Photoluminescence analyses of hydrogenated amorphous silicon nitride thin films
Küçük Resim Yok
Tarih
2011
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Elsevier
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
Silicon-rich hydrogenated amorphous silicon nitride (a-SiNx:H) films were grown by plasma enhanced chemical vapor deposition (PECVD) with different r=NH3/SiH4 gas flow ratios. The optical absorption characteristics were analyzed by Fourier transform infrared (FTIR) and UV-visible transmittance spectroscopies. The recombination properties were investigated via photoluminescence (PL) measurements. As r was increased from 2 to 9, the PL emission color could be adjusted from red to blue with the emission intensity high enough to be perceived by naked eye at room temperature. The behaviors of the PL peak energy and the PL band broadness with respect to the optical constants were discussed in the frame of electron-phonon coupling and band tail recombination models. A semiquantitative analysis supported the band tail recombination model, where the recombination was found to be favored when the carriers thermalize to an energy level at which the band tail density of states (DOS) reduces to some fraction of the relevant band edge DOS. For the PL efficiency comparison of the samples with different nitrogen contents, the PL intensity was corrected for the absorbed intensity fraction of the incident PL excitation source. The resulted correlation between the PL efficiency and the subgap absorption tail width further supported the band tail recombination model. (C) 2011 Elsevier B.V. All rights reserved.
Açıklama
Anahtar Kelimeler
Hydrogenated amorphous silicon nitride, FTIR, UV-visible transmittance, Photoluminescence, Band tail recombination
Kaynak
Journal of Luminescence
WoS Q Değeri
Q1
Scopus Q Değeri
Q2
Cilt
131
Sayı
7
