Violet-blue GaN homojunction light emitting diodes with rapid thermal annealed p-type layers

Abstract

In this letter we report the fabrication and optical-electrical characterization of violet-blue GaN homojunction light emitting diodes. Rapid thermal annealing at 1150 °C (for 30 s) was used to activate the p-dopant species (Mg), which resulted in p-type GaN whose photoluminescence response centered around 438 nm is much stronger than that obtained from material annealed in the growth chamber at lower temperatures (700–800 °C) and a longer time (20 min).

Suppression of Spiral Growth in Molecular Beam Epitaxy of GaN on Vicinal 6H-SiC(0001)

“…Most GaN based devices are grown heteroepitaxially on SiC or sapphire by metal organic chemical vapor deposition (MOCVD) or plasma-assisted molecular beam epitaxy (MBE). Due to mismatch in lattice constants and thermal coefficients, the GaN films contain defects (mainly threading dislocations) with density as high as 1 Â 10 12 cm --2 [2,3]. During growth, these dislocations emerge at the film surface, creating spiral mounts and rough surface morphology [4].…”

Observation of 430 nm electroluminescence from ZnO/GaN heterojunction light-emitting diodes

“…This is typical of Mg-doped GaN films, and is generally attributed to transitions from the conduction band or shallow donors to deep Mg acceptor levels. 13,14 The I -V characteristics of the fabricated heterostructure at RT are presented in Fig. 3.…”

Optoelectronic characteristics of UV photodetector based on GaN/ZnO nanorods p-i-n heterostructures

“…In addition, the peak at ~450 nm may be attributed to the transitions from the conduction band or shallow donors to Mg-related acceptors in p-GaN. [23,24] The appearance of the PL spectra of p-GaN also indicates that the pumping laser beam can penetrate through the ZnO NRs into the underlying p-GaN layer. Figure 4 plots the current-voltage (I-V) characteristics of the fabricated ZnO NRs/ZnO films/p-GaN heterojunction photodetectors measured in the dark and under UV (365 nm) illumination by changing the bias voltage from −6 V to +6 V. Fig.…”