Strain-free InGaN lights up in blue, green, and red
Categorie(s) : News, Research
Published : 2 October 2018
Imagine if a single material—indium gallium nitride—could be used to fabricate blue, green, or red micro LEDs. Leti, Soitec, and equipment manufacturer Corial recently joined forces under the French Single Interministerial Fund project Butterfly to make this a reality. The partners hope to develop a 10-micron micro LED technology for augmented reality, pico-projectors, and heads-up automotive displays. At first glance, InGaN does not appear to be compatible with producing the three colors. To do so would require increasing the amount of indium, which would create excessive mechanical strain in the material. However, putting the InGaN on an oxide-sapphire substrate using a proven Soitec process relaxes the strain. Now, the researchers must tackle the challenges inherent to epitaxying a new 100% InGaN LED structure and miniaturizing the LEDs.