Structural and optical characteristics of Er-doped SRSO layers deposited by the confocal sputtering technique

Abstract

Er-doped silicon-rich silicon oxide layers have been grown at 600 1C by magnetron co-sputtering of three confocal cathodes (Si, SiO 2 and Er 2 O 3) in pure argon plasma. The structural and optical properties of the layers were examined in the function of deposition and annealing conditions. It was shown that the increase of the RF power density applied on the Si cathode from 0.74 to 2.07 W cm À2 , while maintaining constant RF power on the two other cathodes, allows a fine engineering of the Si excess from 5 to 15 at%. The Er content was evaluated to 1 Â10 21 at cm À3. A high Er 3+ emission was observed under non-resonant (476 nm) excitation from as-deposited layers, which was significantly improved after annealing at 600 1C. The Er PL was found to be much more intense than the best samples reported so far, which was annealed at 900 1C and contains, however, lower Er content (5.4 Â 10 20 at cm À3) and Si excess (7 at% of Si). The Er emission lifetime was found to be about 6 ms for low Si excess (5 at%) and 1-2 ms for high Si excess. Upon reducing the Er content by a factor of three, the Er 3+ PL intensity was further increased and the lifetime reached 5.5 ms, suggesting a notable increase of the fraction of coupled Er ions.

Current transport and electroluminescence mechanisms in thin SiO2 films containing Si nanocluster-sensitized erbium ions

“…More details on the deposition process can be found elsewhere. 17 In total, three different SiO x : Er layers were fabricated, with thicknesses around 30 nm. Thickness was determined by spectroscopic ellipsometry measurements.…”

Optically active Er3+ ions in SiO2 codoped with Si nanoclusters

“…Sample A was grown at 500°C under argon pressure by the cosputtering of three targets ͑SiO 2 , Er 2 O 3 , and Si͒, 15 while sample B was deposited at 100°C under argon-hydrogen mixture by the cosputtering of pure SiO 2 and Er 2 O 3 targets. 16 These samples are the result of an optimization process until achieving maximum PL signal and total lifetime under 476 nm excitation, which is not resonant with an Er 3+ direct transition.…”

Modeling of optical amplifier waveguide based on silicon nanostructures and rare earth ions doped silica matrix gain media by a finite-difference time-domain method: comparison of achievable gain with Er3+or Nd3+ions dopants

“…The active layers doped with RE 3+ are grown by magnetron sputtering technique as described in references. [8][9][10] Those composite layers contain silicon nanograins (Si-ng) and RE 3+ ions dispersed in non-stoichiometric Silicon oxide (SiO x ) as schematically presented of figure 2. Those Si-ng act as sensitizers of RE 3+ ions in their vicinity by a mechanism of energy transfer and therefore enhance their excitability by several order of magnitude.…”