The New Metrology

As we all know, the challenges facing both capital equipment suppliers and device manufacturers are becoming increasingly difficult to solve at an acceptable rate. These challenges generally fall into two categories: technical and economic.

The technical challenges revolve around the need to continually advance along the International Technology Roadmap for Semiconductors (ITRS) in order for the industry to provide increasing device performance and drive the economies of scale required to maintain profitability in a more competitive global environment. These challenges include the constant introduction of new materials and processes required as performance is increased and node size is decreased. For both the device manufacturer and equipment supplier, the most difficult challenges to overcome, however, may not be technical but economic.

Because of the consistent absence of the next "killer app," as evidenced by the reduced influence of the old Wintel alliance, the industry has reached a new maturity. This has resulted in the dramatic reduction of a predictable and repeatable high-volume demand for higher-performing devices. This lack of a killer-app driver has greatly reduced the ability of device manufacturers to premium price products based on device performance and early availability. This trend has also resulted in a consolidating device manufacturing customer base whose strategy is increasingly focused on manufacturing excellence, in addition to technology excellence.

As a result, device manufacturers are increasingly operationally and financially focused, demonstrated by their aversion to risk during the most recent semiconductor upturn. They are much more cost-conscious, as margins are being squeezed more and more by pricing pressures. For the equipment manufacturer, this means that, in addition to developing products that are able to successfully process newly developed devices, they must also satisfy the new economic realities that the industry is facing. Nowhere is this challenge more evident for equipment suppliers than in metrology.

Metrology, by its very nature to operationally driven companies, is a "necessary evil." This is because the actual measurement of a device during its manufacture is not perceived as a value-added step but rather as a cost adder. However, given the huge challenge and accompanying risk of converting entire processes from aluminum to copper and maintaining control on that process in high-volume production, it may be a very valuable and necessary cost adder. To meet these criteria, this "new metrology" must have certain critical features in addition to acceptable measurement capability.

Robustness — New metrology must be robust. This means that the fundamental technology and design must be simple and extremely reliable. These tools must be capable of running daily on a high-volume fab line with little maintenance or calibration. Long-term stability is extremely critical. These tools should not be easily "broken" by normal operator intervention and use. They must have high-quality tool matching capability, as many of these units will be installed throughout the fab.

Speed — New metrology must have high throughput. Today's process tools have increasingly higher throughputs, and the new metrology must keep pace. The last thing a perceived cost adder needs to be is a bottleneck in the process line. In addition, many of today's advanced fabs are running automated process control (APC) to achieve and maintain higher yields. This will become more commonplace as the industry matures. Successful implementation of APC requires the acquisition and processing of large amounts of data in real time. To generate this amount of data, device manufacturers will need to implement high-throughput metrology solutions that can measure, analyze and forward large amounts of data in real time for use in process adjustments.

Cost-Effective — New metrology must be cost-effective. This involves the entire cost of ownership model that includes not only visible costs like sell price but hidden costs as well. Hidden costs include maintenance, downtime, file generation and management, and training requirements. As mentioned before, fab manufacturers are becoming increasingly focused on operational costs. This means that the overall cost of ownership of new metrology will be more heavily weighted in purchase decisions. It is no longer sufficient to just have technology available to provide acceptable measurements. This must also be accomplished in a cost-effective manner to be deemed practical to implement in the process line. Acquiring large amounts of data, in real time, cost effectively is needed by device manufacturers worldwide to remain competitive in the industry's new economic environment.

Flexible — New metrology must be flexible. Today's device manufacturers are implementing high-mix, flexible manufacturing strategies to meet the new market requirements. New metrology must also meet these requirements. This means that new metrology must be able to handle many applications within the fab using the same platform. Recipe generation and maintenance must be fast, simple and robust, as this is becoming a larger part of equipment overhead.

The semiconductor industry is entering an operationally driven era that represents a new set of challenges both technical and economic. Both the device and capital equipment manufacturers must change the way they approach these challenges to remain competitive. It is no longer sufficient to modify strategy and products from the previous technology-driven era. There needs to be some fundamental changes to the approach. The companies that successfully accomplish this will be the new emerging market leaders.