Nanometrics Inc.

Timothy Andrew Johnson

Michael John Darwin

Kevin Eduard Heidrich

Jonathan Peak

Ke Xiao

John Allgair

Brennan Peterson

An interferometric metrology device characterizes a surface topography of a sample at different length scales by combining the interferometric data into blocks of different length scales or by filtering the interferometric data at different length scales and then determining statistical moments or surface properties of the surface topography at the different length scales. The interferometric metrology device determines a best focus position for a processing tool based on different length scales and/or based on weighting functions that are based on the structure-dependent focus budget and a variable local topography. Additionally, the topography data may be used by itself or combined with design data, design simulation depth-of-focus data and lithography scanner focus data to define regions of interest for additional characterization with a different metrology device.

Interferometric characterization of surface topography

An optical metrology device determines physical characteristics of at least one via in a sample, such as a through-silicon vias (TSV), using signal strength data for modeling of the bottom critical dimension (BCD) and/or for refinement of the data used to determine a physical characteristic of the via, such as BCD and/or depth. The metrology device obtains interferometric data and generates height and signal strength data, from which statistical properties may be obtained. The height and signal strength data for the via is refined by removing noise using the statistical property, and the BCD for the via may be determined using the refined height and signal strength data. In one implementation, a signal strength via map for a via is generated using signal strength data and is fit to a model to determine the BCD for the via.

Via characterization for BCD and depth metrology

An optical metrology device determines the local stress in a film on a substrate. The metrology device maps the thickness of the substrate prior to processing. After processing, the metrology device determines the surface curvature of the substrate caused by the processing and maps the thickness of a film on the top surface after of the substrate after processing. The surface curvature of the substrate may be determined as basis functions. The local stress in the film is then determined using the mapped thickness of the substrate, the determined surface curvature, and the mapped thickness of the film. The local stress may be determined using Stoney's equation that is corrected for non-uniform substrate curvature, non-uniform film thickness, and non-uniform substrate thickness.

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Tigard, OR, United States of America

Timothy Andrew Johnson