纳米稀土-介质薄膜光电发射光谱和能带结构

用真空蒸发沉积的方法制备了纳米稀土(La、Nd、Sm)粒子 BaO介质薄膜.研究表明薄膜的光电发射光谱响应阈值受纳米稀土粒子形状和大小的影响,球形纳米稀土(Sm)粒子 BaO介质薄膜的光谱响应阈值波长为720 nm,条状纳米稀土(La和Nd)粒子 BaO介质薄膜阈值波长分别为650 nm和660 nm.研究得到纳米稀土粒子 介质薄膜等效界面位垒高度在1.7～2.0 eV之间.由于纳米稀土粒子与BaO介质各自逸出功不同,当构成薄膜后使得纳米粒子周围的空间电荷分布发生变化,纳米粒子周围的能带发生弯曲.

Photoemission Photospectrum and Energy Band Structure of anoparticle Rare Earth Composite Thin Films

The nanoparticle rare earth (La、Nd、Sm) BaO composite thin films were deposited through vacuum evaporation.The shape and size of the nanoparticles of the rare earth affect the photoemission photospectral response threshold of the thin films.The threshold wavelength of the photospectral response of the thin film,in which the rare earth (Sm) nanoparticle shape was sphere,was 720 nm.The threshold wavelengths of the photospectral response of the thin films,in which the rare earth (La and Nd) nanoparticles shape was long,were 650 nm and 660 nm,respectively.We obtained that the equivalent barrier around rare earth nanoparticle was 1.7～2.0 eV.Because the work functions of rare earth nanoparticles and BaO composite are different,the spatial electron distribution around the rare earth nanoparticles is changed in the composite thin films.Then the energy bands around the rare earth nanoparticles become curved.