Conductance Fluctuations in Hydrogenated Amorphous Silicon
Abstract
Measurements of coplanar resistance fluctuations are reported for ntype doped hydrogenated amorphous silicon over the temperature range 190 < T < 450 K. The spectral density of the fluctuations obey a 1/f frequency dependence over the frequency range 1 < f < 10^3 Hz. The noise power displays a nonlinear dependence on the applied DC current, that is the noise power S _{I} ~ I^{rm b}, where 1.0 < b < 2.5. Random telegraph switching noise is observed with fluctuations as large as deltaR/R ~ 10^{2} in samples with volumes of 10^{7} cm^3. Statistical analysis of the noise power spectra show the fluctuations to be strongly nonGaussian. The noise power magnitude and frequency dependence are both time dependent. These results suggest that cooperative dynamics govern the conductance fluctuations, and are discussed in terms of models for noise in composite and inhomogeneous materials.
 Publication:

Ph.D. Thesis
 Pub Date:
 January 1992
 Bibcode:
 1992PhDT........95P
 Keywords:

 NOISE;
 Physics: Condensed Matter; Engineering: Materials Science