The development of metal buffer layers and chemical lift-off process can supply GaN template substrates and new process for high brightness LEDs, and results in low cost process which give strong impacts on optical and electronic devices. Instead of conventional low-temperature buffer layers, We succeed in growing high crystallinity GaN by inserting metal buffer layers in between sapphire substrates and GaN epitaxial layers, which enable to chemically lift-off LED structures from the sapphire substrates by selective etching of metal buffer layers. Such novel device processes will contribute to realizing novel and various lighting devices based on high-brightness LEDs. The result was reported in the newspapers of Nikkan-Kogyo, Kahoku-Shimpo (on Apr. 7) and Ashahi (on Apr. 8), and broadcast by NHK.
Fig. Blue light emission from an LED fabricated on a metal buffer deposited on sapphire. The performance of the LED is superior to that of conventional LEDs.