THUNDER BAY – Business Now – Meaglow Ltd. a privately held Thunder Bay based company has announced a breakthrough in understanding the compound semiconductor indium nitride.
Indium nitride (InN) when alloyed with gallium nitride forms the light emitting component that powers a >US$10billion dollar LED industry. In its own right InN is being developed as an advanced material for solar cells, high speed transistor devices and other applications, however there are still many things not properly understood about InN.
For instance, based on theory it had long been assumed that it simply wasn’t possible to produce nitrogen rich InN, so it was a surprise a few years ago when samples made at low temperatures were measured with greater than 30% excess nitrogen present. How could this be? Many researchers didn’t believe the measurements, though they were subsequently repeated by many groups.
Theory didn’t agree with experiment. How the excess nitrogen could occur remained largely unexplained until Meaglow Ltd’s Chief Scientist, Dr. K. Scott Butcher, recently published the explanation (see Applied Physics Letters 101 (2012) 011913).
“Basically the excess nitrogen is seen when forming the material at relatively low temperatures using plasma based nitrogen sources. These plasma sources provide the extra potential energy needed for nitrogen rich material to form. To a greater, or lesser, extent excess nitrogen species are probably present in most InN samples, as plasma techniques are commonly used” says Dr Butcher. “It may take some years for the research community to come to terms with this, but nitrogen rich InN is a reality, and now it’s a reality we understand.”
Nitrogen rich InN may also be important from another perspective. InN is plagued by a surface current problem which is limiting its development. However, the excess nitrogen species, previously ignored, may hold the key to solving this problem. As pointed out by Dr Butcher, these species are fairly mobile and migrate to sample surfaces. “They seem to fit the bill as a culprit for this phenomena.”
Meaglow Ltd. is officially launching a range of nitrogen rich InN wafers for sale exclusively on their website (www.meaglow.com) to further research and industry collaboration so that all parties can obtain a stronger understanding of InN, and so that the material can realize its full potential.
Meaglow Ltd. produces a new range of epitaxy equipment (migration enhanced afterglow), MBE & MOCVD accessories, and provides specialized semiconductor thin films to research institutes and industry.