Fabrication and Luminescence of Etched Quantum Rings and Vertically Coupled Dots

1995 ◽  
Vol 406 ◽  
Author(s):  
G. E. Philippa ◽  
J. A. Mejia Galeana ◽  
C. Cassou ◽  
P. D. Wang ◽  
C. Guasch ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Electron Beam ◽  
Electric Field ◽  
Emission Spectrum ◽  
Electron Beam Lithography ◽  
Electrical Contacts ◽  
Outer Diameter ◽  
Quantum Rings ◽  
Order Of Magnitude ◽  
Linewidth Broadening

AbstractThe fabrication of GaAs-GaAIAs coupled quantum dots and of quantum rings using electron beam lithography and dry etching is described. Coupled dots of physical diameter of 500 and 250 nm were fabricated and processed with top electrical contacts to apply an electric field. We show that the emission spectrum of coupled dots is modified by the electric field. Quantum rings of 400 nm outer diameter and wall thickness of 25 nm were fabricated. The emission spectrum from rings showed the quantum well emission shifted to higher energies and although its intensity decreased by about one order of magnitude there was little linewidth broadening.

scholarly journals Universal direct patterning of colloidal quantum dots by (extreme) ultraviolet and electron beam lithography

Nanoscale ◽  
2020 ◽  
Vol 12 (20) ◽  
pp. 11306-11316
Author(s):  
Christian D. Dieleman ◽  
Weiyi Ding ◽  
Lianjia Wu ◽  
Neha Thakur ◽  
Ivan Bespalov ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Electron Beam ◽  
Electron Beam Lithography ◽  
Extreme Ultraviolet ◽  
Luminescent Properties ◽  
Colloidal Quantum Dots ◽  
Direct Patterning ◽  
One Step ◽  
Patterning Technique

A general, one-step patterning technique for colloidal quantum dots by direct optical or e-beam lithography. Photons (5.5–91.9 eV) and electrons (3 eV–50 kV) crosslink and immobilize QDs down to tens of nm while preserving the luminescent properties.

An Instructional Two-Dimensional Diffraction Laboratory Using Patterns Created with Electron-Beam Lithography

2002 ◽  
Vol 760 ◽  
Author(s):  
Colin Inglefield ◽  
Royce Anthon
Keyword(s):  
Electron Beam ◽  
Undergraduate Students ◽  
Electron Beam Lithography ◽  
Materials Science ◽  
Reciprocal Lattice ◽  
Real Space ◽  
Two Dimensional ◽  
Solid State Physics ◽  
Modern Physics ◽  
Order Of Magnitude

ABSTRACTAn instructional laboratory in two-dimensional diffraction is discussed. The experiment is appropriate for undergraduate students in materials science, solid-state physics (as was the case with our group), modern physics, or optics. The experiment is performed using visible light from a laser incident on a 2D lattice of gold dots deposited with electron beam lithography on a glass substrate. The pattern is microscopic with a lattice constant on the same order of magnitude as the wavelength of light used. Students observe the diffraction pattern, and then quantitatively determine the positions of maxima. These data are used by the students to reconstruct the (real space) microscopic lattice. The students can simulate the experiment with software that computes reciprocal lattice and diffraction patterns for an arbitrary 2D lattice.

scholarly journals Photoreflectance study of the GaAs buffer layer in InAs/GaAs quantum dots

2017 ◽  
Vol 30 (4) ◽  
pp. 56-60
Author(s):  
Diego Javier Sánchez Trujillo ◽  
Jhon Jairo Prías Barragán ◽  
Hernando Ariza Calderón ◽  
Álvaro Orlando Pulzara Mora ◽  
Máximo López López
Keyword(s):  
Quantum Dots ◽  
Electric Field ◽  
Buffer Layer ◽  
Surface Passivation ◽  
Bending Energy ◽  
Gaas Sample ◽  
Band Bending ◽  
Gaas Buffer Layer ◽  
Order Of Magnitude ◽  
The Difference

GaAs buffer layer in InAs/GaAs quantum dots (QDs) was investigated by Photoreflectance (PR) technique at 300 K. PR spectra obtained were compared with commercial GaAs sample PR spectra, and they were analyzed by using the derivative Lorentzian functions as proposed by Aspnes in the middle field regimen. PR spectra in InAs/GaAs QDs sample was attributed to the photoreflectance response in the GaAs buffer layer. Band bending energies were calculated for laser intensities from 1 mW to 21 mW. The photoreflectance comparative study in the samples was realized considering the difference in the parameters: electric field on the surface, broadening parameter, energy gained by photoexcited carriers due to the electric field applied, frequency of light and heavy holes and band bending energy values. The results suggest that the presence of InAs quantum dots increases the light and heavy holes frequencies and the band bending energy values; and decreases the electric field on the surface, the broadening parameter and the energy gained by photoexcited carriers. We found that InAs QDs presence modifies the surface electrical field around one order of magnitude in the GaAs buffer layer and this behavior can be attributed to surface passivation.

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