Spectral analysis of adsorbate induced field-emission flicker noise

Spectral analysis of field-emission flicker noise is developed for a probe current originating from a portion of a single (hkl) plane of the emitter. The current noise is related to equilibrium absorbate density fluctuations in the probed region with the total number of net plane adatoms constant. The noise spectrum factors as S(ω)=S_∞(ω)+S_B(ω) when the finite size of the net plane is accounted for. The spectrum due to unbounded diffusion S_∞(ω) is proportional to one derived in Burgess’s model of semiconductor contact noise. The boundary-effect contribution S_B(ω) increases dS(ω)/dω at low frequency, whereas anisotropic diffusion decreases it.