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Direct Measurement of Polarization-Induced Fields in GaN/AlN by Nano-Beam Electron Diffraction.

ABSTRACT: The built-in piezoelectric fields in group III-nitrides can act as road blocks on the way to maximizing the efficiency of opto-electronic devices. In order to overcome this limitation, a proper characterization of these fields is necessary. In this work nano-beam electron diffraction in scanning transmission electron microscopy mode has been used to simultaneously measure the strain state and the induced piezoelectric fields in a GaN/AlN multiple quantum well system.

SUBMITTER: Carvalho D

PROVIDER: S-EPMC4923855 | biostudies-other | 2016

REPOSITORIES: biostudies-other

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Direct Measurement of Polarization-Induced Fields in GaN/AlN by Nano-Beam Electron Diffraction.

Carvalho Daniel D Müller-Caspary Knut K Schowalter Marco M Grieb Tim T Mehrtens Thorsten T Rosenauer Andreas A Ben Teresa T García Rafael R Redondo-Cubero Andrés A Lorenz Katharina K Daudin Bruno B Morales Francisco M FM

Scientific reports 20160628

The built-in piezoelectric fields in group III-nitrides can act as road blocks on the way to maximizing the efficiency of opto-electronic devices. In order to overcome this limitation, a proper characterization of these fields is necessary. In this work nano-beam electron diffraction in scanning transmission electron microscopy mode has been used to simultaneously measure the strain state and the induced piezoelectric fields in a GaN/AlN multiple quantum well system. ...[more]

PMID: 27350322

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