The electron energy spectrum and thermionic device efficiency

The influence of the electron energy spectrum of solid-state thermionic devices on electronic efficiency is analyzed. Calculations are performed on both single and multibarrier GaAs/AlGaAs and InGaAs/InAlAs systems. Analysis reveals a wide barrier is desirable for single-barrier thermionic devices due to the associated sharpness in the electron energy spectrum. It is also shown that high electronic efficiency may be achieved in multibarrier thermionic devices consisting of thin barriers, which would separately give low efficiency, but together can be arranged to produce a desirable electron energy spectrum.