Understanding and controlling heterojunction band discontinuities

We discuss two recent results on the microscopic nature and control of the band lineup at semiconductor–semiconductor interfaces. First, we identified a correlation between measured heterojunction band discontinuities and Schottky barrier heights of the corresponding semiconductors, as predicted by several theoretical models. Second, we found that ultrathin metal intralayers modify the band lineup of polar interfaces by several tenths of an electron volt. At least in principle, this degree of freedom can be exploited to tailor heterojunction devices.