The evolution of semiconductor electronics from mostly discrete components on a printed circuit board to large-scale integrated circuits has provided a sort of benchmark that often is used when optoelectronic integration is being discussed. Current semiconductor ICs combine tens of millions of components onto a single chip but optical integration, which is still in its early infancy, combines a few hundred components at best. But the continuing example set by the semiconductor industry—that very large-scale integration (VLSI) delivers significant benefits in terms of component manufacturability, reliability, and cost/performance ratio—has served to reinforce the strong optical communications market demand and drive considerable development efforts toward the mass production and high-density integration of optoelectronic components and devices. Hence, planar lightwave circuits, such as arrayed waveguide gratings, were much in evidence during the National Fiber Optic Engineers Conference (NFOEC; Denver, CO) last August. Such techniques also have enabled planar laser arrays (vertical cavity surface emitting lasers or VCSELs) to be produced for various applications including reprographics (see p. 143).
But planar technology is only one approach to integrating optical devices and does not address other key manufacturing issues. Automating alignment of optical fiber to components like lasers and waveguides, for instance, is key to the mass production of some devices and involves the use of high-precision automated positioning equipment (see p. 103). The semiconductor industry model also has highlighted the long-term importance of manufacturing to the ultimate success of commercial ventures. That this message has been received loud and clear in the optical arena is clearly illustrated by the early attention being paid by optoelectronics startups to manufacturing—with some firms even installing manufacturing control software during the engineering phase of product development (see p. 67).