Hydrogenation for defect passivation in (Si)GeSn alloys

Recent reports of minority carrier lifetimes in GeSn/SiGeSn MQWs suggest improvements are required to fully realize the potential of SiGeSn material system for near- to mid-IR imaging. While systematic efforts are underway to engineer growth methods aimed at minimizing the formation of material defects, the development of alternative methods like hydrogen bulk passivation for defect mitigation is advisable. EPIR proposes to employ technology patented by the proposed principal investigators to advance the technology of SiGeSn ternary alloys by passivating charge carrier scattering and lifetime-limiting defects with hydrogen or deuterium, and hence increasing minority carrier mobilities and lifetimes. In future efforts the hydrogenation process will be tuned to further improve the performance of other material systems like InAsSbBi alloys that experience similar limitations due to non-equilibrium growth conditions.  EPIR’s strong background in semiconductor and materials theory means that it can comprehensively assess the efficacy of hydrogenation and improve the tuning of hydrogenation parameters for SiGeSn alloys. The SiGeSn materials enhanced through the proposed hydrogenation process would lead to advanced, large-format, low noise, Ge-based IR focal plane arrays benefiting from the established, high-yield, high-throughput manufacturing of Si CMOS and thermal compatibility between the read-out circuits and the detector arrays.