Er

3+

photoluminescence(PL) in silicon-based materials has been attracting much interest because of its potential application in Si-based optoelectronic devices.Er

3+

ions can be doped into different hosts

such as crystalline silicon

hydrogenated amorphous silicon suboxide(a-SiO

x

:H)

SiO

2

film containing Si nanocrystals and so on.In this report PLproperties of undoped and Er

3+

-doped SiO

x

films containing amorphous Si nanoparticles were studied.a-SiO

x

films containing Si nanoparticles were prepared by plasma enhanced chemical vapor deposition(PECVD) using a gas source with mixture of SiH

4

and N

2

O.Erbium ions were implanted into as-deposed SiO

x

films at 500 keV with a varying dose range of(1~3)10

15

/cm

2

and then annealed at 300~900 ℃ for 30 s under N

2

.Visible PLexperiments were performed with a Dilor XY-800 triple grating spectrometer with a charge-coupled device(CCD) detector.The samples were excited by 514.5 nm line of Ar

+

laser.The Er

3+

infrared PLspectra were measured using FTIR spectrometer(Bruker IFS

120

HR).The wavelength of Ar

+

(laser) is 514.5 m and the nominal laser power was 200 mW.The results showed that the PLintensity from nc-Si in SiO

2

at 750 nm is one order of magnitude stronger than that from amorphous silicon clusters in a-SiO

x

:H

and the PLintensity from Er

3+

at 1.54 m in Er doped a-SiO

x

:His a factor of 4 higher than that in Er doped SiO

2

.The PLand crystallinity of a-SiO

x

:Has function of annealing temperature were also studied.In combination with the Raman measurement

the results show that photoluminescence from amorphous Si nanoparticles also follows the quantum confinement model as in Si-nanocrystals.Our study indicates that a competitive relationship between the light emissions of a-Si clusters and Er

3+

in the Er-doped a-SiO

x

:Hfilm is also present and the films yield efficient Er

3+

emission even superior to that of Er doped SiO

2

containing Si nanocrystals

suggesting a-Si clusters can also act as both the Absorbing medium and sensitizer in Er

3+

excitation as nc-Si in Er doped SiO

2

.Er

3+

emission intensity does not depend strongly upon whether it is nc-Si or a-Si clusters.These results presented here open up a route towards the fabrication of efficient Si-based light-emitting devices.