肖特基接触的机理及不均匀性研究

对一般情况下肖特基接触的机理和肖特基势垒高度的影响因素做了系统分析,研究了肖特基接触特性的不均匀性及其原因,指出多晶界面势垒高度比同种材料的要低。通过实验,研究了金属/n-poly-Si0.83Ge0.17肖特基结的I-V-T特性,得到了势垒高度及影响因子与测试温度和外加偏压的依赖关系。研究发现:随着测试温度升高,表观理想因子变小,肖特基势垒高度变大;外加偏压增大,表观势垒高度和理想因子均变大。基于肖特基接触的不均匀性进行建模,得到了退火样品的表观势垒高度和理想因子近似为线性负相关的结论。

Investigation on Physical Mechanism and Inhomogeneity of Schottky Contact Properties

Mechanism of Schottky contact and influencing factors on Schottky barrier height (SBH) were analyzed systematically under general circumstance. The inhomogeneity of Schottky contact as well as its causes were studied. SBH value measured at polycrystalline interface is always lower than that at monocrystalline interface for the same material. By studying the I-V-T properties of metal/n-poly-Si0.83Ge0.17 Schottky junction samples, the dependence of apparent SBH and ideality factor on testing temperature as well as external bias were obtained. It has been found that with increase of testing temperature, ideality factor decrease while SBH increases. Meanwhile external bias increases will lead to both the apparent SBH and ideality factor become larger. Based on the model of inhomogeneous distribution of Schottky contact, it has been drawn a conclusion that apparent SBHs of the annealed samples have a nearly linear correlation with their corresponding ideality factors.