Abstract
We have investigated the optical and the structural properties of strained In1-xGaxAsyP1-y/InP and strain compensated In1-xGaxAsyP1-y/In1-zGazAsqP1-q/InP multi-quantum well heterostructures grown by low-pressure metalorganic vapor phase epitaxy at different growth conditions. Our results indicate an increase of the compositional fluctuation of quaternary materials as the alloy composition moves from the outer spinodal isotherm into the miscibility gap region. In1-xGaxAsyP1-y layers grown at high tensile strained values exhibit a three-dimensional-like growth mode. Strain compensated structures revealed the presence of a broad photoluminescence emission band below the fundamental quantum well transition, well defined elongated features along the [011] direction and interface undulations. All these effects were found to be strongly dependent on the growth temperature and the number of wells.
Highlights
In recent years In1-xGaxAsyP1-y/InP quaternary alloys emitting in the near infrared spectral region have proved to be of fundamental technological importance, due to their role as active layers in semiconductor laser diodes, photodetectors, optical amplifiers and modulators for teleco mmunication applications
We investigated the optical and the structural properties of strained In1-xGaxAsyP1-y /InP heterostructures grown by low-pressure (LP) Metalorganic Vapor Phase Epitaxy (MOVPE) at different growth temperatures and with mismatches (ε) ranging from -0.75% to +1%, as well as strain compensated In1-xGaxAsyP1-y/In1-zGazAsqP1-q/InP multi-quantum well (MQW) heterostructures
We investigated three different types of heterostructures: i) Type-I: strained In1-xGaxAsyP1-y (λ ~ 1670 nm, ε = +1% and λ ~ 1300 nm, ε = -0.5%) 30 nm thick followed by a InP cap layer 3 nm thick; ii) Type-II: tensile and compressive In1-xGaxAsyP1-y/InP-MQW structures, and iii) Type-III: In1-xGaxAsyP1-y/In1-zGazAswP1-w/InP-MQW with strain compensation
Summary
In recent years In1-xGaxAsyP1-y/InP quaternary alloys emitting in the near infrared spectral region have proved to be of fundamental technological importance, due to their role as active layers in semiconductor laser diodes, photodetectors, optical amplifiers and modulators for teleco mmunication applications. The development of advanced epitaxial techniques such as Molecular-Beam Epitaxy (MBE), Chemical-Beam Epitaxy (CBE) and Metalorganic Vapor Phase Epitaxy (MOVPE), enabled the fabrication of superior performance InGaAs(P)/InP strained quantum well heterostructures devices[1,2,3]. These new structures provide a great degree of freedom in the selection of chemical composition of In1-xGaxAsyP1-y alloys with a considerably wide range of the optical spectral emission wavelengths varying from 1000 nm up to 2000 nm. Our results confirm the anisotropic behavior of strain compensated structures obtained by Gas Source Molecular Beam Epitaxy (GSMBE)[4] and LP-MOVPE5,6
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
