New experimental evidence for the role of long-range potential fluctuations in the mechanism of 1/f noise in a-Si:H

TL;DR

This study investigates 1/f resistance noise in amorphous silicon films with different doping and hydrogenation states, providing experimental evidence supporting the role of long-range Coulomb potential fluctuations caused by charged defects.

Contribution

It offers new experimental data confirming the theoretical model that attributes 1/f noise in a-Si to long-range Coulomb potential fluctuations from charged defects.

Findings

Spectra match theoretical predictions quantitatively

Long-range Coulomb fluctuations are significant in 1/f noise

Hydrogenation state influences noise characteristics

Abstract

We present measurements of 1/f resistance noise in three different films of amorphous silicon (a-Si) in the presense of a transverse electric current. Two of these films have n-i-n sandwich structure - in one of them all three layers were hydrogenated; in the other one only the n-layers were hydrogenated, while the intrinsic layer was deuterated. The third film had p-i-p structure with all three layers hydrogenated. The experimental spectra were found to be in a very good quantitative agreement with theoretical predictions, which were based on the mechanism involving long-range fluctuations of the Coulomb potential created by charged defects (see cond-mat/0210680).