Abstract
The precise definition and meaning of single electrode potentials is discussed. This definition is then used to derive an expression for the flat-band voltage of electrolyte/oxide/silicon (EOS) structures. The same reasoning also produces an expression for the flat-band voltage of MOS capacitors, which includes dipole interaction terms. The difference in flat-band voltage between EOS and MOS structures on the same wafer involves the potential of the reference electrode and the work function of the gate metal. Experiments were performed with aluminum as gate metal, and a saturated calomel reference electrode. In these circumstances, ΔVFB is determined as 0.86±0.03 V. This value can then be used to derive the single electrode potential of the normalized hydrogen electrode. The result is ENHE = 4.74 V, in very good agreement with other recent determinations.