Inline Metrology CD-SEM Hitachi CS4800

For statistical SEM (Scanning Electron Microscope) studies, a Hitachi CS4800 CD-SEM is available for imaging 6" and 8" wafers with varying thicknesses (275 µm to 825 µm). These can be loaded directly from the pod, allowing large quantities to be characterized efficiently (e.g., 40 wafers/h with 5 measurement points per wafer). Transparent substrates can also be handled and imaged. With a resolution of up to 2 nm, images can be captured at magnifications from 4000 to 300,000 times, based on recipes. The reproducibility is at 1 nm/3 sigma or 1%. Alignment and focusing are fully automated, and image analysis is also automatically performed using image recognition, allowing for rapid statistical characterization across the entire wafer.

Highlights:

  • Statistical SEM investigations and evaluation at wafer-level
    • 6" (wafer thickness 275 µm to 775 µm) and 8" (wafer thickness 725 µm ± 100 µm) silicon and glass wafers
    • Special substrates upon request
  • Resolution up to 2 nm
    • Automated measurement programs and analyses
    • Defect Review Package / KLARF / KRF Interface for targeted analysis of already known defects
    • Microscale with 100 nm pitch
Wafer map on the CD-SEM. In the yellow-labeled array with 7 x 7 chips, fully automated measurements of the structure line width were performed. Due to a dose variation over different columns as well as a focus variation over different rows, the line widths vary depending on the position on the wafer.
© Fraunhofer ENAS
Wafer map on the CD-SEM. In the yellow-labeled array with 7 x 7 chips, fully automated measurements of the structure line width were performed. Due to a dose variation over different columns as well as a focus variation over different rows, the line widths vary depending on the position on the wafer.
CD-SEM image of several line structures with automated measurement of the line widths. The value at the top of the image represents the mean value over the line widths measured on four lines in this example.
© Fraunhofer ENAS
CD-SEM image of several line structures with automated measurement of the line widths. The value at the top of the image represents the mean value over the line widths measured on four lines in this example.
Aus den Messdaten erstellte Wafermap, aus der die Linienbreiten in Abhängigkeit von der Dosis und des Fokus abgelesen werden können.
© Fraunhofer ENAS
Wafer map created from the measurement data, from which the line widths can be read as a function of dose and focus.