AlGaN/AlGaN double-heterojunction ultraviolet light-emitting diodes grown by metal organic chemical vapour deposition

Light emitting diodes using an AlxGa1-xN/AlyGa1-yN double-heterojunction have been demonstrated with an ultraviolet emission peak at lambda = 321 nm with a linewidth of 7.7 nm. The devices were grown by metal organic chemical vapour deposition on c-plane sapphire substrates. The active region is composed of a single laver of AlxGa1-xN (x = 0.23) and the cladding layers are p-type and n-type AlyGa1-yN (y = 0.45). The fight output from the diodes was measured through the sapphire substrate in a 'p-side down' configuration. At a current of 35 mA DC, an output power of similar to 39 nW was measured without any coatings on the device.