N. H. Abd Raof and H. Abu Hassan and S.K. Mohd Bakhori and S. S. Ng and Z. Hassan
Structural and Optical Properties ofInxAlyGa1xyN Quaternary Alloys
1448 - 1451
2009
3
7
International Journal of Electronics and Communication Engineering
https://publications.waset.org/pdf/10639
https://publications.waset.org/vol/31
World Academy of Science, Engineering and Technology
Quaternary InxAlyGa1xyN semiconductors have
attracted much research interest because the use of this quaternary
offer the great flexibility in tailoring their band gap profile while
maintaining their latticematching and structural integrity. The
structural and optical properties of InxAlyGa1xyN alloys grown by
molecular beam epitaxy (MBE) is presented. The structural quality of
InxAlyGa1xyN layers was characterized using highresolution Xray
diffraction (HRXRD). The results confirm that the InxAlyGa1xyN
films had wurtzite structure and without phase separation. As the In
composition increases, the Bragg angle of the (0002) InxAlyGa1xyN
peak gradually decreases, indicating the increase in the lattice constant
c of the alloys. FWHM of (0002) InxAlyGa1xyN decreases with
increasing In composition from 0 to 0.04, that could indicate the
decrease of quality of the samples due to point defects leading to
nonuniformity of the epilayers. UVVIS spectroscopy have been used
to study the energy band gap of InxAlyGa1xyN. As the indium (In)
compositions increases, the energy band gap decreases. However, for
InxAlyGa1xyN with In composition of 0.1, the band gap shows a
sudden increase in energy. This is probably due to local alloy
compositional fluctuations in the epilayer. The bowing parameter
which appears also to be very sensitive on In content is investigated
and obtained b 50.08 for quaternary InxAlyGa1xyN alloys. From
photoluminescence (PL) measurement, green luminescence (GL)
appears at PL spectrum of InxAlyGa1xyN, emitted for all x at 530 nm
and it become more pronounced as the In composition (x) increased,
which is believed cause by gallium vacancies and related to isolated
native defects.
Open Science Index 31, 2009