Strong 1.54 μm luminescence from erbium-doped porous silicon

Optical excitation of Er ions with 1.5 μm luminescence via the luminescent state in Si nanocrystallites embedded in SiO2 matrices

“…5 Nanostructuring has been investigated for the prevention of this thermal quenching. [6][7][8][9][10][11][12] In addition, Si nanocrystallites have advantages of ͑a͒ large absorption cross sections (10 Ϫ16 -10 Ϫ14 cm 2 , depending on excitation energy͒ 13 compared to Er ions (10 Ϫ21 cm 2 ); 14 ͑b͒ continuous absorption bands; 15 ͑c͒ a high concentration of active Er ions (2 ϫ10 20 cm Ϫ3 ) 16 compared to those in Si crystals (1.3 ϫ10 18 cm Ϫ3 ); 4 and ͑d͒ long-lived excitation source 17,18 compared to Er decay time. 19 Therefore, Er-doped SiO 2 films, including Si nanocrystallites (nc-Si/SiO 2 ) as sensitizers, can be also applied to compact optical amplifiers at 1.5 m, pumped by laser diodes or flash lamps.…”

Er3+ Doping conditions of planar porous silicon waveguides

“…Er luminescence efficiency at room temperature for a given host depends on both the temperature and the time of annealing treatments. Moreover, the presence of oxygen in the matrix is known to improve Er luminescence intensity [3,4,6,18]. Some authors [4,26,27] have reported that Er is optically active when Er-O, Si-Er-O complexes are formed whereas Si-Er complexes would not be.…”

“…The first-step is usually performed in an oxygen environment with temperatures up to 800 8C [18,19] to oxidize the porous silicon matrix. The second-step for Er activation and diffusion in the matrix is performed at higher temperatures because of the low diffusion coefficient of Er in Si (10 À14 cm 2 /s at 1000 8C) [20].…”

Luminescence of Lanthanides from Xerogels Embedded in Mesoporous Matrices

“…Si(OC 2 H 5 ) 4 and Fe(OH) 3 were used as the precursors. Penetration of the sols through the channel of the pores was concluded from observation the components of xerogels with secondary-ion mass spectroscopy (SIMS) and secondary-neutral mass spectroscopy (SNMS) [8,9], cross-section TEM-images [13], and Rutherford backscattering (RBS) [12] in porous silicon 0.3 [13], 1.5 [12], and 5 [8] µm thick.…”

“…Interest in fabrication of the structure xerogel/porous silicon was initiated in 1990s by a challenging problem of development light-emitting devices for visible and infrared emission on silicon basis. In the experiments micro- [7], meso- [8][9][10][11][12][13][14], and macroporous [15] silicon was used for spin-on deposition of coatable sols containing erbium nitride dissolved in water and ethanol. Si(OC 2 H 5 ) 4 and Fe(OH) 3 were used as the precursors.…”