Low-resistance Ohmic contacts are essential for the fabrication of electrical devices. While low contact resistance has been achieved to p -type layers or n -type layers separately, contacts are likely to degrade when both types need to be integrated into a single fabrication process, in particular when prior mesa etching is required. We present a solution to the problem, resulting in low-resistance Ohmic contacts on n -type GaN layers without post-deposition thermal anneal, while maintaining the quality of typical p -type contacts. We implement an integrated process for both, n - and p -contacts, involving an oxygen pretreatment to fabricate light emitting diodes with lower series resistance in the contacts and lower voltage drop at high current when compared to separately optimized contacts.
Effects of Meshed p-type Contact Structure on the Light Extraction Effect for Deep Ultraviolet Flip-Chip Light-Emitting Diodes