PRODUCT SPOTLIGHT: Overlay and Film Metrology Systems for 5D Patterning Control Solution
KLA is driving improved patterning by addressing five elements of patterning control ─ the three geometrical dimensions of device structures, time-to-results and overall equipment efficiency. The Archer 500LCM overlay metrology system offers a wide range of measurement options and supports a range of overlay measurement target designs. The SpectraFilm LD10’s laser-driven plasma light source produces reliable, high-precision film measurements for a broad range of film layers.
PATTERNING CONTROL SOLUTIONS
Scatterometry or imaging overlay: a comparative study
In this study, imaging and scatterometry overlay metrology technologies are compared by means of measurements and simulations. Results outline the issues and sensitivities for both technologies and show that some use cases are better suited for either imaging or scatterometry. However, having both measurement capabilities available in parallel on one metrology system, allows overlay engineers to implement a mix-and-match overlay measurement strategy, providing back up when encountering difficulties with one of the technologies and benefiting from the best of both technologies for every use case.
- High order overlay modeling and APC simulation with Zernike-Legendre polynomials
- Overlay accuracy investigation for advanced memory device
- Stack and topography verification as an enabler for computational metrology target design
- Overlay target selection for 20-nm process on A500 LCM
- Lithography process controllers and photoresist monitoring by signal response metrology (SRM)
- Through pitch monitoring by optical scatterometry
DIRECTED SELF-ASSEMBLY PROCESS CONTROL
DSA graphoepitaxy calibrations for contact hole multiplication
Directed Self-Assembly (DSA) is one of the leading candidates for next-generation patterning in IC manufacturing. The graphoepitaxy DSA approach can be used to form single or multiple uniform contact holes well below the resolution limit of the optical exposure tool in a pre-pattern template. In this study, a 3-D Self-Consistent Field Theory (SCFT) model has been developed to describe the behavior of such DSA systems. The utility of the simulator to describe actual physical behavior is explored, by fine tuning the SCFT model input parameters against experimental data for certain pre-pattern configurations and then evaluating the model predictions for other separate pre-pattern shapes.