Journal of Crystal Growth, Vol.466, 22-29, 2017
MBE growth of strain-compensated InGaAs/InAlAs/InP quantum cascade lasers
We investigate growth conditions for strain-compensated In0.67Ga0.33As/ln(0.36)Al(0.64)As/InP quantum cascade lasers (QCLs) by solid-source molecular beam epitaxy (SSMBE). The extensive discussion of growth procedures is presented. The technology was first elaborated for In0.53Ga0.47As/In0.52Al0.48As material system lattice matched to InP. After that QCLs with lattice matched active region were grown for validation of design and obtained material quality. The next step was elaboration of growth process and especially growth preparation procedures for strain compensated active regions. The grown structures were examined by HRXRD, AFM, and TEM techniques. The on-line implementation of obtained results in subsequent growth runs was crucial for achieving room temperature operating 4.4-mu m lasers. For uncoated devices with Fabry-Perrot resonator up to 250 mW of optical power per facet at 300 K was obtained under pulsed conditions. The paper focuses on MBE technology and presents developed algorithm for strain compensated QCL growth. (C) 2017 Elsevier B.V. All rights reserved.
Keywords:Molecular beam epitaxy;Semiconducting Ill-V materials;Quantum cascade lasers;High resolution X-ray diffraction