Thickness dependence of double crystal rocking curves and photoluminescence in ZnS epilayers grown on GaAs(100) and GaP(100)

• Published in: Applied surface science Vol. 151; no. 3; pp. 203 - 212
• Main Authors: Nam, Sungun, Yu, Young-Moon, O, Byungsung, Lee, Ki-Seon, Choi, Yong Dae, Jung, Yang-June
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.10.1999; Elsevier Science
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Double crystal rocking curve; Exact sciences and technology; Ii-vi semiconductors; Lattice constant; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of specific thin films; Photoluminescence; Physics; Structure and morphology; thickness; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thermal expansion coefficient; Thickness dependence; Thin film structure and morphology; ZnS/GaAs epilayer; ZnS/GaP epilayer; ST; Lattice constant; Thickness dependence; Photoluminescence; Double crystal rocking curve; LU; ZC; 61.10.Nz; 78.55.Et; ZnS/GaAs epilayer; Thermal expansion coefficient; XBD; ZnS/GaP epilayer; GD; GF; Zinc sulfides; Inorganic compounds; Epitaxy; Transition element compounds; Crystallinity; Experimental study; Lattice parameters; Thin films; Thickness; Thermal expansion; Energy gap; Tensile stress; Excitons; Hot wall growth; Morphology; Mismatch lattice
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/S0169-4332(99)00275-5

High quality ZnS/GaAs and ZnS/GaP epilayers are grown by hot wall epitaxy. The full width at half maximum (FWHM) of the double crystal rocking curves (DCRC) and photoluminescence (PL) are measured to investigate the crystalline quality of ZnS/GaAs and ZnS/GaP epilayers. The best value of the FWHM of the DCRC for ZnS/GaAs epilayers at 3.8 μm thickness is 373 arcsec, and for ZnS/GaP epilayers at 4.7 μm thickness of 173 arcsec. The PL spectra of ZnS/GaAs and ZnS/GaP epilayers reveal very strong near-edge emission peaks, no deep level peaks and self-activated peaks. The band gap energy E g for ZnS epilayer is measured at 3.729 eV at the room temperature. The tensile strain due to the lattice mismatch and the thermal expansion coefficient difference between ZnS epilayer and GaAs (or GaP) substrate is existed in ZnS epilayers. In this study, the thickness dependence of DCRC and PL for ZnS epilayers is analyzed taking into account the tensile strain.