| With the development of microelectronic industry, the integration of transistor in integrated circuit increases continuously. However, the traditional electrical interconnection becomes a bottleneck of the development of the microelectronic industry due to increase of power consumption, heat transfers, transport delay, and so on. Optical interconnection which uses photons instead of electrons to transform information is considered to be an effective solution. And thus, achieving efficient silicon-based light source compatible with the current IC manufacturing technique has become a key point. The near-infrared luminescence of Er3+(1.54 μm) corresponds to the low-loss window of silica-based optical fiber communication. Moreover, the fabrication of erbium-based device is compatible with CMOS technique. Thus, the erbium-doped silicon-based material become one of the promising candidates for Si-based light source and has hence been studied extensively.In this thesis, silicon-rich silicon oxide (SRO) films with different doping content of erbium have been fabricated by electron beam evaporation. Abundant amount of stable luminescence centers (LCs) have been introduced into the Er-doped silicon-rich silicon oxide (SROEr) films. We have investigated the LCs-sensitized luminescence of Er3+ in the SROEr film and the temperature dependence of Er3+ luminescence. Comparing different annealing methods, we have optimized the Er3+ emission with high-concentration dopant, and got the condition required for the precipitation of erbium silicate. Moreover, we have studied the optical properties of different crystalline structure of erbium disilicate and the sensitized luminescence of erbium silicate. The primary results are summarized as follows:(1) Luminescence centers in the SROEr films with low excess silicon content evolve with the annealing temperature from 500℃ to 900℃. And sensitized erbium luminescence has been observed for each annealing temperature while the optimum annealing temperature is at 900℃.(2) Through comparing the derived excitation rate of Er3+ and doping content, we have semiquantitatively confirmed that, compared with silicon nanocrystals, the luminescence centers with atomic size have better sensitization effect on Er3+ in SROEr films when the annealing temperature is lower than 1100 ℃. The study of temperature dependent photoluminescence of 900℃-annealed films have confirmed that the luminescence center sensitized Er3+ emission has favourable temperature stability and is involved in a phonon-assisted energy transfer process.(3) When the doping concentration of Er3+ reaches 1021 cm-3, the rapid thermal annealing (RTA) can increase the amount of optical active Er3+ due to the rising of temperature. Moreover, compared with conventional thermal annealing, RTA retained more luminescence centers which contribute to the PL of heavily doped Er3+ ions. However, conventional thermal annealing for 2 hours leads to the precipitation of erbium silicate (Er2Si2O7) crystalline. Meanwhile, the nc-Si precipitation may have the inducement effect of the precipitation of erbium silicate.(4) Layered erbium silicate (Er2Si2O7) films have been fabricated by EBE. It is found that the crystal structures are y-phase and a-phase when the annealing temperature is 1100℃ and 1150℃, respectively. It has been found that y-Er2Si2O7 has better optical property than α-Er2Si2O7.(5) Compared with the film without Si thin layers, it is found that the introduce of Si thin layers significantly enhances the luminescence of erbium silicate, which demonstrates the sensitization effect of Si thin layers. However, the decrease of erbium content restrains the formation of layered erbium silicate, and leads to the formation of α-Er2Si2O7, which is not good for sensitized luminescence of erbium silicate. |
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