This discovery of the light emission of porous silicon(PS) has led to much excitement at the prospect of developing Si based optoelectronic devices.However

the Si-H species

which are the passivation of the freshly prepared PS

are unstable

therefore the peak wavelength and efficiency of the luminescence is extremely sensitive to the preparation conditions and subsequent treatment of the sample

which has disturbing consequences for the suitability of this material for device applications.The growth of a high quality oxide around the surface of the Si crystals has been suggested as an alternative method of the PS surface passivation.Some progresses such as anodic oxidation

rapid thermal oxidation(RTO)

hot water treatment and so on have been reported for the preparation of oxidized PS.In general

oxidation has a detrimental effect on the photoluminescence(PL) efficiency.SC-1(NH

3

H

2

O/H

2

O

2

/H

2

O

1:1:5

V/V

) and SC-2(HCl/H

2

O

2

/H

2

O

1:1:6) solutions are two stan-dard oxidant and clean reagent and have been utilized in the traditional silicon semiconductor industry for many decades.In this work

we exploited these two novel oxidant solutions to the preparation of oxidized PS.The characteristic of the oxidized PSprepared by oxidizing the freshly prepared PSin the solutions of SC-1 and SC-2 have been studied by comparing with those prepared by thermal oxidization and those oxidized by other oxidants

such as HNO

3

and H

2

SO

4

.It has been shown that SC-1 is an efficient oxidant for the preparation of oxidized PS with an intense PLand a simple and stable surface composition.The oxidized PSprepared in SC-1 for 30 s and then in SC-2 for 4 min has a more stable PLthan that from the sample oxidized in only SC-2.It means a stable surface composition is very important for the stable PL.