Nitridation of porous GaAs by an ECR ammonia plasma

Abstract

The effect of surface porosity of GaAs on the nature of growth of GaN, by use of plasma nitridation of GaAs, has been investigated. Porous GaAs samples were prepared by anodic etching of n-type (110) GaAs wafers in HCl solution. Nitridation of porous GaAs samples were carried out by using an electron-cyclotron resonance-induced ammonia plasma. The formation of mixed phases of GaN was investigated using the grazing angle x-ray diffraction method. A remarkable improvement in the intensity of photoluminescence (PL) compared with that of GaN synthesized by direct nitriding of GaAs surface has been observed. The PL intensity of nitrided porous GaAs at the temperature of 380 ˚C was found to be about two orders of magnitude higher as compared with the directly nitrided GaAs at the temperature of 500 ˚C. The changes in the morphology of nitrided porous GaAs have been investigated using both scanning electron microscopy and atomic force microscopy.

Electrodeposition of gallium in the presence of NH4Cl in an ionic liquid: hints for GaN formation

“…10 Another approach includes N 2 or NH 3 -H 2 plasma processes, which have been applied to develop III-V semiconductor materials. 11…”

Anaximander’s 'Boundless Nature'

“…67 Naddaf devotes a whole book to the Greek concept of nature, starting from the observation that it is "unanimously accepted (…) that the concept of phusis was a creation of Ionian science". 68 He hangs his argument on a discussion of the expression ἱστορία περὶ ϕύσεως (enquiry into the nature of all things), which is the title, ascribed since Plato to the investigations of the Presocratic philosophers, although Plato, hinting at Empedocles, Archelaos, Anaximenes, Diogenes, Heraclitus, and Alcmeon, does not mention Anaximander, nor his alleged principle (Plato, Phaedo 96 A 8, DK 31 A 76; cf. Suda, Lexicon alpha 1986, DK 12 A 2, TP 2 Ar 237, Gr Axr 4; Themistius, Oratio 26 317 C, DK 12 A 7, TP 2 Ar 120, Gr Axr 5).…”

Comparative study of structural and visible luminescence properties of AZO thin film deposited on GaAs and porous GaAs substrates

“…The use of porous GaAs as a substrate for the growth of epitaxial GaN layers by molecular-beam epitaxy has been reported [26]. In addition, the pre-treatment of GaAs by making it porous using electrochemical methods has been found to enhance the plasma nitridation processes, resulting in the formation of mixed phases of GaN with a remarkable improvement in PL intensity compared with GaN synthesized by direct nitriding of GaAs surface [28]. In addition, Porous GaAs has efficient light emission in the "blueeyellow" spectral range and has been shown to be perspective in optoelectronic and photovoltaic devices [29,30].…”