论文部分内容阅读
Ge材料中n型杂质激活的电子浓度偏低,以及费米能级钉扎效应导致的金属与n型Ge接触电子势垒高度偏大,使金属与n型Ge接触电阻较大。基于Ge的材料特性,分析了缺陷对杂质浓度以及费米能级钉扎对电子势垒高度的影响;综述了提高Ge材料中n型掺杂电子浓度的方法,如激光退火、磷和锑共掺、循环离子注入/退火、氟钝化等;讨论了降低金属与n型Ge接触电子势垒高度的途径,即插入薄的界面层形成金属-界面层-Ge接触。电子浓度的提高,以及电子势垒高度的降低,有效地减小了金属与n型Ge接触电阻。
The electron density of n-type impurity in Ge material is low, and the contact electron barrier between metal and n-type Ge caused by Fermi level pinning effect is too large, which makes the contact resistance between metal and n-type Ge larger. Based on the properties of Ge materials, the effects of defects on the impurity concentration and Fermi level pinning on the electron barrier height were analyzed. The methods to improve the n-type doping electron concentration in Ge were reviewed, such as laser annealing, phosphorus and antimony Doping, cyclic ion implantation / annealing and fluorine passivation. The way of reducing the height of the contact electron barrier between the metal and the n-type Ge is discussed. That is, a thin interfacial layer is formed to form a metal-interface layer-Ge contact. The increase of the electron concentration and the decrease of the height of the electron barrier effectively reduce the contact resistance between the metal and the n-type Ge.