Luminus Devices cashes in on big chips
Even as Luminus Devices strives to ramp manufacturing to satisfy the surprise popularity of its initial lighting-class LEDs, it has launched two additional products in the range.
The market response to the high brightnesses that Luminus Phlatlight lamps produce from large GaN die has been literally overwhelming.
“The volume is actually higher than we can even fulfill right now,” Alexei Erchak, Luminus Devices founder and chief technology officer told compoundsemiconductor.net. “We are getting a response to these products that exceeds what we could have possibly imagined.”
Erchak says that Luminus capacity-build in response to this demand will be complete in the third quarter of 2009. The ramp will include its epiwafer suppliers, plus chip processing and packaging at its Massachusetts facilities and overseas contract manufacturers.
The initial demand comes from the first two white LEDs that Luminus launched in February, each using a single 3 mm x 3 mm die and producing 1000 lm at 10 W.
At the Lightfair show last week in New York, Luminus added the CSM-360-W LED that contains four such die, and can reach 60,000 lumens output.
This brightness level opens the way for solid-state lighting to be used for lighting broad areas, like warehouses, gymnasiums, theaters and even rock concerts. Before this, deploying LEDs in such high-intensity lighting would have been a very complex and expensive undertaking.
“We ve accelerated the adoption of solid-state lighting,” Erchak said. “People are putting these things into fixtures, and they re saying Hey, we thought we were going to have to wait years to get this kind of performance! ”
Smaller die sizes are also now on the agenda, with Luminus SST-50-W offering a 5 mm2 GaN chip area LED that can directly replace existing surface-mount LEDs.
While using larger LED chips elevates light output, it also presents a challenge to traditional manufacturing.
A device-killing defect in one corner of a 3 mm x 3 mm square would lead to wastage of only one of nine possible 1 mm x 1 mm die. But with what Erchak calls "big chip", the whole area could be lost, although he says that his company has overcome the problem.
In February, Luminus cross-licensed its “big chip” Phlatlight technology with Japanese GaN pioneer Nichia. It return Luminus gained access to Nichia s patents, allowing it to produce white LEDs as well as the red-green-blue chipsets it already produced for projection displays.
Nichia wasn t just after the photonic lattice light extraction methods that give the Phlatlights their name, Erchak said. He explains that Luminus has also dealt with thermal, electrical and reliability problems, as well as the yield issues related to “big chip”.
“That package of technologies was really what Nichia was most interested in,” Erchak said.