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Published on: May 10, 2021
Composition analysis of semiconductor quantum wells by energy filtered convergent-beam electron diffraction
1Université des Sciences et Technologies de Lille, Bâtiment C6, 59655 Villeneuve d'Ascq cedex, France. damien.jacob@univ-lille1.fr
Ultramicroscopy
|July 17, 2007
Summary
Energy-filtered convergent-beam electron diffraction (EFCBED) determines buried semiconductor quantum well composition. This method analyzes Bragg line intensities to reveal strain and composition with high accuracy.
Area of Science:
- Materials Science
- Solid State Physics
- Nanotechnology
Background:
- Semiconductor quantum wells are crucial for advanced electronic and optoelectronic devices.
- Accurate determination of chemical composition in buried quantum wells is challenging.
- Strain and composition variations impact device performance.
Purpose of the Study:
- To develop and validate a method for determining the chemical composition of buried semiconductor strained quantum wells.
- To utilize energy-filtered convergent-beam electron diffraction (EFCBED) for quantitative analysis.
- To assess the accuracy and limitations of the proposed technique.
Main Methods:
- Quantitative analysis of high-order Bragg line intensities in EFCBED patterns from plan-view samples.
- Determination of the displacement vector R caused by quantum well deformation.
- Application to In(x)Ga(1-x)As quantum wells within a GaAs matrix.
Main Results:
- The method successfully determines the composition of buried In(x)Ga(1-x)As quantum wells.
- Relative uncertainty in indium content (x) measurement is less than 5%.
- Potential for detecting slight compositional fluctuations within the growth plane.
Conclusions:
- EFCBED offers a powerful, quantitative approach for characterizing buried semiconductor nanostructures.
- The technique provides precise compositional information essential for device optimization.
- Further analysis of experimental parameters, like diffraction vector choice, is important for maximizing accuracy.
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