Optical and electrical characterization of sputter-deposited FeSi2 and its evolution with annealing temperature
Optical and electrical characterization of sputter-deposited FeSi2 and its evolution with annealing temperature
复制标题
溅射沉积 FeSi2 的光学和电学表征及其随退火温度的演变
DOI：
10.1063/1.2981198
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发表时间：
2008
影响因子：
3.2
通讯作者：
K. Pey
中科院分区：
文献类型：
--
作者：
K. Tan;D. Chi;K. Pey
研究了在p-Si（100）和SiO2/p-Si（100）衬底上化学沉积的FeSi_2薄膜的光学和电学性质及其随快速热退火（RTA）温度的变化。基于提出的双层和三层结构的光吸收模型，进行了光吸收测量，确定了FeSi 2的吸收光谱。一个直接的带隙行为的结论为非晶和多晶半导体FeSi 2。β-FeSi 2在1 eV时的吸收系数约为105 cm-1，带隙值约为0.86 eV。 在室温下的霍尔效应测量表明重掺杂和n型导电性的FeSi 2薄膜上的p-Si，其残留的载流子浓度被发现是密切相关的所观察到的带尾的亚带隙光吸收。载流子迁移率随RTA温度的升高而增大，并随残余载流子浓度的降低而减小。
Optical and electrical properties of sputter-deposited FeSi2 thin films on p-Si(100) and SiO2/p-Si(100) substrates as well as their evolution with rapid thermal annealing (RTA) temperature have been investigated. Optical absorption measurements were carried out to determine the absorption spectra of FeSi2 based on the proposed optical absorption model for the double-layer and triple-layer structures. A direct band gap behavior was concluded for both amorphous and polycrystalline semiconducting FeSi2. An absorption coefficient in the order of 105 cm−1 at 1 eV and a band gap value of ∼0.86 eV were obtained for the β-FeSi2. Hall effect measurements at room temperature indicate heavily doped and n-type conductivity for the FeSi2 films on p-Si, whose residual carrier concentration was found to be closely correlated with the observed subgap optical absorption via band tailing. The carrier mobility was shown to increase with decreasing residual carrier concentration when the RTA temperature was increased.