1. Fabrication and characterization of Si1−xGex nanocrystals in as-grown and annealed structures: a comparative study
- Author
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Jon Tomas Gudmundsson, A.V. Maraloiu, Ionel Stavarache, H. G. Svavarsson, Magdalena Lidia Ciurea, M. T. Sultan, Andrei Manolescu, Valentin S. Teodorescu, Verkfræðideild (HR), Department of Engineering (RU), Raunvísindastofnun (HÍ), Science Institute (UI), Tæknisvið (HR), School of Technology (RU), Verkfræði- og náttúruvísindasvið (HÍ), School of Engineering and Natural Sciences (UI), Háskólinn í Reykjavík, Reykjavik University, Háskóli Íslands, and University of Iceland
- Subjects
HRTEM ,Annealing (metallurgy) ,stem-haadf ,Nucleation ,General Physics and Astronomy ,Nanoparticle ,lcsh:Chemical technology ,lcsh:Technology ,Full Research Paper ,tem ,Nanotechnology ,General Materials Science ,lcsh:TP1-1185 ,Enhanced photoconductivity ,German (frumefni) ,high-power impulse magnetron sputtering (hipims) ,lcsh:Science ,SiGe nanocrystals ,STEM-HAADF ,magnetron sputtering ,Quantum dots ,lcsh:QC1-999 ,Nanoscience ,High-power impulse magnetron sputtering (HiPIMS) ,Litróf ,Transmission electron microscopy ,hrtem ,Kísill ,Efnasambönd ,Optoelectronics ,photocurrent spectra ,Magnetron sputtering ,Eðlisfræði ,Materials science ,grazing incidence xrd (gixrd) ,Rafeindaverkfræði ,Frumefni ,Rafeindir ,Efnafræði ,Smásjár ,Electrical and Electronic Engineering ,sige nanocrystals in sio2/sige/sio2 multilayers ,High-resolution transmission electron microscopy ,Photocurrent spectra ,Photoluminescence ,Photocurrent ,SiO2/SiGe/SiO2 multilayers ,business.industry ,lcsh:T ,Sputter deposition ,Nanótækni ,Ljósfræði ,Súrefni ,TEM ,Nanoparticles ,lcsh:Q ,High-power impulse magnetron sputtering ,business ,Grazing incidence XRD (GIXRD) ,lcsh:Physics - Abstract
Publisher's version (útgefin grein), Multilayer structures comprising of SiO2/SiGe/SiO2 and containing SiGe nanoparticles were obtained by depositing SiO2 layers using reactive direct current magnetron sputtering (dcMS), whereas, Si and Ge were co-sputtered using dcMS and high-power impulse magnetron sputtering (HiPIMS). The as-grown structures subsequently underwent rapid thermal annealing (550-900 degrees C for 1 min) in N-2 ambient atmosphere. The structures were investigated using X-ray diffraction, high-resolution transmission electron microscopy together with spectral photocurrent measurements, to explore structural changes and corresponding properties. It is observed that the employment of HiPIMS facilitates the formation of SiGe nanoparticles (2.1 +/- 0.8 nm) in the as-grown structure, and that presence of such nanoparticles acts as a seed for heterogeneous nucleation, which upon annealing results in the periodically arranged columnar self-assembly of SiGe core-shell nanocrystals. An increase in photocurrent intensity by more than an order of magnitude was achieved by annealing. Furthermore, a detailed discussion is provided on strain development within the structures, the consequential interface characteristics and its effect on the photocurrent spectra., M-ERA. NET project PhotoNanoP UEFISCDI Contract no. 33/2016, PCE project UEFISCDI Contract no. 122/2017 and by Romanian Ministry of Research and Innovation through NIMP Core Program PN19-03, contract no. 21 N/08.02.2019 and by the Technology Development Fund of the Icelandic Centre for Research, grant no. 159006-0611., "Peer Reviewed"
- Published
- 2019