Large Grain Size Dependence of Resistance of Polycrystalline Films

TL;DR

This paper extends Volger's model to qualitatively analyze how grain size affects the electrical resistance of polycrystalline films, providing a way to infer growth direction from resistance measurements.

Contribution

It introduces a simplified model linking grain size growth with resistance variation, enabling identification of growth direction in polycrystalline films.

Findings

Resistance varies with grain size in a predictable manner.

Curves can identify growth direction from resistance data.

Model aligns with experimental observations.

Abstract

A qualitative behavior of grain size dependent resistance of polycrystalline films has been worked out by extending the earlier model (Volger's model) for polycrystalline films. Growth of grain size is considered to be accompanied with a decrease in the number of grains present. The variation of the number of grains is restricted along one direction at a time, assuming it to be constant along the other two directions, to simplify the problem. Combining the results along film thickness and film length, the calculated resistance versus grain size shows a family of curves. These curves can be used to know the growth direction by comparing the measured grain size dependence of the resistance.