Either an ohmic contact or a Schottky barrier is formed when a metal and an n-type semiconductor are brought into contact. In the ideal case, the magnitude of the band bending ${\displaystyle V_{bi}}$ and contact resistance depend on the doping of the semiconductor, its dielectric constant and the Schottky barrier ${\displaystyle \phi _{B}=\phi _{M}-\chi _{S}}$ where ${\displaystyle \phi _{M}}$ is the work function of the metal and ${\displaystyle \chi _{S}}$ is the electron affinity of the n-type semiconductor.