Energy is an indispensable part of our lives. We are challenging energy-saving novel light emitters and clean-energy generation systems at Energy Conversion Devices and Materials (ECO Devices) Laboratory at KAUST. The former is based on MOCVD technology, material science, and device technology. The latter is the nitride photocatalyst invented by Ohkawa. The development of highly-efficient InGaN-based blue LEDs was the topic of the 2014 Nobel Prize in Physics. InGaN-based green LEDs were realized after improving the quality of higher-In-content InGaN. The three primary colors in light are RGB. The current red LEDs are based on InGaP as the active region. If we realize red LEDs by InGaN, we can fabricate the monolithic RGB LEDs in a wafer. Such RGB integration will be a breakthrough for micro-LED displays that are the next generation after the OLED displays. In this seminar, the science of MOCVD, the growth of high-In-content InGaN, and the state-of-the-art InGaN-based red LEDs will be introduced.
Kazuhiro Ohkawa is a professor of Electrical and Computer Engineering, Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) division at King Abdullah University of Science and Technology (KAUST). Principle investigator of Energy Conversion Devices and Materials (ECO Devices) lab at KAUST. He is a Fellow of the Japan Society of Applied Physics. Before joining KAUST, he was a professor of Applied Physics at Tokyo University of Science in Japan, a professor (lifelong title) of Physics at the University of Bremen in Germany, and a senior research staff at Panasonic. He is interested in optical devices such as LEDs, laser diodes, and photocatalysts. He is familiar with wide-bandgap materials (III-Nitrides and II-VI compounds) and thin-film growth technologies (MOCVD and MBE). He invented the current n- & p-doping technologies for II-VI materials by Cl and nitrogen plasma, respectively. The nitrogen plasma became a standard in MBE for nitride semiconductors. He developed a simulation technology to understand nitride MOCVD. Many industries in Asia and Europe have introduced that simulation already. Nitride photocatalyst which is getting popular in the world is also his invention. He is challenging InGaN-based red LEDs for micro-LED displays now. Novel devices might change the world.