Summary: | 碩士 === 中國文化大學 === 材料科學與奈米科技研究所 === 94 === In this study, the porous silicon (PS) films are fabricated by electrochemical anodization method. Various experimental parameters, such as etching current density, etching time and HF concentration, are investigated. Photoluminescence (PL), scanning electron microscope (SEM), energy dispersive spectrometer (EDS) mapping and Fourier transform infrared spectroscopy (FTIR) are used to analyze the film characteristics in the PS. N-type PS is difficult to form by conventional method for the lack of holes. However, with the forward biased P-N junction, sufficient holes can drift from P layer to N layer and hence the N-type PS can be easily formed. In addition, the thickness of P-type layer influences the etching result. From P-L spectrum, it can be found that etching on the N/P sample produces better PL emission and blue-shifting. Deep and straight shape pores can be obtained. The morphology, cross section view, porosity, PL and EDX analysis are investigated and compared with conventional method.
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