Optical characterization of InAsN single quantum wells grown by RF‐MBE

Kuroda, Masayuki; Katayama, Ryuji; Onabe, Kentaro; Shiraki, Y.

doi:10.1002/pssb.200405032

Cited by 9 publications

(11 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For comparison, we also show some results from absorption measurements published previously by other groups. [8][9][10] The dashed curve shows the theoretical be-…”

Section: Analysis and Discussionmentioning

confidence: 99%

“…Such effects have, indeed, proven extremely problematic in previous attempts to measure band gap reduction directly in InNAs using absorption spectroscopy, with large blueshifts being observed rather than any redshift. [6][7][8][9] The Moss-Burstein shifts were "subtracted" during analysis to infer a net redshift in band gap. [7][8][9] An unambiguous redshift of the absorption edge of InNAs alloys with increasing nitrogen content has been seen only in one previous study.…”

Section: Introductionmentioning

confidence: 99%

“…[6][7][8][9] The Moss-Burstein shifts were "subtracted" during analysis to infer a net redshift in band gap. [7][8][9] An unambiguous redshift of the absorption edge of InNAs alloys with increasing nitrogen content has been seen only in one previous study. 10 In a previous preliminary study, we used photoluminescence ͑PL͒ spectroscopy to investigate the nitrogen-induced band gap reduction in InNAs samples containing nitrogen percentages ͑N͒ of 1.0% and 2.2% at temperatures between 77 and 300 K. 4 Rather than probing the absorption edge, PL spectroscopy measures the light emitted by a recombining population of thermalized carriers.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Photoluminescence of InNAs alloys: S-shaped temperature dependence and conduction-band nonparabolicity

et al. 2007

View full text Add to dashboard Cite

Photoluminescence ͑PL͒ has been used as a means of unambiguously observing band gap reduction in InNAs epilayers grown by molecular beam epitaxy. The observed redshift in room temperature emission as a function of nitrogen concentration is in agreement with the predictions of the band anticrossing ͑BAC͒ model, as implemented with model parameters derived from tight-binding calculations. The temperature dependence of the emission from certain samples exhibits a signature non-Varshni-like behavior indicative of electron trapping in nitrogen-related localized states below the conduction-band edge, as predicted by the linear combination of isolated nitrogen states ͑LCINS͒ model. This non-Varshni-like behavior tends to grow more pronounced with increasing nitrogen content, but for the highest nitrogen concentration studied, the more familiar Varshni-like behavior is recovered. Although unexpected, this observation is found to be consistent with the BAC and LCINS models. With consideration given to the effects of conduction-band nonparabolicity on the emission line shapes, the BAC model parameters extracted from the measured PL transition energies are found to be in excellent agreement with the predictions of the aforementioned tight-binding calculations.

show abstract

“…For comparison, we also show some results from absorption measurements published previously by other groups. [8][9][10] The dashed curve shows the theoretical be-…”

Section: Analysis and Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Photoluminescence of InNAs alloys: S-shaped temperature dependence and conduction-band nonparabolicity

et al. 2007

View full text Add to dashboard Cite

show abstract

“…So, we avoided N flux in the growth of the wetting layer. For the growth of the InAsN QDs, the rf power and the N 2 flow rate were 175 W and 0.50 sccm, which gave x = 0.02 in a bulk InAs 1-x N x layer [3,4]. For reducing the N supply by half, the N 2 flow was allowed intermittently by 1-sec-duration and 50%-duty pulses.…”

Section: Methodsmentioning

confidence: 99%

“…The same thing may be expected in the QDs, giving a red-shift of emission spectra. In fact, the bandgap reduction of the InAsN alloy is estimated as ~40 meV with 1%-N incorporation [4,5]. It has also been shown that N can be incorporated into InAs up to ~5 % in spite of the extremely low equilibrium solubility [5].…”

Section: Introductionmentioning

confidence: 98%

Growth and optical characterization of InAsN quantum dots

Tsurusawa

Nishikawa

Katayama

et al. 2006

Physica Status Solidi (b)

