How does this annihilation process play in semiconductors? Initially i thought that as long as the an electron gets enough energy to move into conduction band (in an energy diagram) - it will move and wander within the Conduction band. However, i have a slide notes about annihilation that talks about recombination. How does this comes to play? - Does this means that although the electrons gets excited into Conduction Band - still there is some energy in the electron that will pull the electron back to Valence Band?