In the 1960s, the first light-emitting LED diodes were developed. The red LED was first created by Nick Holonyak in 1962. Years later, in 1967, Georde Craford created the first green LED. But, what not many people know is that it was not until 1993 when, after much insistence, Shuji Nakamura created the first blue LED diode.
Nowadays you can go to any electronics store (or online) and buy blue LEDs without problems. Creating them was not easy, since it took a lot of effort to find a suitable material that could emit blue light.
The difficulty is that the waveform of blue light is shorter than that of red or green. A material was required that was in the “bandgap” so that it could generate this blue light. The problem is that for decades the existence of an optimal material was unknown, until Shuji Nakamura found it.
Creating a blue LED, an odyssey that lasted decades
Initially, light-emitting LED diodes were only used in signaling devices. Since green and red existed, they were commonly used to show whether an electronic device was on or off. A set of these could be used to display a complex state, such as in music players, to display frequency oscillation.
You should know that in the 1980s gallium nitride (GaN) was discovered and it had the property of generating blue light. But I had a pretty big problem and that is that synthesizing and manipulating this material was very complicated. It used to have defects that affected efficiency.
It was not until 1993 when Shuji Nakamura of Nichia Corp managed to synthesize the first blue LED made of Indium Gallium Nitride (InGaN). At the same time, Isamu Akasaki and Hiroshi Amano were working on the crystalline nucleation of gallium nitride on sapphire substrates to obtain p-type doping.
We have to highlight that GaN had already been investigated previously on multiple occasions. It was known that it had emission capacity in the blue light band, but due to its complex crystallization process, it was discarded until Shuji arrived.
Shuji Nakamura did not have a doctorate and this made many of his classmates despise him. Since he was not allowed to use the machinery for his research, he tried to replicate it, something that led him to be considered by his colleagues as more of a simple technician.
But, thanks to his determination and insistence, he managed to develop the first blue LED diode. With this development and the red and green LEDs, white light could now be created. Not only did it generate a revolution in the lighting industry, it was the beginning of the creation of high-resolution LED and LCD screens.
Thanks to this development, we can indeed have gaming monitors, laptop screens, SmartTV, smartphones, tablets, screens in cars, etc. If it weren’t for Nakamura’s insistence, we probably wouldn’t have all these devices today.
Two decades later, in 2014, both Nakamura, Akasaki and Amano received the Nobel Prize in Physics. His work for the development of the blue LED and his contribution to humanity was thus recognized.
