Size dependence of lifetime and absorption cross section of Si nanocrystals embedded in SiO[sub 2]

Garcia, C.; Garrido, B.; Pellegrino, P.; Ferre, R.; Moreno, J. A.; Morante, J. R.; Pavesi, L.; Cazzanelli, M.
March 2003
Applied Physics Letters;3/10/2003, Vol. 82 Issue 10, p1595
Academic Journal
Photoluminescence lifetimes and optical absorption cross sections of Si nanocrystals embedded in SiO[sub 2] have been studied as a function of their average size and emission energy. The lifetimes span from 20 µs for the smallest sizes (2.5 nm) to more than 200 µs for the largest ones (7 nm). The passivation of nonradiative interface states by hydrogenation increases the lifetime for a given size. In contrast with porous Si, the cross section per nanocrystal shows a nonmonotonic behavior with emission energy. In fact, although the density of states above the gap increases for larger nanocrystals, this trend is compensated by a stronger reduction of the oscillator strength, providing an overall reduction of the absorption cross section per nanocrystal for increasing size.


Related Articles

  • Charge storage and interface states effects in Si-nanocrystal memory obtained using low-energy Si[sup +] implantation and annealing. Kapetanakis, E.; Normand, P.; Tsoukalas, D.; Beltsios, K.; Stoemenos, J.; Zhang, S.; van den Berg, J. // Applied Physics Letters;11/20/2000, Vol. 77 Issue 21 

    Thin SiO[sub 2] oxides implanted by very-low-energy (1 keV) Si ions and subsequently annealed are explored with regards to their potential as active elements of memory devices. Charge storage effects as a function of Si fluence are investigated through capacitance and channel current...

  • Correlation between structural and optical properties of Si nanocrystals embedded in SiO[sub 2]: The mechanism of visible light emission. Garrido, B.; López, M.; González, O.; Pérez-Rodríguez, A.; Morante, J. R.; Bonafos, C. // Applied Physics Letters;11/13/2000, Vol. 77 Issue 20 

    The size distribution, band gap energy, and photoluminescence of silicon nanocrystals embedded in SiO[sub 2] have been measured by direct and independent methods. The size distribution is measured by coupling high-resolution and conventional electron microscopy in special imaging conditions. The...

  • Comparative study of the optical properties of porous silicon and the oxides SiO and SiO[sub 2]. Obraztsov, A. N.; Timoshenko, V. Yu.; Okushi, H.; Watanabe, H. // Semiconductors;Mar1999, Vol. 33 Issue 3, p323 

    The results of a comparative study of the optical absorption and photoluminescence in layers of porous silicon, silicon oxides (SiO and SiO[sub 2]), and powdered silicon are presented. It is found that the position of the absorption-band edge, determined from the data of photoacoustic...

  • Spectroscopic studies on Li2O-Nb2O5-SiO2:V2O5 glass ceramics embeded with nano ferroelectric crystals. Rao, Ch. Srinivasa; Srikumar, T.; Veeraiah, N. // International Journal of ChemTech Research;May/Jun2014, Vol. 6 Issue 3, p2039 

    In this study we have investigated some physical properties of Li2O-NbLi2OLi5-SiOLi2:VLi2OLi5 glass ceramics containing nano ferroelectric crystal phases. The glasses were synthesized by melt quenching technique and subsequently crystallized. The samples were characterized by XRD, SEM and DTA...

  • Large-scale Synthesis of β-SiC Nanochains and Their Raman/Photoluminescence Properties. Meng, Alan; Zhang, Meng; Gao, Weidong; Sun, Shibin; Li, Zhenjiang // Nanoscale Research Letters;Jan2011, Vol. 6 Issue 1, p1 

    lthough the SiC/SiO nanochain heterojunction has been synthesized, the chained homogeneous nanostructure of SiC has not been reported before. Herein, the novel β-SiC nanochains are synthesized assisted by the AAO template. The characterized results demonstrate that the nanostructures are...

  • Soft x-ray imaging and spectroscopy of single nanocrystals. Rockenberger, Jo¨rg; Nolting, Frithjof; Lu¨ning, Jan; Hu, Jiangtao; Alivisatos, A. Paul // Journal of Chemical Physics;4/8/2002, Vol. 116 Issue 14, p6322 

    Resonant photoemission electron microscopy (PEEM) at the Fe L[sub 3,2] absorption edge was utilized to image single γ-Fe[sub 2]O[sub 3] nanocrystals of 10 nm average diameter (∼20 000 Fe atoms) and to record soft x-ray absorption spectra of individual particles. Within the spectral...

  • Optical absorption and photoluminescence characteristics of Cd[sub 2]GeSe[sub 4] single crystals. Lee, Jeoung Ju; Park, Young Shin; Yang, Chang Soo; Kim, Kun Ho; Jin, Moon Seog; Kim, Wha Tek // Journal of Applied Physics;9/1/2002, Vol. 92 Issue 5, p2945 

    Cd[sub 2]GeSe[sub 4] single crystals were grown by using a modified Bridgmann method. The optical energy band gap obtained from the optical absorption measurement was about 1.922 ± 0.002 eV at 10 K and 1.707 ± 0.002 eV at 298 K. In the photoluminescence (PL) spectra measured at...

  • Electrical and optical properties of CuAlSe2 grown by iodine chemical vapor transport. Chichibu, S.; Shishikura, M.; Ino, J.; Matsumoto, S. // Journal of Applied Physics;8/1/1991, Vol. 70 Issue 3, p1648 

    Presents a study which examined the resistivities, carrier concentrations, optical absorption and photoluminescence of CuAlSe[sub2] single crystals grown by chemical vapor transport. Experimental details; Results and discusstion; Conclusion.

  • The Influence of Irradiation and Subsequent Annealing on Si Nanocrystals Formed in SiO[sub 2] Layers. Kachurin, G. A.; Yanovskaya, S. G.; Ruault, M.-O.; Gutakovskii, A. K.; Zhuravlev, K. S.; Kaitasov, O.; Bernas, H. // Semiconductors;Aug2000, Vol. 34 Issue 8, p965 

    Luminescent Si nanocrystals formed in SiO[sub 2] layers were irradiated with electrons and He[sup +] ions with energies of 400 and 25-130 keV, respectively. The effects of irradiation and subsequent annealing at 600-1000�C were studied by the methods of photoluminescence and electron...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics