This diode is an early version of the blue-light-emitting diode (LED) developed by Isamu Akasaki in 1978. It is a MIS (metal-insulator-semiconductor) LED and was the brightest until then. In the 1980s, working with Hiroshi Amano, Akasaki did further research on gallium nitride crystals, which eventually led to blue diodes that could be combined with red and green ones to make white light.
Isamu Akasaki donated the LED to the Nobel Prize Museum in 2014.
Graphite, one of the forms in which pure carbon occurs, has played a part in many vital experiments. Together with his mentor, Isamu Akasaki, Hiroshi Amano worked doggedly to produce extremely pure crystals of gallium nitride. He used these pieces of graphite as a base and applied a layer of sapphire, followed by layers of gallium nitride.
Hiroshi Amano donated the graphite to the Nobel Prize Museum in 2014.
