Characterization of deep-hole structure of semiconductor devices using transmission small-angle X-ray scattering

In order to realize non-destructive cross-sectional profile measurement for deep hole advanced devices, we have applied a transmission small angle X-ray scattering instrument that employs a Mo-target X-ray source and a high-sensitivity two-dimensional detector. It enables us to measure the average cross-sectional profile of periodic hole patterns that are several tens of nanometers in diameter and several micrometers in depth. The structure, characterized by hole diameter, tilt angle, and ellipticity as functions of depth, was successfully evaluated. The obtained average depth profile of the holes was compared with that from a cross-sectional SEM and a milling SEM, and it was confirmed that they agreed very well.