Quantitative Imaging of Sheet Resistance with a Scanning Near-Field Microwave Microscope

TL;DR

This paper presents a rapid, quantitative method for imaging the sheet resistance of metallic thin films using a scanning near-field microwave microscope, enabling high-resolution, fast measurements across a broad frequency range.

Contribution

It introduces a novel technique for quantitative sheet resistance imaging with high speed and sensitivity, applicable to various thin film materials.

Findings

Achieves 10 ms per pixel imaging speed.

Resolves sheet resistance changes as small as 0.6 Ohms/sq.

Successfully images YBCO thin film on sapphire at 7.5 GHz.

Abstract

We describe quantitative imaging of the sheet resistance of metallic thin films by monitoring frequency shift and quality factor in a resonant scanning near-field microwave microscope. This technique allows fast acquisition of images at approximately 10 ms per pixel over a frequency range from 0.1 to 50 GHz. In its current configuration, the system can resolve changes in sheet resistance as small as 0.6 Ohms/sq for 100 Ohms/sq films. We demonstrate its use at 7.5 GHz by generating a quantitative sheet resistance image of a YBa2Cu3O7 (YBCO) thin film on a 5 cm-diameter sapphire wafer.