Selvidge, Jennifer Norman, Justin Hughes, Eamonn T. Shang, Chen Jung, Daehwan Taylor, Aidan A. Kennedy, M. J. Herrick, Robert Bowers, John E. Mukherjee, Kunal 2024-01-19T16:33:13Z 2024-01-19T16:33:13Z 2021-09-02 2020-09-21 0003-6951 https://pubs.kist.re.kr/handle/201004/118107 Epitaxially integrated III-V semiconductor lasers for silicon photonics have the potential to dramatically transform information networks, but currently, dislocations limit performance and reliability even in defect-tolerant InAs quantum dot (QD)-based lasers. Despite being below the critical thickness, QD layers in these devices contain previously unexplained misfit dislocations, which facilitate non-radiative recombination. We demonstrate here that these misfit dislocations form during post-growth cooldown due to the combined effects of (1) thermal-expansion mismatch between the III-V layers and silicon and (2) mechanical hardening in the active region. By incorporating an additional sub-critical thickness, indium-alloyed "misfit dislocation trapping layer," we leverage these mechanical hardening effects to our advantage, displacing 95% of misfit dislocations from the QD layer in model structures. Unlike conventional dislocation mitigation strategies, the trapping layer reduces neither the number of threading dislocations nor the number of misfit dislocations. It simply shifts the position of misfit dislocations away from the QD layer, reducing the defects' impact on luminescence. In full lasers, adding a misfit dislocation trapping layer both above and below the QD active region displaces misfit dislocations and substantially improves performance: we measure a twofold reduction in lasing threshold currents and a greater than threefold increase in output power. Our results suggest that devices employing both traditional threading dislocation reduction techniques and optimized misfit dislocation trapping layers may finally lead to fully integrated, commercially viable silicon-based photonic integrated circuits. English AMER INST PHYSICS QUANTUM-DOT LASERS GAAS/ALGAAS LASERS SI RELAXATION GLIDE Defect filtering for thermal expansion induced dislocations in III-V lasers on silicon Article 10.1063/5.0023378 1 APPLIED PHYSICS LETTERS, v.117, no.12 APPLIED PHYSICS LETTERS 117 12 scie scopus 000574437300001 2-s2.0-85091744723 Physics, Applied Physics Article QUANTUM-DOT LASERS GAAS/ALGAAS LASERS SI RELAXATION GLIDE