Mott-Schottky rule

FIGURE 2.4.2 (a) Simple band line-up diagram for a metal-organic semiconductor interface assuming that the Mott-Schottky rule holds and that the vacuum levels for the metal and semiconductor are aligned, (b) Application of a positive bias to the metal can result in hole injection into the semiconductor by thermionic emission over the barrier, (c) Band line-up diagram in the case where an interface dipole is present, causing a shift (A) in the vacuum levels across the junction. 

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