Recent progress of tunnel junction-based ultra-violet light emitting diodes

Semiconductor ultra-violet light-emitting diodes for flash photolysis.

'Caged' compounds are biological molecules that are rendered inactive by a protecting (cage) group. Photocleaving of chemical bonds associated with the cage species with intense UV light results in the release of the active molecules. This technique, called flash photolysis, allows for real-time study of interacting biological molecules and typically involves the use of high intensity lasers or...

Ultra-violet light-emitting diodes with quasi acceptor-free AlGaN polarization doping

The development and application of nitride-based light-emitting diodes (LEDs) is handicapped by the low hole conductivity of Mg-doped layers. Mg-doping becomes increasingly difficult with higher Al-content of the p-AlGaN layers as required for ultraviolet (UV) light emission. Polarization-induced hole doping of graded AlGaN was recently demonstrated as an alternative doping method. Using advanc...

Recent progress and future prospects of AlGaN-based high-efficiency deep-ultraviolet light-emitting diodes

ZnO - Based Light - Emitting Diodes

Tunnel-injection GaN quantum dot ultraviolet light-emitting diodes

We demonstrate a GaN quantum dot ultraviolet light-emitting diode that uses tunnel injection of carriers through AlN barriers into the active region. The quantum dot heterostructure is grown by molecular beam epitaxy on AlN templates. The large lattice mismatch between GaN and AlN favors the formation of GaN quantum dots in the Stranski-Krastanov growth mode. Carrier injection by tunneling can ...