Cassette-based in-situ TEM sample inspection in the dual- beam FIB

A novel method is presented, combining site-specific TEM sample preparation and in-situ STEM analysis in a dual-beam microscope (FIB/SEM) fitted with a chamber mounted nano-manipulator. TEM samples are prepared using a modified in-situ, lift-out method, whereby the samples are thinned and oriented for immediate in-situ STEM analysis using the tilt, translation, and rotation capabilities of a FIB/SEM sample stage, a nano-manipulator, and a novel cassette. This cassette can provide a second tilt axis, orthogonal to the stage tilt axis, so that the STEM image contrast can be optimized to reveal the structural features of the sample (true STEM imaging in the FIB/SEM). The angles necessary for stage rotation and probe shaft rotation are calculated based on the position of the nano-manipulator relative to the stage and door and the stage tilt angle. A FIB/SEM instrument, equipped with a high resolution scanning electron column, can provide sufficiently high image resolution to enable many failure analysis and process control applications to be successfully carried out without requiring the use of a separate dedicated TEM/STEM instrument. The benefits of this novel approach are increased throughput and reduced cost per sample. Comparative analysis of different sample preparation methods is provided, and the STEM images obtained are shown.