On the onset of strain relaxation in the Al0.45Ga0.55As/InxGa1−xAs active region in quantum cascade laser structures. Issue 5 (14th September 2017)

• Record Type: Journal Article
• Authors: Sankowska, Iwona; Gutowski, Piotr; Jasik, Agata; Czuba, Krzysztof; Dabrowski, Jerzy; Bugajski, Maciej
• Is Part Of: Journal of applied crystallography. Volume 50:Issue 5(2017)
• Page Start: 1376
• Page End: 1381
• Publication Date: 2017-09-14
• Subjects: superlattices -- dislocation density -- diffuse scattering -- relaxation mechanisms; Crystallography -- Periodicals; 548.05
• DOI: 10.1107/S1600576717011815
• Languages: English
• ISSNs: 0021-8898

Abstract

Abstract : The onset of the strain relaxation process has been studied by examination of the diffuse scattering observed on symmetrical reciprocal‐space maps. It is shown that the size and shape of the diffuse scattering are closely related to the density of dislocations. Abstract : The Al0.45 Ga0.55 As/In x Ga1− x As active regions in quantum cascade laser structures grown on (001) GaAs substrates were investigated using the high‐resolution X‐ray diffraction method. The onset of the strain relaxation process has been studied. Reciprocal‐space mapping showed that diffuse scattering is visible in the early stage of relaxation for the structure with x = 2.64% in the In x Ga1− x As layers. It has been proved that the diffuse scattering is the result of misfit dislocations generated by partial relaxation of the structures. The integration of the diffuse scattering has enabled determination of the dislocation density.