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Title: Enhancement of minority carrier lifetime of GaInP with lateral composition modulation structure grown by molecular beam epitaxy

We report the enhancement of the minority carrier lifetime of GaInP with a lateral composition modulated (LCM) structure grown using molecular beam epitaxy (MBE). The structural and optical properties of the grown samples are studied by transmission electron microscopy and photoluminescence, which reveal the formation of vertically aligned bright and dark slabs corresponding to Ga-rich and In-rich GaInP regions, respectively, with good crystal quality. With the decrease of V/III ratio during LCM GaInP growth, it is seen that the band gap of LCM GaInP is reduced, while the PL intensity remains high and is comparable to that of bulk GaInP. We also investigate the minority carrier lifetime of LCM structures made with different flux ratios. It is found that the minority carrier lifetime of LCM GaInP is ∼37 times larger than that of bulk GaInP material, due to the spatial separation of electrons and holes by In-rich and Ga-rich regions of the LCM GaInP, respectively. We further demonstrate that the minority carrier lifetime of the grown LCM GaInP structures can easily be tuned by simply adjusting the V/III flux ratio during MBE growth, providing a simple yet powerful technique to tailor the electrical and optical properties at will. The exceptionallymore » high carrier lifetime and the reduced band gap of LCM GaInP make them a highly attractive candidate for forming the top cell of multi-junction solar cells and can enhance their efficiency, and also make them suitable for other optoelectronics devices, such as photodetectors, where longer carrier lifetime is beneficial.« less
Authors:
; ; ; ;  [1] ;  [1] ; ;  [2] ;  [1] ;  [3]
  1. School of Information and Communications, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of)
  2. School of Material Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of)
  3. (Korea, Republic of)
Publication Date:
OSTI Identifier:
22308522
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 4; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CARRIER LIFETIME; CRYSTALS; EFFICIENCY; ELECTRIC CONTACTS; ELECTRONS; GALLIUM COMPOUNDS; HOLES; INDIUM COMPOUNDS; MODULATION; MOLECULAR BEAM EPITAXY; OPTICAL PROPERTIES; PHOSPHORUS COMPOUNDS; PHOTODETECTORS; PHOTOLUMINESCENCE; SEMICONDUCTOR JUNCTIONS; SLABS; SOLAR CELLS; TRANSMISSION ELECTRON MICROSCOPY