Reduction of reverse‐bias leakage current in GaN‐based Schottky‐type light‐emitting diodes by surface modification using the aluminum facepack technique

Abstract

We investigated the reduction of the large reverse‐bias leakage current in GaN‐based Schottky diodes using the aluminum facepack technique, which involves the evaporation of aluminum onto the nitride surface, the subsequent oxidation of the Al film in air, and its removal by a wet‐etching technique. The reduction of the reverse‐bias leakage current was due to the mask effect of the facepack, which reduced the number of dislocation‐related leakage current paths. This reduction leads to the enhancement of quantum efficiency in Schottky‐type light‐emitting diodes (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Optical characterizations and reverse-bias electroluminescence observation for reliability investigations of the InGaN light emitting diode

“…In addition, gallium is complementary to the two gold electrodes in the LED chip and the border between the two elements (the chip area and the electrode area) is easily identifiable. By comparing the EL images, surface-temperature profile and XRF element distribution, a reversebias emission emits from the border, or the contact of the central chip area where high electric field may occur due to weak structures or structural defects [15][16][17][18][19]. This area is vulnerable to metal migration [7,20] at the border of metal contact.…”

Fabrication of Red, Green, and Blue Pixels Using Integrated GaN-Based Schottky-Type Light-Emitting Diodes

“…Hexagonal GaN layers grown on (0001) sapphire substrates with AlN buffers by conventional rf-generated plasmaassisted molecular beam epitaxy (rf-MBE) 8,9) were used for the device fabrication. The thickness of the layers, which were Si-doped layers and had an electron concentration of $1 Â 10 18 cm À3 , was 1 m. The facepack technique (FP) 7) was adopted to modify the surfaces of the layers for the formation of Schottky contacts. Detailed conditions were given in Ref.…”

“…It was reported that the surface modification is effective for improving the diode characteristics including the reduction in reverse-bias leakage current. 7) Moreover, the modification improves the quantum efficiency of the ST-LEDs. 7) The ideality factor is also improved by the modification.…”

“…7) Moreover, the modification improves the quantum efficiency of the ST-LEDs. 7) The ideality factor is also improved by the modification. RGB pixels were also fabricated using the ST-LEDs.…”

High efficiency single Ag nanowire/p-GaN substrate Schottky junction-based ultraviolet light emitting diodes

“…5,8 On the other hand, ST-LED is cost-effective due to its simplistic materials and design requirement. 9,10 Nevertheless, the tradeoff is that the metal layer also absorbs a significant percentage of the LED output, resulting in severe deterioration of the device performance. Here, we propose an ST-LED based on a single Ag nanowire (NW)/p-GaN substrate Schottky junction.…”