Use of FIB to Identify Opens in Metal - Metal Bonds

Abstract

Although the FIB (Focused Ion Beam) is the cross sectioning tool of choice in failure analysis [1], it is not often used in these applications. A typical FIB cross section is 20 μm wide and 5-8 μm deep but a ball bond is 75-100 μm tall and ~30 μm thick and solder balls are typically at least 400 μm in diameter. Even with the latest high throughput machines, FIB cross sectioning of these open failures is simply not feasible. Although IC package cross sectioning can’t realistically be done in a FIB, it is still an indispensable tool for these types of analyses.