Use of multiple azimuthal angles to enable advanced scatterometry applications

Sendelbach, Matthew; Vaid, Alok; Herrera, Pedro; Dziura, T. G.; Zhang, Michelle; Srivatsa, Arun R.

doi:10.1117/12.846692

Cited by 15 publications

(4 citation statements)

References 7 publications

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“…Then overlay has been fixed to -4nm and afterwards to +4nm. Simulation has been performed with several values of azimuth angle, since it could be a key parameter to improve sensitivity [11] . Figure 5 sums up the results for a standard ellipsometry configuration.…”

Section: Standard and Mueller Matrix Ellipsometry: Sensitivity To Ovementioning

confidence: 99%

Advanced metrology for the 14 nm node double patterning lithography

Carau

Bouyssou

Dezauzier

et al. 2014

Optical Micro- And Nanometrology V

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In microelectronics the two crucial parameters for the lithography step are the critical dimension, which is the width of the smallest printable pattern, and the misalignment error of the reticle, called overlay. For the 14 nm node, the limit of scanner resolution can be overcome by the double patterning technique, which requires a maximum overlay error between the two reticles of 3 nm [1] . The current approach in the measurements of critical dimension and overlay is to treat them separately, but it has become much more complex in the double patterning context, since they are no longer independent. In this paper, a strategy of a common measurement is developed. The aim of the strategy is to measure simultaneously overlay and critical dimension in the metal level double patterning grating before the second etch process. The scatterometry technique is well known for critical dimension measurement. This study demonstrates that the overlay between the two gratings can also be deduced. Thanks to this original scatterometry-based method, it becomes possible to provide information on the lithography step quality before the second etch process; therefore the lithography can be reworked if it is necessary.

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Section: Standard and Mueller Matrix Ellipsometry: Sensitivity To Ovementioning

confidence: 99%

Advanced metrology for the 14 nm node double patterning lithography

Carau

Bouyssou

Dezauzier

et al. 2014

Optical Micro- And Nanometrology V

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“…Scatterometry requires a periodic grating structure and the measurements are conventionally done in a plane of incidence normal to the grating orientation. A multiple plane of incidence solution, also known as azimuthal scatterometry 4 , can be realized by rotating the sample under a fixed angle of incidence using SE. Azimuthal scatterometry is a manufacturing worthy reality, which utilizes a single non-zero azimuth angle or a combination of azimuth angles, in a parallel analyses scheme, to give at hand improved sensitivity to features that are otherwise difficult to fully characterize.…”

Section: Introductionmentioning

confidence: 99%

Enhanced optical CD metrology by hybridization and azimuthal scatterometry

Zangooie

Li²,

Boinapally³

et al. 2014

Metrology, Inspection, and Process Control for Microlithography XXVIII

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Reducing parameter correlations to enhance scatterometry measurement accuracy, precision and tool matching is a crucial component of every modeling effort. Parameter sensitivity can largely depend on the orientation of the plane of incidence relative to the grating orientation. Conventional scatterometry is done with the plane if incidence normal to the grating orientation, whereas azimuthal scatterometry allows measurements at an arbitrary angle or set of angles. A second technique examined in this paper is hybrid metrology where inputs from source tools such as CD-SEM and CD-AFM are used to determine values of critical parameters. The first examples shows LER sensitivity gains by measuring narrow resist lines in an orientation parallel with the long axis of the grating. Hybridization of LER results in a CD and SWA FMP improvement of about 60%. We also showcase the benefits of azimuthal scatterometry measuring resist lines with CD larger than the wavelengths of the incident light. A CD and SWA FMP reduction of about 60% and 30% is obtained using azimuthal scatterometry at 0, 45 and 90 degrees azimuth angles. Hybridization of the ARC SWA after RIE results in CD and resist SWA FMP improvements by over 60% and 30%, respectively.

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“…One advantage of using the spectroscopic ellipsometry (SE)-OCD methods is the wide range of "knobs" available for measurement optimization, including the angle of incidence (AOI), the analyzer angle (AA), the azimuth angle (AZ), 9 and the wavelength range. Sensitivity and correlation analysis are usually simulated and performed prior to the experimental measurements to predict the optimized method.…”

Section: Introductionmentioning

confidence: 99%