More efficient, high-brightness MicroLED developed by Nagoya University, Japan

Researchers at Nagoya University in Japan have investigated a way to make LEDs brighter while maintaining their efficiency. This study promises to reduce the cost of LED production and its impact on the environment, while improving its performance in applications such as visible light communication and virtual reality (VR) glasses. The findings were published in the journal Laser & Photonics Review as “How to Make Semi-Polar InGaN Light Emitting Diodes with High Internal Quantum Efficiency: The importance of the Internal Field.”

Indium gallium nitride LEDs are considered one of the most efficient light sources, but they generally only operate at low power levels. In order to obtain higher brightness light, its power needs to be increased. However, adding more power to the led causes its efficiency to decrease, a phenomenon known as efficiency decline.

One way to overcome the efficiency slippage is to increase the area of the led to improve the light output, but this also requires the use of a larger chip. However, as the chip size increases, the number of LEDs that the wafer can produce will decrease, resulting in higherproduction costs and greater environmental impact.

In response, the researchers changed the polarization characteristics of the resulting crystal by tilting the InGaN layer and cutting the wafer in different directions, thereby reducing the led efficiency slippage. Researchers have fabricated (1013) -directional LEDs on an inexpensive sapphire substrate that perform better at higher power.

This discovery provides innovative ways for manufacturers to develop next-generation led technologies, such as the development of more efficient and brighter Micro LED displays for mobile devices and large-screen TVs; the development of higher current density LEDs for automotive and specialty industrial lighting applications; and the development of faster switching speed LEDs for use in visible light communication technology and VR glasses.

Researchers say future studies are likely to fail to find better cutting directions than this, especially on sapphire substrates.