Abstract
InGaAs quantum wells embedded in GaAs nanowires can serve as compact near-infrared emitters for direct integration onto Si complementary metal oxide semiconductor technology. While the core-shell geometry in principle allows for a greater tuning of composition and emission, especially farther into the infrared, the practical limits of elastic strain accommodation in quantum wells on multifaceted nanowires have not been established. One barrier to progress is the difficulty of directly comparing the emission characteristics and the precise microstructure of a single nanowire. Here we report an approach to correlating quantum well morphology, strain, defects, and emission to understand the limits of elastic strain accommodation in nanowire quantum wells specific to their geometry. We realize full 3D Bragg coherent diffraction imaging (BCDI) of intact quantum wells on vertically oriented epitaxial nanowires, which enables direct correlation with single-nanowire photoluminescence. By growing In0.2Ga0.8As quantum wells of distinct thicknesses on different facets of the same nanowire, we identified the critical thickness at which defects are nucleated. A correlation with a traditional transmission electron microscopy analysis confirms that BCDI can image the extended structure of defects. Finite element simulations of electron and hole states explain the emission characteristics arising from strained and partially relaxed regions. This approach, imaging the 3D strain and microstructure of intact nanowire core-shell structures with application-relevant dimensions, can aid the development of predictive models that enable the design of new compact infrared emitters.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 20281-20293 |
| Number of pages | 13 |
| Journal | ACS nano |
| Volume | 16 |
| Issue number | 12 |
| DOIs | |
| State | Published - Dec 27 2022 |
Funding
M.O.H., C.H., and L.J.L. acknowledge the support of the National Science Foundation via DMR-1611341 and DMR 1905768. M.O.H. acknowledges support via the NSF GRFP. G.K, J.J.F., and P.S. acknowledge support from the Deutsche Forschungsgemeinschaft (DFG) via Project Grants FI 947/4-1 and KO 4005/7-1, the Cluster of Excellence e-conversion (EXC2089/1-390776260), and the European Research Council (ERC project QUANtIC, ID: 771747). Bragg CDI experiments and data processing were supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Science and Engineering Division. CDI was performed at the Coherent Diffraction Imaging beamline 34-ID-C operated by the Advanced Photon Source at Argonne National Laboratory. This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science user facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. This work made use of the EPIC facility of the NUANCE Center at Northwestern University, which has received support from the Soft and Hybrid Nanotechnology Experimental (SHyNE) Resource (NSF ECCS-1542205), the MRSEC program (NSF DMR-1720139) at the Materials Research Center, the International Institute for Nanotechnology (IIN), the Keck Foundation, and the State of Illinois, through the IIN. The authors are also grateful for assistance from W. Cha, M. J. Moody, Z. Zhu, and J. Olding in performing CDI measurements, and M.O.H. thanks A. Davtyan for his useful discussions around experimental planning.
Keywords
- Bragg coherent diffraction imaging (BCDI)
- III-V semiconductors
- defects
- nanowires
- photoluminescence
- quantum well
ASJC Scopus subject areas
- General Engineering
- General Materials Science
- General Physics and Astronomy