Tag: gallium nitride

Gallium nitride semiconductors can withstand high voltage

Scientists have developed a method which allows gallium nitride (GaN) to be practically implemented to allow high-powered and energy efficient devices in the future, allowing 10 times as much power to flow through the material.

In order to produce future renewable technologies such as smart grids or electric cars it is necessary to develop need high-power semiconductor devices, and gallium nitride offers a much more efficient energy usage than current technologies, say the researchers.

However while gallium nitride hold many properties that lends itself to such usages, it is unable to withstand large voltages that are necessary in certain functions

“Power-handling capacity is important for the development of those devices,” said Merve Ozbek, a researcher at North Carolina State University.

Research previously undertaken into the use of high power GaN devices has encountered problems due to large electric fields being created at specific points located at the edge of devices, when high voltage currents were applied, effectively frying the device.

However the researchers at NC have looked toward solving this problem by implanting a buffer made of argon around the edges that can handle around 10 times as much power pulsing through it.

This buffer then works by spreading out the electric field away from just small areas, thus avoiding the destruction of the device.

When testing the new method on common electronic components known as Schottky diodes, it was shown that the argon implant allowed the breaking point to be raised from 250 volts without to 1,650 with the added material.

“By improving the breakdown voltage from 250 volts to 1,650 volts, we can reduce the electrical resistance of these devices a hundredfold,” says Dr. Jay Baliga, a professor at NC State and co-author of the paper. “That reduction in resistance means that these devices can handle ten times as much power.”

Mitsubishi makes breakthrough on cheap LED substrates

The man who invented the blue LED has joined forces with Mitsubishi Chemical and developed a way of producing much cheaper LED substrates.

According to Japanese wire Nikkei.com, Shuji Nakamura and scientists at Mitsubishi have developed a technique that allows them to grow gallium nitride (GaN) crystals as large as two inches in diameter.

When the crystals are sliced, they can be used to make LEDs with far lower power consumption and provide three times the power of those made from sapphire substrates.

Making GaN crystals is expensive but by 2012, said the report, Mitsubishi will be able to go into mass production of two inch substrates as early as 2012. There’s more here (subscription needed).