The Influences of Surface Passivation on Luminescence Properties of Porous Silicon

By using n-butylamine as carbon resource,a layer of carbon film is covered on the parous silicon(PS)surface by means of radio frequency glow discharge.Raman spectra and IR spectra of the carbon film indicate that there are amino-groups and hydrogen atoms in the carbon film.IR spectra exhibits that the surface of the treated sample is mainly covered with Si-C,Si-N and Si-O.The influences of surface passivation of photoluminescence and electroluminescence properties of porous silicon have been presented.PL and EL spectra indicate that PL and EL intensity of the treated samples increase greatly and the blueshift of PL and EL peak compared with the samples without treatment and stable while storing in atmosphere.I～V characteristics reveal that the treated devices have a lower onset voltage.We present that the enhancement of the PL and EL intensity、stability and lower onset voltage of the treated sample is due to the existence of Si-C,Si-N and Si-O on the PS surface simultaneously,and blueshift of the PL and El peak are attributed to amino-groups and hydrogen atmos in the carbon film,As a result,carbon film passivation is a good way to enhance PS luminescent intensity and stability and improve the properties of PS devices.