Intel revealed that IBM's approach for optical interconnections for computer chips is quite interesting and progressive, but claims that it may not be efficient in manufacturing. The chip giant defends its own technology, claiming its design is more efficient in terms of performance and manufacturability:
IBM's CMOS Integrated Silicon Nanophotonics combine electrical and optical devices on a single chip. The new IBM technology can be produced on the front-end of a standard CMOS manufacturing line and requires no new or special tooling. With this approach, silicon transistors can share the same silicon layer with silicon nanophotonics devices. According to IBM, the new technology adds just a few more processing modules to a standard CMOS fabrication flow, to enable a variety of silicon nanophotonics components, such as: modulators, germanium photodetectors and ultra-compact wavelength-division multiplexers to be integrated with high-performance analog and digital CMOS circuitry. As a result, single-chip optical communications transceivers can now be manufactured in a standard CMOS foundry, rather than assembled from multiple parts made with expensive compound semiconductor technology.
By contrast, Intel proposes to make chips using the latest process technology on contemporary manufacturing foundries and then add all the necessary elements needed for optical interconnections.