高温氧化多孔硅的电子束辐照效应

通过高温氧化处理得到的多孔硅,其阴极射线发光谱呈现明显的三峰结构。峰强随电子束辐照时间而下降。对光致发光很弱的样品,电子束辐照后光致发光明显地增强。红外透射谱及Raman谱分析表明样品基本上成为SiO_x.进一步分析指出三峰可能来源于SiO_x中的缺陷中心发光。电子束辐照在SiO_x禁带中引进了一些缺陷能级,通过这些能级使得紫外线可激发样品发光,出现光致发光增强的现象。

EFFECT OF ELECTRON IRRADIATION ON HIGH TEMPERATURE OXIDIZED POROUS SILICON

igh temperature oxidized porous silicon has been investigated.Three peaks can be seen on the cathodeluminescent(CL)spectrum.The intensity of these peaks decreases fast with electron irradiation.For poor photoluminescent(PL)sample,the PL intensity enhances obviously after electron irradiation.The IR and Raman spectra of high temperature oxidized porous silicon show that whose strueture is mainly SiOx.Further analysis shows that three peaks may come from the luminescence of defect centers in SiOx.As electron irradiation,some other defects are generated in SiOx.This makes the CL intensity decrease and only through these defects the luminescent centers can be excited by UV light,therefore the sample's PL intensity is increased.