Example 1 : Angle-Dependent Analysis

Example 1 : Angle-Dependent Analysis of a Silicon Wafer with a Native Oxide Surface Layer

A series of Si 2p photoelectron spectra recorded for emission angles of 10-90º to the surface plane. Note how the Si 2p peak of the oxide (BE ~ 103 eV) increases markedly in intensity at grazing emission angles whilst the peak from the underlying elemental silicon (BE ~ 99 eV) dominates the spectrum at near-normal emission angles.

(courtesy of Physical Electronics, Inc. (PHI))

Note : in this instance the emission angle is measured with respect to the surface plane (i.e. 90º corresponds to photoelectrons departing with a trajectory normal to the surface, whilst 10º corresponds to emission at a very grazing angle;