By Ardy Johnson, Vice President of Marketing and Product Management, Rudolph Technologies, Inc.
Advanced packaging is in the early stages of a dynamic growth phase. Demand for equipment and related tools in the 3DIC and wafer-level packaging area is forecasted to grow from approximately $370 million in 2010 to over $2.5 billion by 2016. Advanced packaging requirements are driving the evolution of back end manufacturing to become more similar to the front end where the need to tie the entire process together with effective process control has long been established. Rudolph, with a long history in both the front end and back end, is participating fully in this evolution with a “total solution” approach, as exemplified by our recent entry into the back end photolithography market.
Ideally, a photolithography solution for advanced packaging begins with a reduction stepper that is uniquely capable of meeting current and future requirements of advanced packaging processes: greater depth of focus to handle the thicker resists required by exaggerated wafer topography; flexible automation and specialized handling for warped wafers, reconstituted wafers, and large panels; on-the-fly focusing at every exposure to ensure maximum image quality; and an on-board reticle library and fast-change reticle wheel for increased productivity. But the full power of the total solution derives from integrating the stepper with a suite of inspection and metrology tools and process control software: an inspection tool for CD overlay measurements; APC software for closed loop, run to run control; and a yield management system to provide fab-wide, automated, real-time process control feedback.
Fleet management provides another example of the use of automated data collection and analysis to increase equipment uptime, improve yield, and reduce production costs. It monitors the output and operational parameters of inspection and metrology tools performing similar tasks to detect statistical excursions that indicate tool health and stability. One important benefit of fleet management is the ability to improve tool matching-based actual performance.
As backend processes continue to evolve, incorporating the next generation packaging technologies needed to reduce size and increase functionality is a necessity, and manufacturers will derive increasing value from an integrated, total solution approach.