Dear Student
The barrier height is defined as the potential difference between the Fermi energy of the metal and the band edge where the majority carrier reside. while in semiconductor physics, the depletion region, also called depletion layer, depletion zone, junction region, space charge region or space charge layer, is an insulating region within a conductive, doped semiconductor material where the mobile charge carriers have been diffused away, and its width is called width of depletion region.
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