7 Editor Comment v2 10/9/09 13:23 Page 7
CONNECTING THE COMPOUND SEMICONDUCTOR COMMUNITY editorialview
September 2009
Volume 15 Number 6
Consultant Editor
Richard Stevenson PhD
richardstevenson@angelbc.co.uk
+44 (0)1291 629640
Editor-in-Chief
David Ridsdale dr@angelbcl.co.uk
+44 (0)1923 690210
Publisher
Jackie Cannon jc@angelbcl.co.uk
+44 (0)1923 690205
Account Handlers
Shehzad Munshi sm@angelbcl.co.uk
+44 (0)1923 690215
Tommy Beazley tb@angelbcl.co.uk
+44 (0)1923 690222 Bolt from the Blue
Design & Production Manager
Mitchell Gaynor mg@angelbcl.co.uk
+44 (0)1923 690214
Most of us delight in watching a great race unfold. There is the thrill of seeing Usain Bolt hurtle
Circulation Director
down the track and smash the world 100 m record, or a great middle-distance runner timing their
Jan Smoothy js@angelbcl.co.uk
kick to perfection, leaving the pack, and crossing the finishing line first. There are also the longer
+44 (0)1923 690200
races – marathons, round-the-world sailing competitions, and first ascents of mountains – that leave
Subscriptions Manager time for leaders to come and go, and those that were once flailing to snatch victory. Our community
Debbie Higham dh@angelbcl.co.uk
+44 (0)1923 690220
also has its races. They include the race for the first blue LED with a p-n junction – a feat
accomplished 20 years ago and recounted in this issue – and the first terahertz laser. But recently,
Commercial Director
the most exciting race has been for the first truly green nitride laser.
Stephen Whitehurst stephen@angelbc.co.uk
+44 (0)2476 718970
I expected Rohm to grab this crown, because it has been the leading light in the push of non-polar
Directors
Stephen Whitehurst, Jan Smoothy
lasers to longer wavelengths. Its rival in this domain, the University of California, Santa Barbara,
Bill Dunlop Uprichard
also had an outside chance, particularly after strengthening its squad by poaching Hiroaki Ohta
Published by
from Rohm about a year ago. And it is always dangerous to write off Nichia – conventional nitride
Angel Business Communications Ltd, lasers appeared to hit a wall at around 490 nm until the company announced a 510 nm variant this
Hannay House, 39 Clarendon Road,
Watford, Herts WD17 1JA, UK
spring, and if they quickly repeated that stretch they could have snatched the title.
T: +44 (0)1923 690200
F: +44 (0)1923 690201
But none of these won - it was Sumitomo of Japan that
Angel Business Communications Ltd
grabbed that accolade with its 531 nm semi-polar laser.
Unit 6, Bow Court, Fletchworth Gate,
This gave me quite a shock, because as far as I’m aware,
Burnsall Road, Coventry CV5 6SP
T: +44 (0)2476 718 970
the company had kept this development under wraps. But
F: +44 (0)2476 718 971
should we really be that surprised? The foundation to
success with polar and semi-polar lasers is a high-quality
Compound Semiconductor is published nine
times a year on a controlled circulation basis.
gallium nitride substrate, and Sumitomo definitely knows a
Non-qualifying individuals can subscribe at:
thing or two about that.
£105.00/€158 pa (UK & Europe), £138.00 pa (air
mail), $198 pa (USA). Cover price £4.50. All
information herein is believed to be correct at Although the race is now over, plenty more work must be
time of going to press. The publisher does not
accept responsibility for any errors and
done before we can go out and buy laser TVs and pocket-
omissions. The views expressed in this sized projectors that feature these sources. Performance
publication are not necessarily those of the
specs will need a massive hike and production costs will
publisher. Every effort has been made to obtain
copyright permission for the material contained
have to fall substantially.
in this publication.
Substrates are one of the biggest barriers to commercial success. I don’t know the size of the
Angel Business Communications Ltd will be
happy to acknowledge any copyright
substrates that Sumitomo used, but I imagine they were comparable to non-polar pieces used by
oversights in a subsequent issue of the
the likes of Rohm that are no bigger than your fingernail. However, there is hope. Mitsubishi is now
publication.
developing 2 inch non-polar GaN substrate production, and if this is successful it will be a very
Angel Business Communications Ltd
welcome breakthrough.
© Copyright 2009. All rights reserved. Contents
may not be reproduced in whole or part
without the written consent of the publishers. Reliability is another massive issue. Aside from Nichia, it never gets a mention in the papers by
The paper used within this magazine is
produced by chain of custody certified
long-wavelength nitride laser developers. And a race for reliability targets is anything but sexy.
manufacturers, guaranteeing sustainable However, if these lasers are going to enjoy commercial success, then it is essential that we also
sourcing.
have a winner in that race category.
Printed by: Pensord Press.
ISSN 1751-1135(Print)
Richard Stevenson PhD
ISSN 2041-1383(Online)
Consultant Editor
September 2009 www.compoundsemiconductor.net 7
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