Adatom migration effects during molecular beam epitaxial growth of InGaAs/GaAs quantum wells on patterned substrates with vertical sidewalls: Blue shift in luminescence spectra
نویسندگان
چکیده
We have studied the blue shift in photoluminescence emission energy of pseudomorphic InGaAs/ GaAs quantum wells grown on patterned ~001! GaAs substrates with grooves and trenches having vertical sidewalls made by dry etching. Dependence of the blue shift, which can be as large as 51 meV, on the direction, feature size, and the etch depth of the patterns as well as the thickness of the buffer layer was observed, and is explained by the altered migration behavior of the adatoms. © 1996 American Institute of Physics. @S0003-6951~96!04308-X#
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