Reaching 45nm requires an accelerated flow of innovation
11/01/2005
If the industry is to reach the 45nm node by decade’s end, it will be due, in large part, to a continuing acceleration of the flow of innovation, mostly from the bottom up. While the industry faces unprecedented technical challenges, it has also seen significant consolidation and domination by a relatively few large companies. Though these “mega-companies” compete well in a market where cost reduction through economy of scale is a primary consideration, historically, they have not been a strong source of innovation. Hidden within the trend to consolidate, however, is a vital flow of innovation from small companies to large.
As feature dimensions decrease, so, too, must process tolerances and measurement precision. In CD-SEM, one field of interest at Soluris, 20nm features are smaller than the dimensions of the interaction volume of the electrons at typical beam energies, and the intensity profile of such a feature is no longer a sufficiently accurate representation of its physical shape. Accurate and repeatable measurements require reduced energy and detailed physics-based modeling of beam-sample interactions.
With more complex devices, structures can no longer be regarded as simple 2D layers. Control of 3D shape has become critical as well. Moreover, features cannot be considered in isolation. Proximity effects due to the presence or absence of nearby features play a significant role in processes ranging from lithography to CMP. Controlling these effects requires in-circuit measurements.
Finally, process complexity has been increased by the introduction of new materials that dictate new metrology requirements. For example, the photoresists used with ArF lithography light sources shrink significantly when illuminated by electrons with energies >100eV. Accurate measurements require unconventional electron optics that maintain resolution at ultralow voltage.
As process technology becomes more complex, so must the techniques used to control it. The next five years are likely to see a proliferation of technologies specialized for particular tasks. For CD process control, this will likely mean the combined use of CD-SEM, optical CD, CD-AFM, and FIB/SEM technologies, which will ultimately be seen as complementary, rather than competitive.
There is also an increasing need for metrology capacity. More complex processes have more ways to fail and exhibit greater variability across the wafer and through the process. To control this, manufacturers are adopting larger sampling plans and face expensive measurement technologies and increasing demand for measurement capacity in a competitive environment that will not tolerate price increases to recover the added expense. The result is increasing pressure on equipment manufacturers to improve efficiency and lower total cost-of-ownership.
Accompanying the growing demand for measurement capacity is a growing appreciation for the direct contribution metrology can make to the bottom line through process control improvements. For instance, gate length determines device speed, and variability in speed leads to cumulative errors in circuit timing, which further degrades overall operational speed. Improvements in process control lead directly to higher speed and higher aggregate product value through higher prices for premium performance.
Over the next five years, the Pacific Rim, particularly China, will play a major role in continuing competitive pressure. The high cost of new fabs will exclude all but the largest companies from entering or remaining in the manufacturing sector. Although in recovery, the industry has a cyclical history that makes another downturn likely before the decade’s end, resulting in further consolidation.
Equipment suppliers have also seen significant consolidation, and the segment is dominated by a few major players, yet there remains a healthy distribution of smaller companies that will continue to fill their historic role as innovators. The high entry barriers characteristic of device manufacturing are absent. It is still possible to get a good idea off the ground in little more than a garage.
However, once the idea gains initial acceptance, the need to scale up production, integrate with existing customer infrastructure, provide support, and reduce price through economies of scale generally requires financial resources and practical expertise unavailable to even a well-funded startup. Increasingly, the optimal path to success will be through collaboration or integration with a larger concern. The vital function of innovation will continue to be served by the smaller companies, however, with new entrants appearing just as fast as their older siblings disappear. This process, the flow of innovation from small to large companies, is a sign of a healthy, vibrant industry and will play a vital role in reaching the 45nm technology node by the end of this decade.
 |
For more information, contact Alain Bojarski, president, Soluris Inc., 45 Winthrop St., Concord, MA 01742; ph 978/318-4009.