Si基热氧化Si_(1-x-y)Ge_xC_y薄膜的室温光致发光特性

Room\|Temperature Photoluminescence of Thermally Oxidized Si_(1-x-y)Ge_xC_y Thin Films on Si (100) Substrates\+*

采用等离子体增强化学气相淀积 ( PECVD)法在 Si( 1 0 0 )衬底上淀积一层厚度约为1 70 nm的富 Ge高 C含量的 Si1- x- y Gex Cy 薄膜 ,然后将其分别在 80 0℃和 1 1 0 0℃下湿氧氧化2 0 min.在室温下观测到强烈的光致发光 .室温下的光致发光谱 ( PL谱 )测量显示 ,80 0℃下氧化后的样品在 370 nm和 396nm附近有两个光致发光带 ,1 1 0 0℃下氧化后的样品只在 396nm附近有一个光致发光带 .396nm附近的发光带可归之于由氧化薄膜中的缺陷 O- Si- O ( Si02 )或 O- Ge-O( Ge02 )引起的 ,而 370 nm附近的发光带与薄膜中 Ge-

Intensive photoluminescence of thermally oxidized Si 1- x-y Ge x C y thin films on Si(100) substrates are first observed at room temperature. The Si 1-x-y Ge x C y thin films rich in Ge and C content are grown on Si substrate by Plasma Enhanced Chemical Vapor Deposition (PECVD) and then wet oxidized for 20 minutes at 800℃ and 1100℃ respectively. Photoluminescence spectra of the samples are measured at room temperature and under 250nm excitation. Two photoluminescence bands with the peaks at ~370nm and 396nm are observed in the 800℃ oxidized samples, and only one photoluminescence centered at ~396nm are observed in the 1100℃ oxidized samples. The 396nm band is attributed to the defects O\|Si\|O or O\|Ge\|O in the oxidized films, while the 370nm band is consistent to C in the films.