Molecular-beam epitaxial growth of GaAs and InGaAs/GaAs nanodot arrays using anodic Al2O3 nanohole array template masks

Mei, Xiangyang; Kim, D.; Ruda, Harry E.; Guo, Qi

doi:10.1063/1.1484554

Cited by 124 publications

(90 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The direct MBE growth of GaMnAs nanodots through a porous alumina deposition mask has not been successful 22 in spite of the successful growth of GaAs and AlGaAs nanodots using a deposition mask. 23,24 This is attributed to the required low growth temperature of GaMnAs ͑Ref. 25͒ at ϳ250°C, which is evidently too low to allow the Mn to migrate through the pores.…”

Section: Resultsmentioning

confidence: 99%

Magnetic properties of GaMnAs nanodot arrays fabricated using porous alumina templates

Bennett¹,

Menon²,

Heiman³

2008

Journal of Applied Physics

View full text Add to dashboard Cite

CdSe quantum dots-poly(3-hexylthiophene) nanocomposite sensors for selective chloroform vapor detection at room temperature Appl. Phys. Lett. 101, 173108 (2012) An "edge to edge" jigsaw-puzzle two-dimensional vapor-phase transport growth of high-quality large-area wurtzite-type ZnO (0001) nanohexagons Appl. Phys. Lett. 101, 173105 (2012) Ti-doped hematite nanostructures for solar water splitting with high efficiency J. Appl. Phys. 112, 084312 (2012) Near-infrared enhanced carbon nanodots by thermally assisted growth Appl. Phys. Lett. 101, 163107 (2012) Additional information on J. Appl. Phys. Ordered arrays of GaMnAs magnetic semiconductor nanodots have been fabricated using anodic porous alumina templates as etch masks. The magnetic behavior is studied for prepared arrays with 40 nm dot diameter, 15 nm dot thickness, and 80 nm periodicity. The disklike nanodots exhibit an easy axis for fields applied in the radial direction and a hard axis in the smaller direction. In the radial direction superparamagnetism is observed with a blocking temperature of 30 K. The fabrication technique is convenient for preparing nanodot arrays of compound semiconductors that cannot be formed by self-assembly techniques. © 2008 American Institute of Physics. ͓DOI: 10.1063/1.2955450͔ INTRODUCTIONAs research in nanoscale electronics and magnetics is flourishing, so is the demand for nanostructures of unique materials. Following the progress of growing twodimensional ͑2D͒ epitaxial structures, there has been significant advancement in fabricating lower-dimensional structures, namely, nanodots, nanowires, and nanotubes. Fabrication of highly ordered nanodot arrays composed of quantum dot semiconductors 1 and ferromagnetic nanoparticles 2,3 is drawing increased interest as advanced devices call for smaller nanostructured systems.1,4 Current research on the preparation of semiconducting nanodot arrays relies mainly on self-assembly during growth, such as InAs quantum dots in GaAs or postgrowth fabrication using photo lithography or electron beam lithography and etching. Another promising technique for fabricating nanodot arrays is the use of porous templates, such as anodic porous alumina. These can be used as shadow masks for direct deposition, [5][6][7] selective etching, 7-9 and preparation of imprint molds. 10,11 There are several advantages of using these mask techniques: ͑1͒ the fabrication of smaller dot sizes Ͻ10 nm, ͑2͒ the rapid manufacture of large-size arrays, and ͑3͒ the possibility of fabricating nanodot arrays made from a larger class of materials, including metals, compound semiconductors, and insulators. This report describes the fabrication and magnetic properties of GaMnAs magnetic semiconductor nanodot arrays. The fabrication process uses anodic porous alumina as deposition masks followed by plasma etching. A thin film of the ferromagnetic semiconductor GaMnAs is first deposited on a GaAs substrate. This is followed by the deposition of metal nanodots on the film surface using porous alumina as a mask. A ke...

show abstract

Section: Resultsmentioning

confidence: 99%

Magnetic properties of GaMnAs nanodot arrays fabricated using porous alumina templates

Bennett¹,

Menon²,

Heiman³

2008

Journal of Applied Physics

View full text Add to dashboard Cite

show abstract

“…These results should provide an effective way for controlling Dirac fermions in artificial crystal structure. Experimentally, the fabrication of periodic semiconductor QDs array have been realized by several methods, [19][20][21][22] such as self-organized anisotropic strain engineering method and the molecular-beam epitaxy using selected area growth, and so on. The lattice period as well as the unit cell structure could be tunable by regulating the lattice using lithography.…”

