Effects of pre-annealed ITO film on the electrical characteristics of high-reflectance Ni/Ag/Ni/Au contacts to p-type GaN

GaN-based flip-chip LEDs with highly reflective ITO/DBR p-type and via hole-based n-type contacts for enhanced current spreading and light extraction

“…These well-known current-induced and temperature-induced efficiency droop have hindered further enhancement in LEDs performance [11,12]. Flip-chip technology was brought up as practical approach to satisfy heat dissipating [13][14][15]. In the flip-chip approach, the top-emitting LED chip is physically flipped upside down and makes contact with the submount by arrays of solder bumps, thus providing a thermal path for the generated device heat to efficiently dissipate from contacting solders to the underlying heat sink [16,17].…”

Oblique-Angle Deposited SiO2/Al Omnidirectional Reflector for Enhancing the Performance of AlGaN-Based Ultraviolet Light-Emitting Diode

“…For p-ohmic contact, Ni/Ag/Ni (1 nm/52 nm/10 nm) was deposited on the p-AlGaN with an e-beam evaporator. 26 The mesh-shaped Ni/Ag/Ni layers with two different widths (2.5 and 5 μm) were used and the ratio of the ODR to metal mesh area varied from 0% to 60%. After annealing the Ni/Ag/Ni layer for 1 min at 500 °C in air to produce an ohmic contact, an Al (200 nm)/Ni (20 nm) p-reflective pad and Cr (5 nm)/Al (200 nm)/Ni (50 nm) n-pad layers were deposited by e-beam evaporation.…”