Plessey fabricates GaN on Si LEDs


Thin GaN layer requires less deposition time; yields high throughput and lower costs


Plessey Semiconductors, one of the first companies to make working GaN on Si LEDs, where first samples produced the correct wavelength output from its 6-inch IC production line, has taken delivery of an Aixtron CRIUSE II-XL reactor in a 7x6-inch wafer configuration. The multi-million pound investment creates a production line for new HBLED (High Brightness LED) products. These will use Plessey's MaGIC (Manufactured on GaN IC) technology of GaN on 6-inch silicon substrates. Manufacturing at its Plymouth facility creates new high tech manufacturing jobs for the UK. Neil Harper, Plessey's HBLED Product Line director explains "We use a much thinner GaN layer at only 2.5μm compared to 6-8μm in other GaN on Si technologies. This means less deposition time, so that we can do multiple production cycles in the reactor in 24 hours to achieve higher throughputs and lower costs." Plessey uses standard, readily available 6-inch silicon substrate, offering in the order of 80% cost reduction compared to current technologies using SiC (Silicon Carbide) or Sapphire, both expensive and hard to scale up. In future Plessey intends to move to 8-inch substrates for even greater cost savings. Efficiencies in the new technology will enable outputs in excess of 150 lumens per watt to be achieved, significantly brighter than anything commercially available. Typical MAGIC HB LEDs are yielding at 95% providing over 14,000 1 sq. mm 1 Watt MAGIC HB LEDs per 6-inch wafer. Barry Dennington, Plessey's COO, noted, "MaGIC and EPIC are two unique, disruptive technologies that are instrumental in our plan to rapidly grow Plessey into a major electronics company producing smart lighting solutions." Plessey Semiconductors