Properties of low-pressure chemical vapor epitaxial GaN films grown using hydrazoic acid (HN3)

Abstract

We have grown high-quality GaN films on sapphire using a new nitrogen precursor, hydrazoic acid ͑HN 3 ͒. Films were grown at 600°C on ͑0001͒ sapphire substrates in a low-pressure chemical-vapor-deposition system using triethylgallium and hydrazoic acid as precursors. Subsequently, we have conducted a complete study of the surface, structural, electrical, and optical properties of these GaN films, and our early results are very encouraging. All films were of wurtzite crystal structure, slightly polycrystalline, and n type at about 2ϫ10 17 cm Ϫ3 . We find the films to be efficient light emitters in the near-band edge region of the spectrum. Analysis of the emission energies and kinetics suggests that the midgap emission results from a superimposed deep-donor-to-shallow-acceptor emission and a deep-donor-to-valence-band emission, where the deep donor consists of a distribution of energy levels, thereby yielding a broad emission band.

Effect of annealing on photoluminescence properties of neon implanted GaN

“…The 3.44 eV peak appearing after annealing in the scans of highly implanted samples in previous measurements of annealing at 800 be present in post annealing scans of all implanted samples. This peak is identified as an oxygen related peak which is due to the radiative recombination of an electron on the oxygen donor level and a hole in the valance band [12,13]. The 3.36 eV line appears in the post-annealing scans of all implanted samples and the 3.37 eV line is only present in the scans of implanted samples with doses higher than 2 × 10 15 cm −2 .…”

Effect of isochronal annealing on photoluminescence properties of Mn-implanted GaN

“…The peak at 3.42-3.44 eV is attributed in literature to the oxygen impurity in GaN samples [21,22]. The emergence of oxygen-related peak at 3.44 eV as well as suppression of BL band gives a strong clue that the V Ga O N complexes have broken, thereby releasing oxygen.…”

Materials Chemistry of Group 13 Nitrides

“…Less dangerous alkyl derivatives of hydrazine, such as (CH 3 ) 2 N -NH 2 , have also been studied, but again gave unwanted carbon impurities at 550-650 • C and a V/III ratio of 160 : 1 [69][70][71]. Using hydrogen azide HN 3 , which is an even more dangerous compound [72], very good nitride films were grown at low temperatures using either OMVPE or MBE techniques [73]. A study on nitrogen precursors including NH 3 , N 2 H 4 , and NEt 3 showed that, whatever the N precursor is, thermal decomposition does not produce significant amounts of the active species N, NH or NH 2 , and a large excess of the N source is still needed [74].…”