  Recently, new quantum features have been studied in the area of ridged
quantum wells (RQW). Periodic ridges on the surface of the quantum well layer
impose additional boundary conditions on the electron wave function and reduce
the quantum state density. Electrons, rejected from forbidden quantum states,
have to occupy the states with higher energy. As a result, Fermi energy in RQW
increases and work function (WF) decreases. We investigate low WF electrode,
com-posed from a metal RQW layer and a base substrate. The substrate material
was selected so that electrons were confined to the RQW. The WF value depends
on ridge geometry and electron confinement. We calculate WF in the metal RQW
films grown both on a semiconductor and metal substrates. In the case of
semiconductor substrate, wide band gap materials are preferable as they allow
more reduction in RQW work function. In the case of metal substrate, low Fermi
energy materials are preferable. For most material pairs, the WF was reduced
dramatically. Such structures, can serve as electrodes for room temperature
thermionic and thermotunnel energy converters and coolers.
