Open AccessStudy of the microstructure information of GaAs epilayers grown on silicon substrate using synchrotron radiation
Author(s) -
Kumar Ravi,
Dixit V. K.,
Sinha A. K.,
Ganguli Tapas,
Mukherjee C.,
Oak S. M.,
Sharma T. K.
Publication year - 2016
Publication title -
journal of synchrotron radiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 99
ISSN - 1600-5775
DOI - 10.1107/s1600577515019955
Subject(s) - synchrotron radiation , materials science , synchrotron , diffraction , microstructure , coherence length , advanced photon source , substrate (aquarium) , coherence (philosophical gambling strategy) , silicon , optics , tilt (camera) , synchrotron radiation source , radiation , x ray , beam (structure) , crystallography , optoelectronics , physics , beamline , condensed matter physics , chemistry , superconductivity , mechanical engineering , oceanography , engineering , quantum mechanics , geology , metallurgy
Williamson–Hall (WH) analysis is a well established method for studying the microstructural properties of epilayers grown on foreign substrates. However, the method becomes inapplicable in specific cases where the structure factor considerations and the presence of anti‐phase domains forbid the data acquisition for certain reflections in conventional high‐resolution X‐ray diffraction (HRXRD) measurements. Here, this limitation is overcome by exploiting the large intensity (25 µW mm −2 ) and high photon energy (15.5 keV) of the X‐ray beam obtained from a synchrotron radiation source. The lateral coherence length, vertical coherence length, tilt and micro‐strain of GaAs epilayers grown on Si substrate have been successfully measured using the conventional WH analysis. The microstructure information obtained from the conventional WH analysis based on the data acquired at the synchrotron radiation source is in reasonable agreement with the results obtained from atomic force microscope and surface profiler measurements. Such information cannot be obtained on a laboratory‐based HRXRD system where modification of the WH method by involving a set of parallel asymmetric crystallographic planes is found to be essential. However, the information obtained from the modified WH method is along a different crystallographic orientation.