Vertical-Injection GaN-Based Light-Emitting Diodes Fabricated With Schottky-Contact Current Blocking Layer

Vertical-injection GaN-based light-emitting diodes (LEDs) fabricated with a Schottky-contact current blocking layer (ScCBL) are reported. The Ar plasma treatment to the heavily Mg-doped p-GaN led to excellent rectifying Schottky behavior, which was found to occur as a result of the suppressed hopping conduction at the contact/p-GaN interface. This could be due to the preferential removal of the Mg dopants by the Ar plasma treatment, as verified by secondary ion mass spectroscopy. Compared with the reference LEDs fabricated with SiO₂ CBL, the LEDs fabricated with ScCBL showed an identifying current-voltage curve, while the output power increased 5%, indicating that the ScCBL fabricated with the Ar plasma treatment could be used practically to improve process yields and lower the cost of vertical LEDs.