The first of the new capabilities that IAL will be offering as an extension of our currently available electron microscopy services is large area image acquisition, often referred to as “mosaics”. Previously, a customer interested in imaging a large area (for example, a large functional block on a deprocessed die) would either be forced to sacrifice resolution in order to fit the entire area in a single image, or sift through countless high magnification images, manually aligning the individual frames with one another in order to create a composite image of the entire area of interest. Obviously, neither of these options was particularly attractive; a low resolution image often is insufficient for the demanding analyses performed by some clients, while the second option entails hours upon hours locked in a dark room, illuminated only by the faint glow of the SEM monitor, acquiring all the necessary images, manually moving the sample from frame to frame, desperately hoping that an important feature of the device was not accidentally skipped. Fortunately, the FEI tool offers an alternative to this arduous process, in the form of its “MAPS” tool. With MAPS, an engineer can define an area of interest on a device, perform an initial configuration of imaging conditions (focus, stigmation, resolution requirements, and so on), and kick the tool into gear. Using the automated, high-precision stage, the tool will then acquire enough images to cover the entire area of interest without any further intervention from the operator, creating a single massive composite image of incredible resolution.
In addition to large area imaging, IAL will also be able to expand our range of cross-section services, augmenting our mechanical cross-sections of integrated circuits with focused ion beam sectioning capability. While mechanical cross-sections will certainly not be replaced, as their value in performing construction analysis is undeniable given their ability to reveal a much larger relative area of the die than a FIB section, the FIB offers a higher degree of speed and accuracy. Since the FIB is integrated with the electron microscope, incredible precision is possible; for example, given the proper documentation, a single transistor may be targeted for cross-sectioning with a high degree of certainty. In addition, a high resolution video may be taken concurrently with the sectioning process to provide a tomographic view of the transistor. The FIB cross-section can also be performed much more quickly than a mechanical section, especially when a specific site has been targeted; since the FIB does not need to remove all the bulk material that a mechanical cross-section would, the amount of sample prep time can decrease by as much as a factor of four depending on the complexity of the analysis.
IAL will also be expanding its range of electron microscopy services with the addition of scanning transmission electron microscopy (STEM), with sample preparation and imaging facilitated by the Versa dual beam. The sub-nanometer resolution offered by the STEM is invaluable for materials characterization and construction analysis, providing a level of detail previously unattainable by the tools at IAL. We will also be augmenting this capability with the addition of an energy dispersive spectroscopy (EDS) system for the Versa tool, facilitating high resolution elemental mapping to provide an incredible level of detail for analysis. We anticipate the delivery of the EDS in March/April of 2013 and hope to be able to integrate it into our analysis flow without delay.
The addition of the Versa 3D dual beam tool to IAL’s arsenal, along with the corresponding expansion of our electron microscopy services, represents incredible progress for our company. For additional information about the services listed in this article, or any other services offered by IAL, feel free to fill out our contact form or give us a call and we will be glad to assist!
Derek Snider is a failure analysis engineer at Insight Analytical Labs, where he has worked since 2004. He received his Bachelor’s of Science in Electrical Engineering from the University of Colorado at Colorado Springs.