Convergence of Electronics and Photonics, and MPW Service

Friends, as promised, here's a conclusion of my discussion with Dr. Patrick Guo-Qiang Lo, from the Institute of Microelectronics (IME), Singapore, on the convergence of electronics and photonics, and the MPW service, as well as some research insights on plasmonic and photonic crystal devices.

Elaborating a bit more on the convergence of electronics and photonics, and how it will change the technology landscape, he said that, traditionally, an optical transceiver is fabricated by assembling discrete photonic and electronic components in order to achieve integrated functionality.

“Such an approach is not cost-effective and has limited scalability in terms of performance, component size and functionality. The fully monolithic silicon photonic transceiver chip, which involves the convergence of electronics and photonics on a single silicon chip, will be an enabling building block for future low-cost small form-factor photonic transceivers,” Dr. Guo-Qiang Lo added.

Benefits of MPW service

In anticipation of the convergence of electronics and photonics on a single silicon chip, IME has been actively developing and enhancing its silicon photonics technology platform, which I've touched upon in an earlier post. IME has also launched a multi-project-wafer (MPW) service, which offers high-end fabrication services at a cost affordable to research groups and companies.

Is this service available and who will be its users?

As per the IME spokesperson, since 2008, IME has launched prototyping services in an effort to boost the silicon photonics industry.

Dr. Guo-Qiang Lo noted highlighted that these are divided into two categories -- MPW prototyping and customized prototyping -- both of which offer high-end fabrication services at a cost affordable to research groups and companies.

He added, “MPW prototyping works on the principle of combining designs from various users on shared masks, sharing a large fraction of the process cost among the users. On the other hand, many of IME’s existing partners welcome the flexibility that customized prototyping offers. To shorten the development life-cycle, IME also provides a host of both active and passive baseline photonic devices in its design libraries.”

Fabrication is performed using standard CMOS processes in its 200 mm R&D foundry, which facilitates quick technology transfers to commercial foundries for mass production. The service has proven to be a boost for its targeted users -- fabless companies and research groups.
,br>Those interested to know more, please refer to the IME Web site for more information.

Research in plasmonic and photonic crystal devices

The IME has also been doing some research in plasmonic and photonic crystal devices. How will these benefit users?

Dr. Guo-Qiang Lo advised that the future of silicon photonics is likely to become even more exciting with the development of cutting-edge nanophotonic technologies such as plasmonics and photonic crystals.

“The sizes of silicon photonic waveguides or devices are constrained by the diffraction limit, which is related to the wavelength of light propagating inside the material (i.e., silicon). Researchers have found a way of exceeding this constraint by using plasmonics.

“They discovered that surface plasmons can be generated at a metal-dielectric interface with the same frequency as the impinging electromagnetic waves, but with a much shorter wavelength. By exploiting this effect, it becomes possible to guide optical signals in nanoscale structures, resulting in the miniaturization of the photonic circuits,” he added.

Recently, the IME demonstrated the use of plasmonics to enhance the photo-response of Ge photodetectors. The technology is expected to yield smaller and faster photodetectors.

A photonic crystal is the optical analogue of the semiconductor crystal. Photonic crystals comprise periodic patterns of nanoscale dielectric or metal and dielectric structures. The propagation behavior of electromagnetic waves through a photonic crystal depends on its wavelength.

A photonic crystal can be designed such that certain wavelengths are disallowed or allowed. Control and manipulation of light can also be engineered. Interesting applications of photonic crystals include lossless 90° waveguide bends, compact modulators and even nanocavity lasers.

Dr. Guo-Qiang Lo noted that the IME researchers have also shown the enhanced photoluminescence of light emitting devices with the use of photonic crystals. It is believed that nanophotonic technologies can potentially change the landscape for silicon photonics, allowing for greater miniaturization and taking the performance to new heights.

To be concluded . . .

Pradeep