European researchers demonstrate reliability of IQE grown VCSEL devices at 40 Gbit/s
10 November 2011
Cardiff, UK – 10 November 2011: Researchers working on the European Commission funded Vertically Integrated Systems for Information Transfer (VISIT) programme, for which IQE produces advanced semiconductor wafers, have demonstrated high reliability Vertical Cavity Surface Emitting Laser (VCSEL) devices operating at world record data rates of up to 40 Gbit/s, which is four times faster than the current single channel (serial) data rate used in commercial systems.
VISIT is an EU funded programme with the remit to focus on strategic, high-value photonic components and subsystems for scalable economic broadband access and local area networks. The central objective of the VISIT programme, which start in October 2008, is the research, development, test and exploitation of system-enabling optical transmitters having a completely novel design and/or largely improved functionality as compared to current technology.
The directly modulated VCSEL devices fabricated on material grown by IQE at its Cardiff facility operate at 850nm, which is the current standard wavelength for optical fibre applications used in short-reach data communication and storage area networks.
The new technology increases data throughput by up to 400 times the speed of current copper Ethernet systems and four times that of the latest optical technologies. The VISIT researchers demonstrated VCSEL devices operating at data rates of up to 30 Gbit/s at 85˚C, and up to 40 Gbit/s at 25˚C with bit error ratios of less than 10E-12, which for many data communication applications is considered “error-free.”
The VCSEL devices also demonstrated superb temperature stability in the linear region of the light power versus current characteristic with a less than 25 µW/˚C change in emission power for operation below 6 mA at temperatures between 20 to 100˚C. The peak output power exceeded 8 mW for multi-mode operation and up to 4 mW for single mode operation, all with differential slope efficiencies exceeding 70% at up to 40˚C.
Multi-mode VCSEL device operation was demonstrated at current densities well below 10 kA/cm2 which is a critical factor in determining device reliability. This is expected to greatly improve with the further development of single-mode VCSELs.
The VISIT team has also produced the first 40 Gbit/s packaged VCSELs, complete with an OM3 fibre pigtail and a high frequency electrical V-connector for ease of system-level optical link testing and development.
The prototype VCSEL devices fabricated using new device processing techniques and device geometries on wafers produced by IQE’s optoelectronic facility in Cardiff, UK, operated reliably at 40 Gbit/s in initial tests, making them suitable for optical interconnectors as well as for optical fibre networks for high data rate applications such as data centres.
The next development stage under the VISIT programme will focus on final directly modulated VCSEL benchmarking and design and processing refinement including device designs for reliability and manufacturability. The VISIT team will also work on further improvements in the packaging and testing of optical transmitter subassemblies.
The VISIT Project is funded by the European Commission Framework 7 Programme with Project Officer Dr. Michael Hohenbichler. The project is led by Prof. Dr. Dieter Bimberg of the Technical University of Berlin (Germany), and includes also the following project partners: IQE (UK), Intel Performance Learning Solutions Ltd. (Ireland), VI Systems GmbH (Germany), Chalmers University of Technology (Sweden), The University of Cambridge (UK), University College Cork via the Tyndall National Institute (Ireland), , Riber S.A. (France),and the A.F. Ioffe Physical-Technical Institute of the Russian Academy of Sciences (Russia).
Technical/Sales: IQE Europe (+44 29 2083 9400) Andrew Joel Stephen Phelps
Press: IQE plc (+44 29 2083 9400) Chris Meadows
Note to Editors
IQE is the leading global supplier of advanced semiconductor wafers with products that cover a diverse range of applications, supported by an innovative outsourced foundry services portfolio that allows the Group to provide a 'one stop shop' for the wafer needs of the world's leading semiconductor manufacturers.
IQE uses advanced crystal growth technology (epitaxy) to manufacture and supply bespoke semiconductor wafers ('epi-wafers') to the major chip manufacturing companies, who then use these wafers to make the chips which form the key components of virtually all high technology systems. IQE is unique in being able to supply wafers using all of the leading crystal growth technology platforms.
IQE's products are found in many leading-edge consumer, communication, computing and industrial applications, including a complete range of wafer products for the wireless industry, such as mobile handsets and wireless infrastructure, Wi-Fi, WiMAX, base stations, GPS, and satellite communications; optical communications. The Group also manufactures advanced optoelectronic and photonic components such as semiconductor lasers, vertical cavity surface emitting lasers (VCSELs) and optical sensors for a wide range of applications including optical storage (CD, DVD, BluRay), thermal imaging, leading-edge medical products, pico-projection, finger navigation ultra high brightness LEDs, and high efficiency concentrator photovoltaic (CPV) solar cells.
The manufacturers of these chips are increasingly seeking to outsource wafer production to specialist foundries such as IQE in order to reduce overall wafer costs and accelerate time to market.
IQE also provides bespoke R&D services to deliver customised materials for specific applications and offers specialist technical staff to manufacture to specification either at its own facilities or on the customer's own sites. The Group is also able to leverage its global purchasing volumes to reduce the cost of raw materials. In this way, IQE's outsourced services, provide compelling benefits in terms of flexibility and predictability of cost, thereby significantly reducing operating risk.
IQE operates eight facilities located in Cardiff (two), Milton Keynes and Bath in the UK; in Bethlehem, Pennsylvania, Somerset, New Jersey and Spokane, Washington in the USA; and Singapore. The Group also has 11 sales offices located in major economic centres worldwide.