InGaN epilayer characterization by microfocused x-ray reciprocal space mapping

DOI: 10.1063/1.3658619

Authors: V. Kachkanov (Diamond Light Source) , I. P. Dolbnya (Diamond Light Source) , K. P. O'Donnell (University of Strathclyde) , R. W. Martin (University of Strathclyde) , P. R. Edwards (University of Strathclyde) , S. Pereira (University of Aveiro)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Applied Physics Letters , VOL 99 (18)

State: Published (Approved)
Published: November 2011

Abstract: We report the use of microfocused three-dimensional x-ray reciprocal space mapping to study InGaN epilayers with average InN content ∼20%-22%. Analysis of the full volume of reciprocal space, while probing samples on the microscale with a focused x-ray beam, allowed us to gain valuable information about the nanostructure of InN-rich InGaN epilayers. It is found that “seed” InGaN mosaic nanocrystallites are twisted with respect to the ensemble average and strain-free. The initial stages of InGaN-on-GaN epitaxial growth, therefore, conform to the Volmer-Weber growth mechanism with “seeds” nucleated on strain fields generated by the a-type edge dislocations.

Journal Keywords: III-V semiconductors; Epitaxy; X-ray diffraction; Reciprocal space; Crystalline solids

Diamond Keywords: Semiconductors; Alloys

Subject Areas: Physics, Materials


Instruments: B16-Test Beamline

Added On: 15/11/2011 09:54

Discipline Tags:

Physics Electronics Materials Science Metallurgy

Technical Tags:

Diffraction