high-brightness LEDs. Each of these requires thin-film deposition, which can be realised by either using a collection of batch tools to process a set of wafers in single process steps, or a by employing a far more integrated cluster tool to handle a single wafer in a whole series of process steps. Allan Jaunzens from Evatec outlines the merits and drawbacks of both approaches.
At RFMD, we have upgraded our BiFET technology, replacing the JFET device that allowed integration of new DC circuits with a D-mode pHEMT. The result: more efficient products offering greater functionality.
Researchers from Boston College and MIT have turned to nanotechnology to achieve a 60-90% increase in the thermoelectric figure of merit (ZT) of a p-type quinary compound semiconductor known as a half- Heusler.
Silicon is the entrenched electronic technology in solar cell inverters, hybrid electric vehicles, aircraft landing gear, deep-drilling tools and audiophile amplifiers. But its vice-like grip on these markets looks set to slip as SemiSouth ramps production of its high-voltage SiC diodes and transistors that will underpin improvements in efficiency, reliability and linearity. Richard Stevenson reports.
Nitride lasers, which are a key component in Blu-ray players and recorders, still suffer from limited reliability. The origin of this failure is controversial, but there is strong evidence to suggest that point defects are to blame, argues Matteo Meneghini, Nicola Trivellin, Gaudenzio Meneghesso and Enrico Zanoni from University of Padova, Italy.
Extracting the very best performance from a triple junction photovoltaic demands optimisation of the absorption edge of every sub-cell. Incorporating quantum wells into the cells can realise this, while allowing the device to be tailored for the spectral conditions where it will be deployed, say QuantaSol’s Keith Barnham, Alison Dobbin, Matt Lumb and Tom Tibbits.
Greater levels of GaAs integration in tomorrow’s smartphones, initial deployment of green nitride lasers in mobile pico-projectors and the insertion of high-modulation InP lasers and novel memories to slash power consumption in next-generation supercomputers were all on the agenda at CS Europe. Richard Stevenson reports.
Conducting polymers such as polythiophenes promise to replace metallic films for charge dissipation in semiconductor processing. This switch should provide ease of use and deliver results of unprecedented quality, say Rafal Dylewicz and Faiz Rahman from the University of Glasgow, UK.
Conventional multi-junction cell measurements only yield the characteristics of the entire device. In stark contrast, a novel electroluminescence approach can probe far deeper, extracting the current-voltage curves for individual sub-cells that hold the key to optimising the overall conversion efficiency, say the technique’s pioneers, Raymond Hoheisel, Sebastian Rönsch, Frank Dimroth and Andreas Bett from the Fraunhofer Institute for Solar Energy Systems and Helmut Nesswetter and Claus Zimmermann from EADS Astrium.
Process engineers put down nitride films by cranking MOCVD reactors up to 1100°C and cracking ammonia and metal precursor molecules on the substrate. But this type of growth can be performed at far lower temperatures to create epitaxial films with minimal hydrogen by switching to a table-top Nanomaster tool that employs an RF source to split nitrogen gas into a plasma. Richard Stevenson talks to Nanomaster’s CEO, Birol Kuyel, about the pros and cons of this alternative growth technology.
One option for maintaining the march of Moore’s Law is to build the pairing of III-V and germanium transistors on silicon. Depositing compound semiconductors on silicon in a selective manner is tricky, but researchers at imec have shown that it is possible to do this on 200 mm on-axis wafers by forming concave trenches in the material, before filling them with a little germanium and topping them up with InP. Richard Stevenson reports.
The combination of reliable output powers of 7W, peak power conversion efficiencies in excess of 60 percent and spectral widths below 1nm can be realized by incorporating integrating distributed feedback gratings into broad-area lasers, says Paul Crump from the Ferdinand Braun Institut, Germany.