BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Talks.cam//talks.cam.ac.uk//
X-WR-CALNAME:Talks.cam
BEGIN:VEVENT
SUMMARY:Lighting the Future: Next Generation LED Lighting to save Energy a
 nd Improve our Health - Professor Sir Colin Humphreys
DTSTART:20140219T210000Z
DTEND:20140219T220000Z
UID:TALK49953@talks.cam.ac.uk
CONTACT:Graham Edgecombe
DESCRIPTION:Solid-state lighting using GaN-based LEDs could reduce the glo
 bal amount of electricity used for lighting by 50%. Lighting would then us
 e 10% of all electricity instead of the current 20%. In the UK this would 
 save £2 billion per annum in electricity costs\, and save 10% of carbon e
 missions from our power stations. The main factor preventing the widesprea
 d use of LED lighting in our homes and offices is cost. The reason why GaN
  LEDs are relatively expensive (a 40 Watt equivalent replacement LED bulb 
 costs about £15) is that they are grown on low-diameter sapphire or SiC s
 ubstrates. The Cambridge GaN group has pioneered the growth of GaN LEDs on
  6-inch Si substrates\, which will substantially reduce the cost. The grow
 th is difficult because of the large difference in thermal expansion coeff
 icients (54%) of GaN and Si\, and the large lattice mismatch (17%). This t
 alk will describe how these difficulties have been overcome. A patent has 
 been filed and two spin-off companies set up. Plessey acquired these in 20
 12 and is now manufacturing GaN LEDs on 6-inch Si at its factory in Plymou
 th\, Devon. These are the world’s first commercially available LEDs on 6
 -inch Si (and the first LEDs to be manufactured in the UK).\n\nThis talk w
 ill also describe how LEDs can be used to optimise cancer therapy\, improv
 e our health and productivity\, and even to replace WiFi.
LOCATION:Nihon Room\, Pembroke College
END:VEVENT
END:VCALENDAR