Modeling and Interface Engineering of Electrical Contacts

Highly conductive nanoscale electrical contacts suffer from strong current crowding and local hot spots due to nonuniform heat distribution, which severely affect the device properties. Here, we demonstrate a method to control the contact current distribution, by engineering the contact layer properties and geometry. From transmission line model calculations, we found that the contact current density greatly depends on the properties of the interfacial layer between two contacting members. The nonuniformity of the current distribution can be reduced significantly by strategically designing the interfacial layer specific contact resistivity p c . The acute current crowding in ohmic contacts can be reduced greatly by parabolically varying the p c along contact length, or by introducing a tunneling layer between the contact members. We also found that the current transport for 2D material based Schottky contacts can be improved by roughness engineering.