Effects of different plasma species (atomic N, metastable N2*, and ions) on the optical properties of dilute nitride materials grown by plasma-assisted molecular-beam epitaxy

Abstract

Articles you may be interested inInternal quantum efficiency of III-nitride quantum dot superlattices grown by plasma-assisted molecular-beam epitaxy Role of ionized nitrogen species in the optical and structural properties of GaInNAs/GaAs quantum wells grown by plasma-assisted molecular beam epitaxy

Effect of low nitrogen concentrations on the electronic properties ofInAs1−xNx

“…This setting was precisely precalibrated to give efficient dissociation of N 2 into atomic nitrogen and to keep a low density of ionized molecular species, which are known to degrade the crystal quality. 24 The N content ͑x =1%, 0.6%, 0.4%, 0.2%, and 0%͒ in each epilayer was controlled by setting the growth temperature, T G , and the growth rate, r G , to given values in the ranges T G = 400-460°C and r G = 0.3-1 m / h, and by keeping a minimum As flux. Our control sample, i.e., an InAs epilayer, was grown at T G = 460°C.…”

“…26 These states may arise from crystal defects caused by the nitrogen plasma and the low-growth temperature. 24,25 In the next section, we use cyclotron resonance experiments to investigate further the effect of the nitrogen and of composition disorder on the electronic properties.…”

Molecular Beam Epitaxy of Nitrides for Advanced Electronic Materials

“…Despite the fact that ionized molecules (N 2 þ ) and ionized atoms (N þ ) are still present in an rf source, their concentrations are much smaller and the predominant species are made up mainly by neutral atoms (N) and excited neutral molecules (N 2 *) [36,44]. The common notion is that neutral atomic N and metastable molecules represent the major reactive species [45,47,48] participating in the growth of nitrides by PAMBE, though there are contradictory conclusions in the literature as to which of these two, if either, is predominant. The common notion is that neutral atomic N and metastable molecules represent the major reactive species [45,47,48] participating in the growth of nitrides by PAMBE, though there are contradictory conclusions in the literature as to which of these two, if either, is predominant.…”

“…This was also confirmed by correlated OES and growth studies by Kikuchi et al [49], further showing that not only molecular N 2 * but also its long-lived metastable state A 3 S u þ contributed strongly to the growth. For instance, high rf power and low gas flow tend to produce larger atomic N content, but also more ionized nitrogen (N þ , N 2 þ ) [48,49]. Another factor to consider is that conditions used for generating high amounts of neutral atomic N may also lead to higher ion fluxes.…”

Growth and characterization of GaInNAs by molecular beam epitaxy using a nitrogen irradiation method

“…However, the optical quality of GaInNAs deteriorates significantly with increasing N mole fraction due to the plasmainduced damage and the low solubility of nitrogen in the GaAs matrix. A low-growth rate with a low-radio frequency (RF) power [3] or an N-plasma source with an optimized DC bias [8] is often used in order to effectively incorporate N without deterioration of the material quality. Still, it is difficult to obtain efficient lasing at 1.55 mm unless GaNAs barriers are used or Sb is incorporated in the QW.…”