Researchers at NTT announced a breakthrough in the development of GaN-based thin-film devices from substrates, where an extremely thin layer of boron nitride (BN) is grown between a sapphire substrate and the GaN-based semiconductor and works as a release layer.
The newly developed MeTRe (Mechanical Transfer using a Release layer) method of production facilitates the transfer of the resulting nitride structures (typically a few μm thick) to more flexible and affordable substrates.
So far, the researchers have demonstrated a very thin LED, in which a detached thin-film device is sandwiched by two laminate films (total thickness is as small as 0.2 mm, Fig. 5 ), indicating that this technology has opened a door for GaN-based flexible devices.
NTT said this innovation helps in the production of very thin LEDs, transparent solar cells sensitive only to UV light, and highly-functional hybrid CMOS devices.
http://www.ntt.co.jp