3D FinFET metrology (LEXES)

3D FinFET metrology with EX-300 LEXES Shallow Probe
Based on the field-proven Low energy Electron induced X-ray Emission Spectrometry technique (LEXES) developed by CAMECA over the past 15 years, the EX-300 Shallow Probe is a versatile metrology tool capable of supporting innovation at 14nm node and beyond, and the most appropriate candidate for characterizing novel 3D structure devices such as P/As in n-FET and Ge/B in p-FET. It supports metrology engineers in their critical choices and ensures smooth ramping-up of N14/N10/N7 new process integration and consequent volume production monitoring.

A non-destructive in-line technique enabling real device monitoring

By combining a vertical non-destructive small electron beam (down to 20µm), insensitive to the structure geometry and a fully automated interface, LEXES can directly measure in OCD (SCD) pads and in-line monitor product wafers.

Unlike other x-ray metrology techniques such as XRD, XRR or XRF that require planar structures with larger dimensions to enable proper data output, LEXES is capable of directly measuring the dose in 3D FinFET without any further ambiguous data processing. This advanced metrology tool can control variations from 3D-pad to 3D-pad (yield optimization) as well as from wafer to wafer (in-line control).

Furthermore, CAMECA has optimized the EX-300 Shallow Probe in order to achieve excellent precision for light element detection, particularly for B (p-FET) where XRF and XPS are nearly blind, as well as for P low dose levels (n-FET) where XRD is not sensitive. By finely tuning the probing energy, the LEXES-based EX-300 is uniquely able to detect composition variations, in a contactless manner, from the top to the bottom of the Fins.

With its capacity to perform measurements within the 3D pads, the EX-300 brings substantial added value to composition metrology because the relationship between planar pad and 3D structure is not straightforward due to large loading effects.

Robust front-end metrology to ensure high yields in new and coming process nodes

The Shallow Probe is a fully automated, fab-compliant tool capable of securing continuous monitoring of the chosen critical parameters in planar or 3D structures. It will adjust all recipes to the multiple product design choices. Combining flexibility with robustness, the Shallow Probe provides process and metrology engineers with the essential information needed to easily detect dopant and address chemical composition issues at the front-end.
Today, the Shallow Probe is the most robust metrology partner for FinFET technology development, clearly leading the way in product monitoring of next generation 3D devices.