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φmEF φsEF
When contact is made, electrons flow from the metal into the empty states in the valence band. This results is a curvature of the bands upwards as the Fermi energy comes into equilibrium with the metal Fermi level.

labels > Depletion layer Energy barrier for holes labels EF EF > φs  − φm > Depletion layer Energy barrier for holes > Depletion layer Energy barrier for holes
When equilibrium is reached, there is a region which has been depleted of holes, and a energy barrier for holes to reach the interface with the metal and recombine with an electron there.