Efficient Blue Light-Emitting Diodes
Isamu Akasaki, Hiroshi Amano & Shuji Nakamura
About This Prize
The 2014 Nobel Prize in Physics was awarded to Isamu Akasaki, Hiroshi Amano, and Shuji Nakamura “for the invention of efficient blue light-emitting diodes which has enabled bright and energy-saving white light sources.” Red and green LEDs had existed for decades, but blue proved extraordinarily difficult. Their breakthroughs in gallium nitride (GaN) crystal growth and p-type doping in the late 1980s and early 1990s completed the color spectrum, enabling white LED lighting that is now transforming global energy consumption and illumination technology.
Shuji Nakamura
“Fascinated Journeys into Blue Light”
Hiroshi Amano
“Growth of GaN on Sapphire by Low Temperature Deposited Buffer Layer”
Isamu Akasaki
“Background Story of the Invention of Efficient Blue InGaN Light Emitting Diodes”
Key Concepts
- • Gallium Nitride (GaN) Semiconductors: Wide-bandgap III-V material (~3.4 eV) capable of emitting blue and ultraviolet light
- • p-Type Doping Breakthrough: Achieving reliable p-type conductivity in GaN through Mg doping and electron-beam activation overcame a decades-long barrier
- • Buffer Layer Technique for Crystal Growth: Low-temperature AlN and GaN buffer layers enabled high-quality epitaxial growth on sapphire substrates
- • White LED Lighting Revolution: Combining blue LEDs with phosphor coatings produces white light exceeding 150 lm/W efficiency, far surpassing incandescent and fluorescent sources