Amit Khanna

Imec iSiPP25G silicon photonics: a robust CMOS-based photonics technology platform

Silicon photonics has become in the past years an important technology adopted by a growing number of industrial players to develop their next generation optical transceivers. However most of the technology platforms established in CMOS fabrication lines are kept captive or open to only a restricted number of customers. In order to make silicon photonics accessible to a large number of players several initiatives exist around the world to develop open platforms. In this paper we will present imec’s silicon photonics active platform accessible through multi-project wafer runs.

Impact of ALD grown passivation layers on silicon nitride based integrated optic devices for very-near-infrared wavelengths

A CMOS compatible post-processing method to reduce optical losses in silicon nitride (Si(3)N(4)) integrated optical waveguides is demonstrated. Using thin layer atomic layer deposition (ALD) of aluminum oxide (Al(2)O(3)) we demonstrate that surface roughness can be reduced. A 40 nm thick Al(2)O(3) layer is deposited by ALD over Si(3)N(4) based strip waveguides and its influence on the surface roughness and the waveguide loss is studied. As a result, an improvement in the waveguide loss, from very high loss (60 dB/cm) to low-loss regime (~5 dB/cm) is reported for a 220 nm x 500 nm Si(3)N(4) wire at 900 nm wavelength. This opens prospects to implement very low loss waveguides.

ePIXfab: the silicon photonics platform

ePIXfab-The European Silicon Photonics Support Center continues to provide state-of-the-art silicon photonics solutions to academia and industry for prototyping and research. ePIXfab is a consortium of EU research centers providing diverse expertise in the silicon photonics food chain, from training users in designing silicon photonics chips to fiber pigtailed chips. While ePIXfab provides world-wide users access to advanced silicon photonics it also focuses its attention to expanding the silicon photonics infrastructure through a network of design houses, access partners and industrial collaborations.

ESSenTIAL: EPIXfab services specifically targeting (SME) industrial takeup of advanced silicon photonics

ePIXfab brings silicon photonics within reach of European small and medium sized enterprises, thereby building on its track record and its integration into Europractice. To this end, ePIXfab offers affordable access to standardized active and passive silicon photonic IC and packaging technology, a path from design to manufacturing and hands-on training. Based on a consortium of major research institutes with silicon photonics expertise, ePIXfab reaches out to European industry and supports them to evaluate silicon photonics in the context of concrete applications and markets. In order to ensure low-cost, quick access and scalability to manufacturing, the maturity of silicon photonic IC technology is enhanced by setting up a library of generic devices, a level of process and device benchmarking and a well maintained design flow. For the first time, devices in a standard package are offered to facilitate measurements. Training programs on the IC and packaging services are also offered, including hands-on training in making designs. Maturity, standardization and sustainability are driven by a steadily growing worldwide user base.

CMOS Cost–Volume Paradigm and Silicon Photonics Production

A clear fabless path to silicon photonics R&D and low volume production is taking shape. Current low volume requirements in silicon photonics pose a price challenge for products. Further, technical challenges for low volume production also need to be addressed. In this chapter we discuss the rapidly evolving macro-landscape in datacom traffic and its impact on silicon photonics, other applications domains and their volume requirements, and stages in low volume production with their associated challenges.

Foundry technology and services for Si photonics

We discuss the progress in development and offering of silicon photonic integration platforms based on 200mm and 300mm wafer technologies. Devices have capability for developing high-speed datacommunication, but are also used for life science applications.

Design Flow Automation for Silicon Photonics: Challenges, Collaboration, and Standardization

Silicon photonics is nothing new. It has been around for decades, but in recent years, it has gained traction as electronic design challenges increase drastically with their atomic-level limitations. Silicon photonics has made significant advancements during this period, but there are many obstacles without an acceptable level of comfort as seen by the lack of semiconductor community involvement. Apart from a series of technological barriers, such as extreme fabrication sensitivity, inefficient light generation on-chip, etc., there are also certain design challenges. In this chapter, we will discuss the challenges and the opportunities in photonic integrated circuit design software tools, examine existing design flows for photonics design and how these fit different design styles, and review the activities in collaboration and standardization efforts to improve design flows.

Non-birefringent cross-slot waveguide

Silicon photonics is a rapidly advancing technology [1]. Silicon based slot-waveguides for high optical mode confinement of quasi-TE (vertical slot) and quasi-TM (horizontal slot) mode have been demonstrated independently [2,3]. These structures are highly birefringent, which limits their usability in photonic devices. We propose a non-birefringent structure based on slot waveguides. To present the idea, a symmetric cross-slot waveguide with horizontal and vertical slots with widths, wsh=wsv=60 nm, in a silicon dioxide environment (nSiO2=1.46) is shown in Fig. 1a. The material of the rail is amorphous silicon (na-Si=3.58) with height, wh=300 nm, and width, wr=120 nm. Also shown is the intensity distribution of the quasi-TE mode in the structure, simulated with the Film Mode Matching (FMM) method [4]. As expected, the quasi-TM mode has the same effective index as the TE mode and its mode field is confined into the horizontal slot.