Silicon photonics integrated design

Abstract

Silicon photonics is a fast-growing technology, but the design capability for large-scale photonic-electronic circuits is lacking. Challenges include signal handling, variability and photonic-electronic co-integration. We will discuss these and the tools we are developing.OCIS codes: (130.0130) Integrated optics, (220.0220) Optical design and fabrication IntroductionSilicon photonics is a field of photonics with a rapidly growing industrial interest, with potential applications in communication and sensors. The key strengths of the technology are twofold: silicon is compatible with the manufacturing technology for CMOS, leveraging a huge technology knowledge base [1]. The second strength of silicon photonics is its high refractive index contrast. Silicon and silicon dioxide have an index contrast of more than 2-to-1, which allows submicron waveguides and bends of a few micrometer: Silicon photonic circuits can be made orders-of-magnitude smaller than their low-contrast counterparts. Not just smaller, but more complex: thousands to millions of components can be integrated on a chip. Most optical functions have already been demonstrated in silicon with industrial processes, and the potential to integrate electronics makes it even more attractive.This powerful technology introduces some considerable design challenges. First of all, the high index contrast makes the structures very sensitive to geometrical variations. In the case of wavelength filters, 1nm-scale variations could render a device useless. Designing circuits with tolerances to compensate for variability in the fabrication will be essential to silicon photonics design. Also, complexity itself poses challenges. Simulating circuits with thousands of components is beyond most of today's tools. Most tools are focused on physical component design, and are mostly disconnected from circuit simulators. Also, the photonics will often need cosimulation with electronics. As the physics are very different, this cosimulation requires new tools that can handle the different concepts together.In this paper and presentation, we will discuss these challenges. The solutions are far from complete, and there is not a single tool which will solve all problems. Our own methods use a scripting framework called IPKISS [2] which revolves around a single component definition and brings together tools (even from different vendors) to enable a design flow including physical simulation, circuit synthesis, mask layout and even testing procedures.

Integrated design for integrated photonics: from the physical to the circuit level and back

“…Silicon photonic circuits will, for most applications, require complex control circuitry, and at that point electronic-photonic codesign becomes a necessity, whether the photonic and electronic circuits are collocated on the same die or on separate chips. Electronic design frameworks rely very strongly on parametric building blocks (PCells), a concept which has also been introduced in photonic design environments 13,15 We present IPKISS, 16, 17 a parametric design framework for photonic integrated circuits. 16 It is a componentcentric framework which allows the designer to perform several design and simulation activities from within the same component library, and generate different output based on the same component definition.…”

Design challenges in large-scale silicon photonics

“…An integrated flow where transitions between between design steps is largely automated is therefore desirable. This is an area where EDA has paved the way, and where some early photonics solutions are appearing [1], [2], [3].…”

Dispositivos emisores de luz para transmisión óptica de alta velocidad

“…Sin embargo, las pérdidas de propagación se incrementan principalmente por la rugosidad de las paredes de la guía que dependen en gran parte del proceso de fabricación. Las dimensiones alcanzadas mediante esta tecnología, del orden de nanómetros, son de gran interés para la implementación de circuitos integrados fotónicos, lo que permite reducir aún más el tamaño de los dispositivos de comunicaciones, incrementar sus prestaciones y hacerlos energéticamente eficientes, al utilizar la luz y todas las ventajas que conlleva la tecnología óptica [11].…”