SiGeSn Ternaries for Efficient Group IV Heterostructure Light Emitters. Issue 16 (3rd February 2017)

• Record Type: Journal Article
• Authors: von den Driesch, Nils; Stange, Daniela; Wirths, Stephan; Rainko, Denis; Povstugar, Ivan; Savenko, Aleksei; Breuer, Uwe; Geiger, Richard; Sigg, Hans; Ikonic, Zoran; Hartmann, Jean‐Michel; Grützmacher, Detlev; Mantl, Siegfried; Buca, Dan
• Is Part Of: Small. Volume 13:Issue 16(2017)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2017-02-03
• Subjects: group IV -- heterostructures -- light emitting diodes -- SiGeSn -- silicon photonics; Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.201603321
• Languages: English
• ISSNs: 1613-6810

Abstract

Abstract : SiGeSn ternaries are grown on Ge‐buffered Si wafers incorporating Si or Sn contents of up to 15 at%. The ternaries exhibit layer thicknesses up to 600 nm, while maintaining a high crystalline quality. Tuning of stoichiometry and strain, as shown by means of absorption measurements, allows bandgap engineering in the short‐wave infrared range of up to about 2.6 µm. Temperature‐dependent photoluminescence experiments indicate ternaries near the indirect‐to‐direct bandgap transition, proving their potential for ternary‐based light emitters in the aforementioned optical range. The ternaries' layer relaxation is also monitored to explore their use as strain‐relaxed buffers, since they are of interest not only for light emitting diodes investigated in this paper but also for many other optoelectronic and electronic applications. In particular, the authors have epitaxially grown a GeSn/SiGeSn multiquantum well heterostructure, which employs SiGeSn as barrier material to efficiently confine carriers in GeSn wells. Strong room temperature light emission from fabricated light emitting diodes proves the high potential of this heterostructure approach. Abstract : Group IV SiGeSn ternaries are epitaxially grown directly on Ge‐buffered Si wafers. Band structure engineering by independent tuning of Si and Sn incorporation yields bandgaps in the short‐wave infrared range and, with appropriate stoichiometry, ternaries near the indirect‐to‐direct bandgap transition. Aiming for light emitters, a GeSn/SiGeSn multiquantum well heterostructure is epitaxially formed, proving strong room temperature electroluminescence from fabricated LEDs.