Manufacturing Method for Green LEDs Delivers Light Output for MicroLED Displays

Plessey, a developer of microLED technology for the augmented reality and display markets, has introduced a 2D planar gallium nitride on silicon (GaN-on-Si) process to emit green light without the need for color conversion techniques.

To produce green light, LED manufacturers typically apply phosphors or quantum dot conversion materials to native blue LEDs. These materials then convert short-wavelength, typically 450-nm, blue light to red or green wavelengths with 10 to 30 percent efficiency.

Plessey’s green LEDs are formed using its GaN-on-Si epitaxial growth process similar to the native blue LEDs with the principal difference coming in the amount of indium that is incorporated in the quantum well structures of the LED. With no color conversion losses, the native green emission is orders of magnitude brighter than that of color converted process for microLEDs.

With a dominant green wavelength of 530 nm and a full width half maximum wavelength of 31 nm, the green is well-suited for color displays. Additionally, the green emission exhibits outstanding wavelength stability versus current density.