Kla Tencor Corporation

Kla Corporation

Sergey Zalubovsky

Antonio Arion Gellineau

John Josef Hench

Thaddeus Gerard Dziura

Andrei Veldman

Andrei V Shchegrov

Methods and systems for characterizing dimensions and material properties of semiconductor devices by full beam x-ray scatterometry are described herein. A full beam x-ray scatterometry measurement involves illuminating a sample with an X-ray beam and detecting the intensities of the resulting zero diffraction order and higher diffraction orders simultaneously for one or more angles of incidence relative to the sample. The simultaneous measurement of the direct beam and the scattered orders enables high throughput measurements with improved accuracy. The full beam x-ray scatterometry system includes one or more photon counting detectors with high dynamic range and thick, highly absorptive crystal substrates that absorb the direct beam with minimal parasitic backscattering. In other aspects, model based measurements are performed based on the zero diffraction order beam, and measurement performance of the full beam x-ray scatterometry system is estimated and controlled based on properties of the measured zero order beam.

Full beam metrology for x-ray scatterometry systems

Methods and systems for characterizing dimensions and material properties of semiconductor devices by transmission small angle x-ray scatterometry (TSAXS) systems having relatively small tool footprint are described herein. The methods and systems described herein enable Q space resolution adequate for metrology of semiconductor structures with reduced optical path length. In general, the x-ray beam is focused closer to the wafer surface for relatively small targets and closer to the detector for relatively large targets. In some embodiments, a high resolution detector with small point spread function (PSF) is employed to mitigate detector PSF limits on achievable Q resolution. In some embodiments, the detector locates an incident photon with sub-pixel accuracy by determining the centroid of a cloud of electrons stimulated by the photon conversion event. In some embodiments, the detector resolves one or more x-ray photon energies in addition to location of incidence.

Transmission small-angle X-ray scattering metrology system

Full beam metrology for X-ray scatterometry systems

Methods and systems for realizing a high brightness, liquid based x-ray source suitable for high throughput x-ray metrology are presented herein. A high brightness x-ray source is produced by bombarding a rotating liquid metal anode material with a stream of electrons to generate x-ray radiation. A rotating anode support structure supports the liquid metal anode material in a fixed position with respect to the support structure while rotating at the constant angular velocity. In another aspect, a translational actuator is coupled to the rotating assembly to translate the liquid metal anode in a direction parallel to the axis of rotation. In another aspect, an output window is coupled to the rotating anode support structure. Emitted x-rays are transmitted through the output window toward the specimen under measurement. In another further aspect, a containment window maintains the shape of the liquid metal anode material independent of rotational angular velocity.

Liquid metal rotating anode X-ray source for semiconductor metrology

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San Jose, CA, United States of America

Sergey Zalubovsky