MOVPE Growth and Luminescence Properties of GaAsN Alloys with Higher Nitrogen Concentrations

Abstract

Highly luminescent GaAsN alloy films have been successfully obtained with N concentrations up to 3.1% by metalorganic vapor phase epitaxy (MOVPE). The band-gap bowing parameter estimated from the photoluminescence (PL) peak energy is not constant but dependent on the N concentration; 24.0 eV for N < 1% and 17.0 eV for N > 1% at 20 K, and 22.4 eV for N < 1% and 14.5 eV for N > 1% at room temperature. From the characteristic features of the luminescence properties, the band-edge states are found to be much localized below the conduction band edge, and the emission process at low temperatures is associated with these localized states as in GaPN alloys.

Nitrogen content of GaAsN quantum wells by in situ monitoring during MOVPE growth

“…Also, the samples examined here contained a relatively large amount of nitrogen (from 2% to 5%) and the bowing parameter could be different for smaller nitrogen contents [10]. However, the result is in good agreement with previous reports [8,11,12]. Fig.…”

Photoluminescence Study on Temperature Dependence of Band Gap Energy of GaAsN Alloys

“…The sources for Ga, As, and N were trimethylgallium, arsine, and 1,1-dimethylhydrazine, respectively. Owing to the optimization of the MOVPE growth, highly luminescent samples have been successfully obtained even without post annealing [4]. The PL measurements were carried out at 10 to 300 K using an Ar ion laser (488 nm, 10 mW) as the excitation source.…”

“…It is reported that the temperature dependence of the band gap energy of GaAsN alloy is smaller than GaAs from absorption measurements [2] and is explained in terms of band anticrossing model [3]. In addition, photoluminescence measurements revealed that the emission related to localized states results in the reduction of the PL peak energy shift due to the temperature change [4]. In this study we have measured photoluminescence (PL) spectra of GaAsN alloys to examine in detail the temperature dependence of the band gap energy and the influence of localized states.…”

Growth and characterization of InAsN alloy films and quantum wells

“…Because the N incorporation generally introduces the high concentration free electrons, combined with the narrow-gap nature, the optical properties of InAsN near the bandgap are significantly affected by the Burstein-Moss (BM) effect (or band-filling effect) [1,3]. So, the bandgap narrowing with the N incorporation, which is commonly found in other III-V-N materials like GaAsN [5] and GaPN [6], is hardly observed in the bulk InAsN films. The band-filling effect is also expected in low-dimensional structures such as quantum wells (QWs).…”