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edfas.org 39 ELECTRONIC DEV ICE FA I LURE ANALYSIS | VOLUME 23 NO . 2 (b) (a) 3. Deposit sputtered chromium • This layer is used as a charge reducer in the SEM. Applying the right thickness of ink takes some experi- menting; you want the ink to completely fill the structure without producing a film that is several microns thick. Keeping the ink film thin ensures straight-forward sample preparation in the FIB/SEM. After the sample is loaded into the FIB/SEM, the area of interest has to be identified under the contiguous carbon/ Cr film. We have found that the CAD layout of the die or a reference die works best. Using this reference, measure the distance to your region of interest and then apply the same measurements to the die you’ve prepared. This will help to locate your structure through the chromium/ ink combination, which is opaque in top-down SEM examination. The SEM images in Fig. 3 illustrate the improvement this technique can have on your TEM sample preparation. Figure 3a shows the conventional preparation method. One can see the electron beam assisted deposition of carbon did not fill the etched-out cavities in the lithogra- phy film. It also illustrateswell the curtaining effect caused by FIB sample preparation with the void present. In contrast, Fig. 3b shows the cross section of the same structure post Cr/ink application. One can see that the ink filled the vias reliably, that no voids are present, and thus the curtaining effect is reduced to a minimum. Fig. 3 (a) Conventional sample preparation using electron assisted carbon deposition in the FIB. Voids are present and strong curtaining is observed. (b) The same structure filledwith theCr/inkmethod. Flawless via filling is observed, and curtaining is reduced to a minimum. Matching job seekers to employers just got easier with ASM International’s CareerHub. After logging on to the ASM website, job seekers can upload a resume and do searches on hiring companies for free. Advanced searching allows filtering based on various aspects of electronics, e.g., R&D, manufacturing, or materials. Employers and suppliers can easily post jobs and set up pre-screen criteria to gain access to highly qualified, professional job seekers around the globe. For more information, visit careercenter.asminternational.org. VISIT THE CAREER HUB