Self Cite

View full text Add to dashboard Cite

Self-assembled InAsN quantum dots (QDs) have been grown by rf-plasma-assisted molecular beam epitaxy (RF-MBE) on GaAs(001) substrates via a 2-monolayer (ML)-thick InAs wetting layer. The InAsN QDs are typically 30 -70 nm in diameter and 3 -7 nm in height. The dot density was 3.6 × 10 9 -2.3 × 10 10 cm -2 for the fluxes corresponding to the nominal thicknesses of 3.0 -4.0 MLs. As the nominal thickness increases, the dot density increases, while the diameter decreases. The low-temperature (10 K) photoluminescence (PL) of the QD samples shows emission spectra in the wavelength range of 1.2 -1.6 µm apparently caused by the N incorporation (0.8 -2.0%) into the QDs. The QD size distribution causes broad emission spectra.

show abstract

InAsN quantum dots grown on GaAs(001) substrates by MOVPE

Kuboya

Thieu

Nakajima

et al. 2007

Phys. Status Solidi (c)

Self Cite

View full text Add to dashboard Cite

The self-assembled InAsN quantum dots (QDs) were grown on the GaAs (001) substrates by MOVPE using 1,1-dimethlhydrazine (DMHy) and tertiarybutylarsine (TBAs) as the N and As precursors, respectively. The size distribution of the InAs(N) QDs grown at 450 °C and 420 °C is found bimodal. The InAsN QDs are typically 4-11 nm in height and 30-41 nm in width. The N incorporation into InAs induces the decrease of the QDs size, due to the increase of the wetting layer thickness. The density of the InAsN QDs with a nominal source supply of 2.6-3.0 ML, increases from 1.1-1.3×1010 cm -2 for the 450 °C growth to 2.1-2.3×10 10 cm -2 for the 420 °C growth. The photoluminescence peaks (at 300 K) of the InAs(N) QDs grown at both temperatures clearly show a red-shift to 1200 nm by N incorporation. This red-shift is in contrast with the blue-shift expected from the decrease in the dot sizes (quantum size effect), indicating the huge bandgap bowing induced by N incorporation is dominant over the quantum size effect.1 Introduction The laser devices based on the quantum dots are potentially useful due to the low threshold current density and high-temperature lasing characteristics [1]. To extend the emission wavelength of the InAs quantum dots (QDs) toward 1.3 µm and 1.55 µm for optical fiber communication systems, many efforts have been devoted. As in other III-V-N type alloys such as GaAsN and GaPN, InAsN is expected to have a large bandgap bowing, which will give a significant reduction of the bandgap with N incorporation. The bandgap reduction of InAsN films, however, is hindered due to the Burstein-Moss (B-M) effect, which causes the blue-shift of the absorption edge, induced by the high electron concentration associated with the N incorporation [2][3][4][5][6]. It has already been demonstrated that the occurrence of the B-M effect could be suppressed in the quantum well structure due to the step-like functional form of the two-dimensional density of states (DOS) of quantum wells [7][8][9]. Thus, the QDs structure could also suppress the B-M effect because of their delta functional form of the DOS even in the case of a rise in residual carrier concentration, and it is expected that the N incorporation into InAs QDs will extend the emission wavelength to the longer region. For this characteristic feature, several attempts to grow the InAsN QDs have been done with metalorganic vapor phase epitaxy (MOVPE) [10] and molecular beam epitaxy (MBE) [11,12]. In this work, the InAs(N) QDs grown by MOVPE have been investigated to elucidate the effect of N incorporation on the structural and photoluminescence (PL) properties.

show abstract

Optical characterization of InAsN single quantum wells grown by RF‐MBE

Cited by 9 publications

References 7 publications

Photoluminescence of InNAs alloys: S-shaped temperature dependence and conduction-band nonparabolicity

Photoluminescence of InNAs alloys: S-shaped temperature dependence and conduction-band nonparabolicity

Growth and optical characterization of InAsN quantum dots

InAsN quantum dots grown on GaAs(001) substrates by MOVPE

Contact Info

Product

Resources

About