A near-field scanned microwave probe for spatially localized electrical metrology

TL;DR

This paper introduces a highly localized near-field microwave probe with a 10-micron sampling volume, enabling precise, non-invasive electrical measurements for applications like semiconductor wafer analysis.

Contribution

The paper presents the development of the smallest near-field microwave probe to date, with a 10-micron sampling volume, improving spatial resolution in electrical metrology.

Findings

Achieved a 10-micron sampling volume in microwave microscopy.

The probe's response is confined to the sampling volume, independent of outside sample properties.

The probe is suitable for non-contact, localized electrical measurements in semiconductor manufacturing.

Abstract

We have developed a near-field scanned microwave probe with a sampling volume of approximately 10 micron in diameter, which is the smallest one achieved in near-field microwave microscopy. This volume is defined to confine close to 100 percent of the probe net sampling reactive energy, thus making the response virtually independent on the sample properties outside of this region. The probe is formed by a 4 GHz balanced stripline resonator with a few-micron tip size. It provides non-contact, non-invasive measurement and is uniquely suited for spatially localized electrical metrology applications, e.g. on semiconductor production wafers.