Section: Resultsmentioning

confidence: 99%

Generating and moving Dirac points in a two-dimensional deformed honeycomb lattice arrayed by coupled semiconductor quantum dots

et al. 2015

View full text Add to dashboard Cite

Analysis of the electronic properties of a two-dimensional (2D) deformed honeycomb structure arrayed by semiconductor quantum dots (QDs) is conducted theoretically by using tight-binding method in the present paper. Through the compressive or tensile deformation of the honeycomb lattice, the variation of energy spectrum has been explored. We show that, the massless Dirac fermions are generated in this adjustable system and the positions of the Dirac cones as well as slope of the linear dispersions could be manipulated. Furthermore, a clear linear correspondence between the distance of movement d (the distance from the Dirac points to the Brillouin zone corners) and the tunable bond angle α of the lattice are found in this artificial planar QD structure. These results provide the theoretical basis for manipulating Dirac fermions and should be very helpful for the fabrication and application of high-mobility semiconductor QD devices.

show abstract

“…The other sort of approach relies on nanoscale selective area epitaxy (NSAE) on a prepatterned substrate or growth template. The nanopatterning of substrates/templates can be realized by a variety of lithographic or nonlithographic techniques, such as interference lithography, [13,14] anodic oxidation of aluminum to form nanoporous alumina, [15][16][17][18] nanosphere lithography, [19] focused ion beam sputtering, [20] and electron-beam lithography (EBL). [21][22][23][24] At present, state-of-the-art EBL allows the creation of patterns with versatile physical geometry and localization, and homogeneous, tunable size.…”

mentioning

confidence: 99%

Growth and Optical Properties of Highly Uniform and Periodic InGaN Nanostructures

Chen

Chua

et al. 2007

Advanced Materials

View full text Add to dashboard Cite

Low-dimensional semiconductor structures, such as quantum dots (QDs), give rise to new physical phenomena that have been applied in optoelectronic and electronic devices, for example, QD laser diodes [1] and single-electron transistors. [2] To date, the formation of semiconductor dots on the nanometerscale is mostly controlled by the Stranski-Krastanow (S-K) growth mode, [3] where the self-organized formation of nanoislands is driven by the strain energy in large-lattice-mismatch systems. An alternative technique to form semiconductor QDs is by droplet expitaxy, which relies on the self-assembly of liquid metal nanoparticles of group III atoms and their crystallization into III-V semiconductor QDs by a subsequent supply of group V atoms. [4][5][6] In the self-organized processes described above, random distribution of the QD sizes and locations usually occurs, [7] which limits the benefits from low-dimensional structures. Usually, the dynamics of exciton decay are found to be monoexponential and the emission from a single dot should be very narrow. However, the disorder of the QD system governs the recombination dynamics to give a nonexponential photoluminescence (PL) decay of the entire QD ensemble.[8] Furthermore, the disorder also produces many problems in continuous wave (cw) PL experiments, in which the width of the emission spectra reflects the inhomogeneous broadening owing to the dispersion of both dot sizes and locations. One should be extremely careful when using the cw PL technique to measure unambiguously the energy and the linewidth of light emission from the QD system. [9] To obtain nanodots with homogeneous size and controlled positioning, various methods have been carried out to promote nucleation at expected sites. These methods can be divided into two categories in principle. The first is by surfacestate control, [10][11][12] such as by self-organized anisotropic strain engineering, [10] by using vertical elastic interaction in QD superlattices, [11] by ion sputtering-induced surface instability, [12] and so forth. Locally ordered nanodot arrays were produced by these methods. The other sort of approach relies on nanoscale selective area epitaxy (NSAE) on a prepatterned substrate or growth template. The nanopatterning of substrates/templates can be realized by a variety of lithographic or nonlithographic techniques, such as interference lithography, [13,14] anodic oxidation of aluminum to form nanoporous alumina, [15][16][17][18] nanosphere lithography, [19] focused ion beam sputtering, [20] and electron-beam lithography (EBL). [21][22][23][24] At present, state-of-the-art EBL allows the creation of patterns with versatile physical geometry and localization, and homogeneous, tunable size. Rigorously aligned InAs/GaAs nanodot arrays with a standard deviation of less than 5 % for both dot diameter and height were achieved by molecular beam epitaxy (MBE) on an EBL-patterned GaAs substrate.[23] Well-resolved excited states of the homogeneous QDs were observed by power-dependent PL measurements. [24]...

show abstract

Molecular-beam epitaxial growth of GaAs and InGaAs/GaAs nanodot arrays using anodic Al2O3 nanohole array template masks

Cited by 124 publications

References 11 publications

Magnetic properties of GaMnAs nanodot arrays fabricated using porous alumina templates

Magnetic properties of GaMnAs nanodot arrays fabricated using porous alumina templates

Generating and moving Dirac points in a two-dimensional deformed honeycomb lattice arrayed by coupled semiconductor quantum dots

Growth and Optical Properties of Highly Uniform and Periodic InGaN Nanostructures

Contact Info

Product

Resources

About