In-situ curvature monitoring and X-ray diffraction study of InGaAsP/InGaP quantum wells

Journal Article · Tue Jun 20 00:00:00 EDT 2017 · Journal of Crystal Growth

DOI:https://doi.org/10.1016/j.jcrysgro.2017.06.019· OSTI ID:1393376

Sayed, Islam E. H. ^[1]; Jain, Nikhil ^[2]; Steiner, Myles A. ^[2]; Geisz, John F. ^[2]; Dippo, Pat ^[2]; Kuciauskas, Darius ^[2]; Colter, Peter C. ^[3]

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1. North Carolina State Univ., Raleigh, NC (United States); National Renewable Energy Lab. (NREL), Golden, CO (United States)
2. National Renewable Energy Lab. (NREL), Golden, CO (United States)
3. North Carolina State Univ., Raleigh, NC (United States)

The use of InGaAsP/InGaP quantum well structures is a promising approach for subcells in next generation multi-junction devices due to their tunable bandgap (1.50-1.80 eV) and for being aluminum-free. Despite these potentials, the accumulation of stress during the growth of these structures and high background doping in the quantum well region have previously limited the maximum number of quantum wells and barriers that can be included in the intrinsic region and the sub-bandgap external quantum efficiency to less than 30.0%. In this paper, we report on the use of in-situ curvature monitoring by multi-beam optical stress (MOS) sensor measurements during the growth of this quantum well structure to monitor the stress evolution in these thin films. A series of In_0.32Ga_0.68AsP/In_0.49Ga_0.51P quantum wells with various arsine to phosphine ratios have been analyzed by in-situ curvature monitoring and X-ray diffraction (XRD) to obtain nearly strain-free lattice matched structures. Sharp interfaces, as indicated by the XRD fringes, have been achieved by using triethyl-gallium and trimethyl-gallium as gallium precursors in InGaAsP and InGaP, respectively, with constant flows of trimethyl-indium and phosphine through the entire quantum well structure. The effect of the substrate miscut on quantum well growth was compared and analyzed using XRD, photoluminescence and time resolved photoluminescence. As a result, a 100 period quantum well device was successfully grown with minimal stress and approximately flat in-situ curvature.

• Research Organization: National Renewable Energy Lab. (NREL), Golden, CO (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE), Renewable Power Office. Solar Energy Technologies Office
• Grant/Contract Number: AC36-08GO28308
• OSTI ID: 1393376
• Alternate ID(s): OSTI ID: 1550182
• Report Number(s): NREL/JA-5J00-68858
• Journal Information: Journal of Crystal Growth, Vol. 475, Issue C; ISSN 0022-0248
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
metalorganic chemical vapor deposition
quantum wells
semiconducting III-V materials
semiconducting gallium arsenide
semiconducting indium gallium phosphide
solar cells