New Standards for Cleanroom Grades and Environmental Requirements in Advanced Packaging

Advanced packaging has changed the rules of semiconductor manufacturing, and cleanroom standards are changing with it. What used to be a largely front-end concern is now a packaging concern too, because heterogeneous integration depends on much more than just transistor quality. It depends on the cleanliness of bonding surfaces, the stability of thin wafers, the behavior of mold compounds, the integrity of fine-pitch interconnects, and the control of particles, humidity, and temperature throughout assembly. In short, the environment has become part of the design.