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.