Temperature and doping dependence of non-Gaussian noise and noise statistics in hydrogenated amorphous silicon

Coplanar conductance fluctuations in hydrogenated amorphous silicon have been measured as a function of doping type and temperature and are found to have an inverse frequency (Formula presented) spectral density. The (Formula presented) noise statistics are non-Gaussian as reflected by (i) strong correlations of the noise power across frequency space and (ii) a power-law second spectrum. The (Formula presented) noise and (Formula presented) noise statistics exhibit weak doping and temperature dependences. The results are discussed in terms of a model for electronic conduction involving inhomogeneous current filaments whose conductance is modulated by hydrogen diffusion. The growth of the frequency correlation coefficients with averaging time, the variation of the magnitudes of the correlation coefficients with the magnitudes of the second spectrum, and the scaling properties of the second spectra are consistent with the presence of hierarchical kinetics.