11.12 A semiconductor possesses n donor levels, whose energy is 0 . A donor level can be...

11.12 A semiconductor possesses n donor levels, whose energy is

–ε0 . A donor level can be occupied either by a ‘spin up’ electron or a ‘spin down’ electron but it cannot be simultaneously occupied by two electrons. Obtain the grand partition function for the electrons in the donor levels and hence find the number of electrons in the donor levels.