【摘要】 采用一种新颖而简便的方法,改善多孔硅的发光特性。该方法包括酸处理和阴极还原两步。实验证明通过对多孔硅进行酸处理,能有效提高多孔硅的发光强度;通过对多孔硅进行阴极还原处理,能明显改善多孔硅的发光稳定性,而且发光强度也得到了提高。综合酸处理和阴极还原两技术的特点,对所制备的多孔硅立即先进行酸处理,然后再对其进行阴极还原处理,结果表明该方法能较好地提高多孔硅的发光效率和发光稳定性。而且还对其发光机制进行了探讨。更多还原

【Abstract】 Silicon is a traditional semiconduction material, as we all know, and has a broad use in semiconduction industry. But because of its indirect bandgap and rather low light effiency, silicon had not been treated in application in optoelectronic material making process. In 1990, Canham published that porous silicon sample fabricated by electrochemical anodization etch possesses has very intense photoluminescence(PL)emission, and its light efficiency can campare to direct bandgap material GaAs. This report gave a new means to realize Si-based emitting material of photoelectricity integration.The investigation on photoluminescence properties of porous silicon samples made through conventional electrochemical anodization method under different conditions was reported. Two different ways have been used to treat porous silicon samples, including cathodic reduction process and acid treatment. Moreover, we mainly focus on contrast of photoluminescence properties of treated porous silicon samples by two different ways, comparing and analyzing the photoluminescence spectra of different samples. Experimental results indicate that through nitric acid treatment, an increase in luminous intensity of porous silicon can been seen, and the effect is related to nitric acid concentration. The photoluminescence will be enhanced with the nitric acid concentration increasing. Compared with other acids, nitric acid treatment can effectively increase the luminescence intensity of porous silicon and make the luminescence stability of porous silicon better. The results also prove that the process of cathodic reduction can obviously improve luminescence stability of porous silicon and luminescence intensity as well. In this experiment, we found that aging time play a comparative important role in final experimental result. The results showed that the two methods can effectively enhance luminescence efficiency and stability. Moreover, we firstly processed cathodic reduction, then nitric acid treatment, giving a comparsion between the effect of these two methods. A conclusion can be drawn that the method of firstly processed porous silicon samples with nitric acid treatment and secondly cathodic reduction treatment has better effect to porous silicon luminescence intensity and stability than that of firstly cathodic reduction treatment and secondly nitric acid treatment. In addition, we further discussed the possible luminescence model of porous silicon.更多还原