Stabilization of luminous properties of porous silicon by vacuum annealing at high temperatures

Strong enhancement and long-time stabilization of porous silicon photoluminescence by laser irradiation

“…It has been clear by FT-IR spectroscopy that the PS surface oxidation caused by the laser heating effect significantly progresses during laser irradiation. A gradual decrease in PL intensity during laser exposure has been observed in the case of our PL measurement after 30 days of aging and the degradation in PL strength by UV irradiation has also been reported by other research groups [3,4]. This will necessitate a further examination under various conditions of sample preparation and laser irradiation for determination of ideal effective conditions.…”

“…As for the surface oxidation of PS, the thermal annealing effect has been investigated at various temperatures [2][3][4][5]. Tsai PS due to presence of oxygen atoms after the removal of Si-H x (x ¼ 1-3) species during annealing increases the PL intensity.…”

“…The incorporation of a stable and efficient luminescent PS element into a microelectronic circuit encourages the possibility of commercial applications significantly. Regarding the PL of PS layers, thermal annealing treatments have been demonstrated to achieve strong and stable PL intensity [2][3][4][5]. Further the laser heating effect similar to the annealing has been introduced [6][7][8].…”

Stabilisation of surface and photoluminescent properties of porous silicon

“…These processes are associated with adsorption of hydrogen or Si-H x complexes (x = 1, 2, 3) which determine concentration of nonradiative recombination centres (broken bonds of silicon) [6,7], or with oxidation of silicon pore walls. The most important results on stabilisation of the luminescent properties of PS have been obtained using inactivation of the broken bonds of silicon, fast oxidation, and modification of electrolyte which forms the PS [8][9][10]. The common feature of these methods for stabilising the surface of PS is substitution of unstable complexes Si-H x (x = 1, 2, 3) with more stable Si-O ones.…”

Effect of Post-processing on Photoluminescence and Surface Composition of Porous Silicon

“…The luminous intensity and efficiency of PS are significantly decreased after a period of storage because of its instability when it is used as a light emitting material, or its surface covered with relatively small holes prompts the reduction of the efficiency adsorption and sensitivity of PS which applied as a sensor. Therefore, in order to solve these problems, PS should be post-processing, such as surface oxidation [13,14], surface passivation [15][16][17][18], ion implantation [19], organic compound [20] and solution erosion [21], and many others [22,23].…”