Highly Reflective Nonalloyed Ni/Ag/Pt Contact to Mg-Si Codoped p-GaN for Enhanced Efficiency of Light-Emitting Diodes

作者：Oh Munsik; Kim Hyunsoo^*

来源：Journal of Nanoscience and Nanotechnology, 2015, 15(10): 7531-7536.

DOI：10.1166/jnn.2015.11152

• Ni/Ag/Pt
• Nonalloyed Contact
• Mg-Si Codoping
• Light-Emitting Diodes

The authors report enhanced efficiency of GaN-based light-emitting diodes (LEDs) fabricated with highly reflective nonalloyed Ni/Ag/Pt contact. The Ni/Ag/Pt contact formed on the Mg-Si codoped p-GaN produced the low specific contact resistance of 7.9 x 10(-4) Omega cm(2) under as-deposited condition, which is comparable to the reference reflector (annealed at 500 degrees C for 1 min in oxygen ambient). Current-voltage-temperature measurements and the secondary ion mass spectroscopy revealed that the ohmic mechanism of the nonalloyed Ni/Ag/Pt contact is due to the more generated deep-level states associated with Mg-Si codoping, which act as the efficient hopping centers for the carrier transport at the contact/p-GaN interface. Due to the absence of interfacial reaction, the nonalloyed Ni/Ag/Pt contact showed much higher optical reflectivity (93.4% at 450 nm) as compared to the annealed sample (57.7%), resulting in a 40.5% brighter light output power as compared to the reference LEDs.

• 出版日期2015-10