Tunnelling efficiency of n -InGaN/GaN short period superlattice tunnelling contact layer for nitride-based light emitting diodes

Nitride-based light emitting diodes (LEDs) with Si-doped n + -In 0.23 Ga 0.77 N/GaN short-period superlattice (SPS) tunnelling contact top layers have been fabricated. By using such a SPS structure, we can significantly reduce the specific contact resistance, and thus the operation voltage, of the fabricated LEDs. We have also found that the LED operation voltage is almost independent of the CP 2 Mg flow rate when we grow the underlying p-type GaN layers.