Normal and anti Meyer-Neldel rule in conductivity of highly crystallized undoped microcrystalline silicon films

TL;DR

This study investigates the electrical conductivity of highly crystallized undoped microcrystalline silicon films, revealing the occurrence of both Meyer-Neldel rule and anti-Meyer-Neldel rule behaviors linked to microstructural variations.

Contribution

It demonstrates the coexistence of MNR and anti-MNR in microcrystalline silicon films and explains these phenomena through microstructure-dependent electronic transport mechanisms.

Findings

MNR observed in some films, anti-MNR in others

Microstructure influences the type of conductivity rule followed

Band tail transport explains the origin of MNR and anti-MNR

Abstract

We have studied the electrical conductivity behavior of highly crystallized undoped hydrogenated microcrystalline silicon films having different microstructures. The dark conductivity is seen to follow Meyer Neldel rule (MNR) in some films and anti MNR in others, which has been explained on the basis of variation in the film microstructure and the corresponding changes in the effective density of states distributions. A band tail transport and statistical shift of Fermi level are used to explain the origin of MNR as well as anti-MNR in our samples. The observation of MNR and anti MNR in electrical transport behavior of microcrystalline silicon is discussed in terms of the basic underlying physics of their origin and the significance of these relationships.