Improved Semiconductor Device Reliability from Plasma Dicing

Abstract

There are many emerging applications where die strength is critically important, most notably in harsh automotive environments, but also in other areas such as consumer wearables or remote sensing. Plasma dicing using a dry, chemically-driven etch has been introduced into production applications as a viable alternative to traditional methods of wafer dicing, using mechanical saws or LASER based approaches. Both of these conventional techniques create sufficient damage in the silicon as to fundamentally weaken the die. There are, of course, ways to mitigate against this damage, usually at the expense of throughput, but no solution will eliminate the damage these methods cause. The chips and cracks that exist in every die separated by these means could propagate causing a catastrophic failure, with the growth of the fracture accelerated by the external forces. Further benefits of Plasma dicing include a particle free result that is particularly important where die-to-die, or die-to-wafer bonding takes place. Designers can also access non-orthogonal layouts and form factors, with consistent device appearance minimizing inspection demands. Plasma dicing can contribute significantly to improved device reliability and provide positive outcomes for manufacturing yield and costs. This paper will describe factors that have been investigated to enable successful integration of plasma dicing into existing process routes, such as dicing tape compatibility, optimized laser grooving to prepare dicing streets, and post-dicing surface treatments.