AlGaAs/GaAs/AlGaAs quantum wells as a sensitive tool for the MOVPE reactor environment

Dimastrodonato, V.; Mereni, L.; Young, Robert J.; Pelucchi, E.

doi:10.1016/j.jcrysgro.2010.07.021

Cited by 42 publications

(36 citation statements)

References 34 publications

(54 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…18 The growth pressure was 80 millibars, the V/ III ratio was 220, and the wafer surface temperature was 650 C as measured by emissivity-corrected pyrometry. HfO 2 layers were deposited using tetrakis dimethylamido hafnium (TDMA-Hf) and H 2 O precursors in a Picosun # ALD reactor at 250 C, with a pulse/purge time of 0.1 s TDMA-Hf-20 s N 2 -0.1 s H 2 O-20 s N 2 and ultra-high purity N 2 as both carrier and purging gas (200 sccm).…”

Section: Methodsmentioning

confidence: 99%

Chemical and electrical characterization of the HfO2/InAlAs interface

Brennan

Galatage

Thomas

et al. 2013

Journal of Applied Physics

Self Cite

View full text Add to dashboard Cite

InAlAs has the potential to be used as a barrier layer in buried channel quantum well field effect transistor devices due to favorable lattice-matching and carrier confinement properties with InGaAs. Field effect device structures of this nature may also require a high-k oxide deposited on the InAlAs surface to reduce leakage current. This study investigates the impact of surface preparations and atomic layer deposition of HfO2 on these surfaces using x-ray photoelectron spectroscopy to analyse the chemical interactions taking place, as well as the electrical performance of associated capacitor devices. A large concentration of As related surface features is observed at the InAlAs surface, and is attributed to a large D-it response in electrical measurements. (C) 2013 AIP Publishing LLC

show abstract

Section: Methodsmentioning

confidence: 99%

Chemical and electrical characterization of the HfO2/InAlAs interface

Brennan

Galatage

Thomas

et al. 2013

Journal of Applied Physics

Self Cite

View full text Add to dashboard Cite

show abstract

“…The structures, all capped with a GaAs layer, were grown on (001) GaAs perfectly oriented or slightly misoriented substrates. 17 The precursors were trimethylgallium (TMGa), trimethyaluminum (TMAI), trimethylindium (TMI), and arsine (AsH 3 ) or tertiarybutylarsine (TBA). Growth conditions and structural design varied from sample to sample; relevant details are referenced in the text when a particular example is discussed.…”

Section: Methodsmentioning

confidence: 99%

Wettability and “petal effect” of GaAs native oxides

Gocalinska¹,

Gradkowski²,

Dimastrodonato³

et al. 2011

Journal of Applied Physics

Self Cite

View full text Add to dashboard Cite

We discuss unreported transitions of oxidised GaAs surfaces between (super)hydrophilic and hydrophobic states when stored in ambient conditions. Contact angles higher than 90° and high adhesive force were observed for several air-aged epitaxial samples grown under different conditions, as well as on epi-ready wafers.Regardless of the morphologies of the surface, superhydrophilicity of oxygen-plasma treated samples was observed, an effect disappearing with storage time. Reproducible hydrophobicity was likewise observed, as expected, after standard HCl surface etching.The relation between surface oxides and hydrophobic/hydrophilic behaviour is discussed.

show abstract

“…During growth, particular care is taken to monitor unintentional impurity levels. [9][10][11] The QDs are self-formed at the bottom of the inverted pyramids during deposition of the In 0.15 Ga 0.85 As layer due to capillarity effects and decomposition-rate anisotropy. 12,13 Before and after growth of the QD layer, an Al 30 Ga 70 As barrier layer was grown (see the inset of Fig.…”

Section: Samplementioning

confidence: 99%

Quantum dot asymmetry and the nature of excited hole states probed by the doubly positively charged excitonX2+

et al. 2013

Self Cite

View full text Add to dashboard Cite

In this experimental and theoretical study, it was found that the emission pattern of the doubly positively charged exciton complex X 2+ strongly depends on the nature of the involved excited hole states as well as the quantum dot symmetry. The two-hole system in the final state of the X 2+ recombination for the investigated high-symmetry pyramidal InGaAs quantum dots does not exhibit the singlet-tripletlike arrangement previously observed for the two-electron counterpart. Instead, the final states exhibit two true doublets, in accordance with group-theoretical predictions. Asymmetry is manifested in the photoluminescence spectra of X 2+ by a significant splitting of one doublet, which is a spectral feature exhibited to some degree by all of the measured quantum dots. The analysis demonstrates that an external magnetic field elevates the symmetry of the quantum dots. This work highlights the exciton complex X 2+ as a very sensitive probe of the quantum dot shape as well as the nature of the involved quantum states. Thus, its spectral features are very suitable for an efficient uninvasive postgrowth symmetry characterization of quantum dots.

show abstract

AlGaAs/GaAs/AlGaAs quantum wells as a sensitive tool for the MOVPE reactor environment

Cited by 42 publications

References 34 publications

Chemical and electrical characterization of the HfO2/InAlAs interface

Chemical and electrical characterization of the HfO2/InAlAs interface

Wettability and “petal effect” of GaAs native oxides

Quantum dot asymmetry and the nature of excited hole states probed by the doubly positively charged excitonX2+

Contact Info

Product

Resources

About