纳米硅镶嵌氮化硅薄膜的制备及非线性光学性质研究

The preparation and nonlinear optical properties of nc-Si/SiN_x composite films

采用射频磁控反应溅射法结合热退火处理技术制备纳米硅镶嵌氮化硅(nc-Si/SiNx)复合薄膜。通过X射线能谱(EDS)、红外光谱(IR)、X射线衍射(XRD)及紫外-可见吸收光谱(UV-vis)的测定,对薄膜进行了组分、键合状态、结构及光学带隙的表征。采用皮秒激光运用单光束Z扫描技术开展了对该复合薄膜的非线性光学性质的研究,测得其三阶非线性折射率系数和非线性光吸收系数分别为10-8esu和10-8m/W量级,并将薄膜这种三阶光学非线性增强的原因归因于量子限域效应。

The nanoscale-Si-particle embedded in silicon nitride（nc-Si/SiNx）composite films were prepared by r. f. magnetron reaction sputtering technique and thermal annealing. The composition, structure, bond formation and optical band gap of the films were characterized by energy dispersive spectrometer（EDS）, infrared spectroscopy （IR）,X-ray diffraction（XRD） and ultraviolet-visible absorption spectroscopy（UV-vis）. The nonlinear optical properties of nc-Si/SiNx composite films were investigated by using single beam Z-scan technique with a picosecond pulses laser. The measured thirdorder nonlinear optical refractive index and nonlinear absorption coefficient were enhanced and estimated to be on the order of 10^-8esu and 10^-8m/W respectively. This was due to the quantum confinement effect.