On the spectral difference between electroluminescence and photoluminescence of Si nanocrystals: a mechanism study of electroluminescence

• Published in: Journal of nanoparticle research : an interdisciplinary forum for nanoscale science and technology Vol. 15; no. 11; pp. 1 - 7
• Main Authors: Wang, Dong-Chen, Chen, Jia-Rong, Zhu, Jiang, Lu, Chen-Tian, Lu, Ming
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.11.2013; Springer; Springer Nature B.V
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Electroluminescence; Exact sciences and technology; Inorganic Chemistry; Lasers; Materials Science; Mathematical models; Nanocomposites; Nanocrystalline materials; Nanocrystals; Nanoparticles; Nanoscale materials and structures: fabrication and characterization; Nanostructure; Nanotechnology; Optical Devices; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures; Optics; Photoluminescence; Photonics; Physical Chemistry; Physics; Pollution monitoring; Research Paper; Silicon; Spectra; Working conditions; Electroluminescence; Modeling and simulation; Si nanocrystal; Carrier transport; Photoluminescence; Digital simulation; Theoretical study; Spectral line shift; Blue shift; Experimental result; Light emission; Modelling; Nanostructured materials; Nanocrystal
• ISSN: 1388-0764; 1572-896X
• DOI: 10.1007/s11051-013-2063-x

Spectral shift, especially blueshift, in peak position of electroluminescence (EL) spectrum of Si nanocrystal (Si-nc) with respect to its photoluminescence (PL) counterpart has been often observed. Explanations for the spectral difference are different for different EL mechanisms adopted. To gain a relevant picture of the EL process, in this work, we analyze three EL mechanisms that are mainly applied nowadays, i.e., the model of defect light emission, that of band-filling, and that of Si-nc size selection by the carrier energy. Different Si-nc samples and working conditions are designed and their EL and PL emissions monitored according to the predictions of the three models. It is concluded that the observed EL is mainly of Si-nc-related origin. The experimental results are more consistent with the model of Si-nc size selection.