采用磁控溅射技术,在Si(100)衬底上制备了一系列不同周期、不同Ge层厚度的Ge/Si多层膜样品。用室温光致发光(PL)、Raman散射和AFM图谱对样品进行表征。结果表明:Ge/Si多层膜中的PL发光峰主要来自于Ge晶粒,并且Ge晶粒生长的均匀性对PL发光影响较大,生长均匀的Ge晶粒中量子限域效应明显,随着晶粒的减小,PL发光主峰发生蓝移;在Ge晶粒均匀性较差时,PL发光峰强度较弱,量子限域效应不明显。
The series of Ge/Si multilayer films have been prepared by magnetron sputtering on c-Si(100) substrates at different periods and Ge thickness. Room-temperature photoluminescence spectra, Raman scattering spectra and AFM image were carried out in order to investigate the quliity of the samples. The results indicate that the emission peak of PL comes from the Ge crystal grains in the Ge/Si multilayer. And the uniformity of the Ge crystal grains has great influence on the PL. When the Ge crystal grains are uniform, quantum confinement effect is strong. The blue shift of PL band position takes place as the Ge crystal grains become smaller. When the Ge crystal grains are not uniform, the weak emission peak intensity of PL is observed, and the quantum confinement effect in the Ge crystal grain is unconspicuous.