Here is the abstract you requested from the DPC_2011 technical program page. This is the original abstract submitted by the author. Any changes to the technical content of the final manuscript published by IMAPS or the presentation that is given during the event is done by the author, not IMAPS.
|Through Package Defect Localization by Lock-In Thermography|
|Keywords: defect-localiztion, thermal-emission, package-analysis|
|Root cause analysis for package defects is currently performed by de-processing the package until such defects can be physically seen. However, many such defects within the package are removed, or are confused with defects created during de-processing itself. 3D X-ray has been used to analyze such physical defects within a packaged device in a non-destructive manner. However, the increasing density and associated shrinkage of components such as multi-layered substrates require significantly higher resolutions, which translates to longer times. High resolution X-ray is impractical when searching for a defect over a wide area due to the time to acquire detailed 3D images (~24 hrs). Thermal emission analysis has been widely used for localizing defects on ICs. Recent advancement in thermal emission camera technology coupled with lock-in thermography has allowed orders of magnitude better sensitivity ( < 1 W) and improvement in localization resolution (x,y to < 3 um). However, the application of lock-in thermography has been primarily limited to defect localization at the die level . A a highly sensitive MWIR camera combined with a real time lock-in technique demonstrates the capability to localize defects within packaged devices, even through its mold compound. The technique accurately predicts the depth (z) of a thermal defect within the device (< + 5%) This paper will demonstrate multiple examples of the successful combination of advanced lock-in thermography analysis and high resolution 3D X-ray for totally non-destructive defect location within a packaged device. This initial accurate thermal localization in x, y and z enables the high resolution 3D X-ray system to focus analysis to a few microns so that the defect can be seen quickly (< 1 hr), enabling detection and analysis of previously undetected defects with highest throughput. 1. O Breitenstein et al, ASM-ISTFA 2006, 29. Rudolf's email: email@example.com|
|Rudolf Schlangen, Application Development Engineer
DCG Systems, Inc.