CONNECTING THE COMPOUND SEMICONDUCTOR COMMUNITY
July 2011 Volume 17 Number 5
Editor-in-Chief David Ridsdale
+44 (0)1923 690200
Consultant Editor Richard Stevenson PhD
richardstevenson@angelbc.co.uk +44 (0)1291 629640
News Editor
Dr.Su Westwater
suwestwater@angelbc.co.uk
Director of SOLAR & IC Publishing Jackie Cannon
+44 (0)1923 690205
Account Manager Shehzad Munshi
+44 (0)1923 690215 Robin Halder
+44 (0)2476 718109
USA Representatives Brun Media Tom Brun
Tel: 724 539-2404 Janice Jenkins
Tel: 724-929-3550
Director of Logistics Sharon Cowley
+44 (0)1923 690200
Design & Production Manager Mitchell Gaynor
+44 (0)1923 690214
Circulation Director Jan Smoothy
+44 (0)1923 690200
Subscriptions Manager Debbie Higham
+44 (0)1923 690220
Chief Operating Officer Stephen Whitehurst
stephen.whitehurst@angelbc.com +44 (0)2476 718970
Directors
Bill Dunlop Uprichard – CEO Stephen Whitehurst – COO Jan Smoothy – CFO Jackie Cannon, Scott Adams, Sharon Cowley, Sukhi Bhadal
Published by
Angel Business Communications Ltd, Hannay House, 39 Clarendon Road, Watford, Herts WD17 1JA, UK T: +44 (0)1923 690200 F: +44 (0)1923 690201
Angel Business Communications Ltd Unit 6, Bow Court, Fletchworth Gate, Burnsall Road,Coventry CV5 6SP T: +44 (0)2476 718 970 F: +44 (0)2476 718 971
Compound Semiconductor is published eight times a year on a controlled circulation basis. Non-qualifying individuals can subscribe at: £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 time of going to press. The publisher does not accept responsibility for any errors and omissions. The views expressed in this publication are not necessarily those of the publisher. Every effort has been made to obtain copyright permission for the material contained in this publication. Angel Business Communications Ltd will be happy to acknowledge any copyright oversights in a subsequent issue of the
publication.Angel Business Communications Ltd © Copyright 2011. All rights reserved. Contents may not be reproduced in whole or part without the written consent of the
publishers.The paper used within this magazine is produced by chain of custody certified manufacturers, guaranteeing sustainable sourcing.
US mailing information: Compound Semiconductor (ISSN 1096-598X) is published 8 times a year Jan/Feb, March, April/May, June, July,August/September, October, November/December for a subscription of $198 by Angel Business Communications Ltd, Hannay House, 39 Clarendon Road,Watford, Herts WD17 1JA, UK. Periodicals postage paid at Rahway,NJ. POSTMASTER: send address changes to: Compound Semiconductor, c/o Mercury International Ltd, 365 Blair Road,Avenel, NJ 07001
Printed by: Pensord Press. ISSN 1096-598X (Print) ISSN 2042-7328 (Online) © Copyright 2011.
debbie.higham@angelbc.com jan.smoothy@
angelbc.com
But – and it’s a big but – dilute nitrides are incredibly difficult to grow, which goes some way to accounting for their modest commercial success. This is illustrated in the histories of three long-wavelength dilute nitride laser pioneers, Infineon, Picolight and Optical Communications Products, whose technologies now rest with Alight, JDSU and Oplink, respectively. These new owners say very little about their dilute nitride devices – I’ll leave you to decide what that may say about the successes that they are having.
Meanwhile, the progress of dilute nitride LEDs has suffered from the folding of its leading pioneer, Quanlight.
On the transistor front things are better - Kopin has been offering this technology for several years. However, it is not disclosing how much commercial success it is enjoying with this class of device.
In stark contrast to all these firms, West-coast start-up Solar Junction is actively engaging with the media about its dilute nitride product – a triple junction cell with a dilute nitride base layer. However, given that it is in the process of trying to raise capital to vastly expand its manufacturing capacity, its openness is to be expected.
Solar Junction turned to dilute nitrides to improve cell performance in the infrared, a move that has paid dividends on overall device efficiency. This Stanford spin-off currently holds the world record for efficiency at high concentrations of 43.5 percent, and it has a road map to get to 50 percent.
In an interview with Solar Juntion (see p. 18 of this issue), the founders claimed that their higher cell efficiencies give the company a massive advantage over the incumbents, such as Spectrolab and Emcore. According to their own modelling, cells that outperform all alternatives by a few percent can deliver such a big benefit at the system level that they can price competitors out of the market.
It’s certainly a bold claim from Solar Junction, and one that will not be tested until this outfit has won capital, built a bigger fab and started shipping these products in high volumes. But if it can do all this, it will certainly be a success story for the dilute nitrides that will be worth shouting about.
Richard Stevenson PhD Consultant Editor
July 2011
www.compoundsemiconductor.net 3
mitch.gaynor@
angelbc.com sharon.cowley@
angelbc.com shehzad.munshi@
angelbc.com robin.halder@angelbc.com jackie.cannon@
angelbc.com
Dilute nitrides: material for making money?
E:
tbrun@brunmedia.com E:
jjenkins@brunmedia.com
Dilute nitrides are the precocious siblings in the compound semiconductor family. When grown on GaAs, they have the potential to form infrared emitters and detectors that are cheaper and better than the incumbents built on the far more brittle InP platform. In addition, this slightly esoteric material can also be used to create red, orange and yellow LEDs that are less sensitive to temperature than the AlInGaP incumbents. And when these dilute nitrides are inserted into the base layer of HBTs, they can lower the transistor’s turn-on voltage.
david.ridsdale@angelbc.com
editorialview
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100 |
Page 101 |
Page 102 |
Page 103 |
Page 104