Wan, ZeyuZeyuWanKamal, SaeidSaeidKamalQaiser, Muhammad HaroonMuhammad HaroonQaiserYang, Yun-ChengYun-ChengYangBritton, BenBenBrittonWu, Chao-HsinChao-HsinWuXia, GuangruiGuangruiXia2025-12-172025-12-172025-05-20[9798331556235]26938324https://www.scopus.com/record/display.uri?eid=2-s2.0-105022479887&origin=resultslisthttps://scholars.lib.ntu.edu.tw/handle/123456789/734698Partial vertical cavity surface emitting laser (VCSEL) structures, AlGaAs-based distributed Bragg reflector (DBR) with InGaAs/ GaAsP multi-quantum wells (MQWs), grown on Ge substrates were investigated and compared to conventional GaAs substrates. While both substrates demonstrated successful epitaxy, the Ge-based samples showed distinct differences in power-law behavior (β=1.03 vs. 1.34) and broader FWHM (34-44% increase), indicating higher defect densities. Despite these challenges, results confirm Ge's viability as a cost-effective, scalable substrate for AlGaAs-based VCSELs.falseconference paper10.1109/pn66844.2025.110971712-s2.0-105022479887