Silicon nanocluster-sensitized emission from erbium: The role of stress in the formation of silicon nanoclusters

Abstract

Erbium-doped silicon-rich silicon oxide films deposited by plasma enhanced chemical vapor deposition suffer from compressive stress as deposited, which converts to a large tensile stress on annealing due to the release of hydrogen. Although the cracking that results from this stress can be avoided by patterning the films into ridges, significant stress remains along the ridge axis. Measurements of erbium photoluminescence sensitized by silicon nanoclusters in stressed and relaxed films suggest an important role for internal film stresses in promoting the phase separation of excess silicon into nanoclusters, which has previously been thought of as a thermally driven process.

Effects of the thickness on the properties of erbium‐doped silicon‐rich silicon oxide thin films

“…the thickness [18,29], (ii) the stress-induced effect which affects the phase separation and then the formation of Si-nc. [19] Concerning the PL properties, consistent results were obtained, as shown by the typical spectra of Fig. 3 for the thicker sample deposited at RT.…”

“…ness dependence in terms of nucleation barrier for Si nanoclusters [18] or stress-induced promotion of Si-nc formation [19]. This study aims at examining the influence of the layer thickness on the composition, microstructure and optical properties of SRSO: Er thin films deposited by magnetron co-sputtering.…”

Modification of erbium photoluminescence decay rate due to ITO layers on thin films of SiO2:Er doped with Si-nanoclusters

“…Although the material composition is intentionally identical for all samples, PL intensity does not depend linearly on the film thickness. This is due to the fact that difference in thickness leads to different stress in the samples, which affects nucleation and growth of Si-ncs during thermal treatment [9,10]. The inset shows time constants of PL decay.…”

Effect of the plasma composition on the structural and electronic properties of as-grown SiOx/Si heterolayers deposited by reactive sputtering

“…This fact has precluded the achievement of siliconbased optoelectronic systems for a long time. Over the last few years, several works have shown that it is possible to obtain light emission from silicon-based materials by doping with rare earth elements [1,2], low-dimensional [3,4] and stressed systems [5]. Another approach is through the synthesis of non-stoichiometric silicon dioxide [6][7][8][9].…”