Implementing Planar Waveguide Technology - Technology Information

Computer Technology Review, March, 2001 by Terry Caves

The market for optical networking components is growing at a staggering rate. Some 4,000 miles of new glass fiber are deployed every day. Telecom operators, frantic in their need to increase network capacity, are clamoring to ensure their access to the core building blocks of fiber infrastructure. This situation has industry analysts predicting continued dramatic growth for the sector, with even conservative estimates placing yearly increases in the use of fiber optics at more than 35 percent. By 2004, the worldwide market for optical components is expected to hit $24 billion (See Fig).

But there is an important caveat to this rosy picture. The manufacturing processes that have taken the optical components market this far are not up to the task of bringing it to the next level. Current processes simply aren't scalable or robust enough to meet dramatically increasing demand. Fortunately, there are new processes--or rather new applications of established manufacturing technologies--that can meet the demand, while at the same time reducing costs and time-to-market, improving yields, and giving the industry more flexibility.

Optical components expand the bandwidth capacity of fiber networks by breaking the laser light that carries data through the network into different colors, or wavelengths. Each resulting wavelength is capable of carrying a discrete data channel. Optical components therefore enable fiber networks to transmit vastly more information.

Companies like Corning and JDS Uniphase, which specialize in the design and manufacture of optical components, have enjoyed incredible growth in the recent past, spurred by the needs of system providers to accommodate the delivery of more and more data through their systems. To date, these companies have benefited from circumstances supporting near monopolistic conditions because the barriers to entry into the components business have been so high. The optical component business is characterized by long design cycles, short product cycles, and prohibitive capital requirements. Typical component manufacturing processes demand extensive manpower and vast and specialized manufacturing facilities.

But given the vast size of the emerging market for optical components, even these market leaders aren't ideally positioned. Despite ongoing efforts to ramp-up production capacity, many of the industry's giants are facing six-month order lead-times in order to accommodate the delivery of even basic components. In a market characterized by such a rapid pace of technological advancement and the high costs of addressing these advances, these companies are running full speed just to stay in the same place.

As the market progresses along a curve of exponential growth, it becomes increasingly evident that the large thin-film filter process manufacturers will not dominate the market based on their size alone. At the end of the day, optical component makers not only have to be able to produce products in high volume, but they have to be able to stay very close to technology's leading edge. Ironically, it appears that the same "high barrier" conditions that once made life ideal for the industry's big players are now setting the stage for a dramatic industry shake-up that might leave the 800-pound gorillas behind.

As the demand for more, and increasingly specialized, components intensifies, a number of smaller companies are emerging in order to meet the challenge. Equally at issue for these new players is the ability to ramp-up to a significant production capacity. As always, speed is the determining factor. The key to a breakthrough has relatively little to do with an impressive collection of registered patents, and everything to do with the more decisive ability to deliver needed product on a mass scale.

The crux of the issue is neither between established and emerging powers, nor even between companies and their competing technologies. The real issue is how quickly and easily new technology can be embraced and promoted by automated, large-scale manufacturing.

Thin-Film Processes

The prevailing approach to designing and producing passive optical components is based on a technological process known industry-wide as thin-film filter processing. Essentially, this process applies multiple layers of film to a single piece of glass in order to carry photons between component channels.

A defining characteristic of the manufacturing processes implicit to thin-film filter applications is the amount of manual labor required. As an example, consider a 16 channel DWDM, a standard optical networking component that splits a single signal into 16 signal streams. With the standard thin-film approach, armies of technicians are dedicated to the highly specialized and laborious task of joining two different strands of material together with a special adhesive. Each setting takes approximately 20 minutes to complete. Add to this the fact that each component of this type will require 16 similar connections, and that these will typically require a 50 percent rework rate in order to achieve the desired specifications.