Resist-on-silicon sub-50 nm targets have been investigated using a 193 nm angle-resolved scatter field microscope(ARSM). The illumination path of this microscope allows customization of the Conjugate Back Focal Plane (CBFP) while separate collection paths permit both high-magnification cation and Fourier-plane imaging. Aspects of the calibration of this microscope are presented. Full- field, Fourier-plane images are collected as individual targets are illuminated using a field-of-view smaller than the target size; the range of incident polar angles corresponds to the Numerical Aperture (NA) of the objective, NA = 0.08 to 0.74. Next, angle-resolved scatter field high-magnification cation imaging of these same targets are acquired in a conical mounting con figuration by scanning the 12 mm diameter CBFP with a 1 mm diameter aperture. The results of these measurements and the prospects for quantitative, simultaneous measurement of multiple targets are discussed.
Proceedings Title: Proceeding of SPIE Metrology, Inspection,and Process Control for Microlithography XXIV
Conference Dates: February 22-March 25, 2010
Conference Location: San Jose, CA
Pub Type: Conferences
DUV scatterfi eld microscopy, Fourier-plane imaging, simultaneous multi-targets measurements