BluGlass Ltd of Silverwater, Australia says that it has succeeded in its initial laboratory experiments in developing p-type gallium nitride (p-GaN) material (essential for making up the top layers of a nitride LED).
Spun off from the III-nitride department of Macquarie University of Sydney, Australia in 2005, BluGlass developed a low-temperature process using remote-plasma chemical vapor deposition (RPCVD) to grow materials including gallium nitride (GaN) and indium gallium nitride (InGaN) on glass substrates, potentially offering cost, throughput and efficiency advantages for the production of LEDs.
The firm has now used its low-temperature RPCVD technology to create the p-GaN layer on a commercially grown metal-organic chemical vapor deposition (MOCVD) 456nm-wavelength blue multi-quantum well structure.
In preliminary testing on the sample using a 0.5mm-diameter p-type indium contact, light output was measured with a UV detector positioned under the wafer, calibrated at the wavelength of the light emission.
At a drive current of 20mA and a voltage of 4.7V, light output was 270μW (emitted at a wavelength of 458nm, with a full width half maximum of 19nm). At 50mA and 5.5V, output was 1.23mW (emitted at 456nm, with a full width half maximum of 18nm)? - the current was applied continuously for over an hour without any loss of function of the device.
At its recent annual general meeting (AGM) of shareholders, BluGlass outlined that it was looking to demonstrate p-GaN and identified a number of steps in order to demonstrate improved LED efficiency with a low-temperature process. "While these results are preliminary, they represent highly encouraging progress, ahead of our expectations towards our next major milestone to prove that a low-temperature technology can improve the efficiency of an LED," says CEO Giles Bourne.
BluGlass receives $2.3m R&D tax credit
Further to its announcement on 17 April confirming its eligibility to receive a rebate on R&D activities in 2012, BluGlass' subsidiary EpiBlu has received $1,626,027 tax credit from the Australian Tax Office. Parent company BluGlass has also received an additional $709,930.? Total tax rebates hence amount to $2,335,957 (before costs).
"This is a significant cash injection for BluGlass and it will greatly assist the company in the commercialization of its groundbreaking technology," comments CEO Giles Bourne.
