Assia Barkai

Development of CMOS-Compatible Integrated Silicon Photonics Devices

This paper surveys technical challenges involved in designing and manufacturing integrated optoelectronic devices in a high-volume complementary metal-oxide-semiconductor (CMOS) microelectronic fabrication facility. The paper begins by introducing the motivations for building these devices in silicon. We discuss the advantages and challenges of both hybrid and monolithic strategies for optoelectronic integration. We then discuss the issues involved in building the devices in a standard CMOS facility, including specific technical examples. These include low-loss waveguides (WGs) for Raman lasers, fast silicon modulators, SiGe heterostructures for infrared photodetection, silicon-oxynitride (SiON) devices on silicon-on-insulator (SOI), silicon optical bench (SiOB) technology, and waveguide tapers. We conclude with a discussion and recommendations for future work in silicon photonics

Silicon-on-insulator eight-channel optical multiplexer based on a cascade of asymmetric Mach-Zehnder interferometers

A monolithically integrated eight-channel optical multiplexer (Mux) with a 400 GHz channel spacing ~1550 nm is presented based on a silicon-on-insulator rib waveguide and an asymmetric Mach-Zehnder interferometer. All channels were optimized independently with integrated heaters. The fully tuned Mux shows an adjacent channel isolation of ~13 dB, an excess loss of ~2.6 dB, and a channel uniformity of ~1.5 dB over a 25 nm wavelength span. In addition, the phase tuning efficiency for different interlevel dielectric layer thicknesses and thermal crosstalk were investigated.

Integrated silicon photonics for optical networks [Invited]

Feature Issue on Nanoscale Integrated Photonics for Optical Networks Fiber optic communication is well established today in long-haul, metro, and some data communication segments. Optical technologies continue to penetrate more into the network owing to the increase in bandwidth demands; however, they still suffer from too expensive solutions. Silicon photonics is a new technology developing integrated photonic devices and circuits based on the unique silicon material that has already revolutionized the face of our planet through the microelectronics industry. This paper reviews silicon photonics technology at Intel, showing how using the same mature, low-cost silicon CMOS technology we develop many of the building blocks required in current and future optical networks. After introducing the silicon photonics motivation for networks, we discuss the various devices--waveguides, modulators, Raman amplifiers and lasers, photodetectors, optical interconnects, and photonic crystals--from the points of view of applications, principle of operation, process development, and performance results.

Efficient Mode Converter for Coupling between Fiber and Micrometer Size Silicon Waveguides

A low-loss polarization independent mode converter for coupling standard single mode fiber to a silicon chip is presented. For a micrometer size silicon waveguide, we demonstrate a coupling loss of 1-1.5 dB/facet.

Silicon photonic integration for high-speed applications

Photonic integration is one of the important ways to realize low cost and small form factor optical transceivers for future high-speed high capacity I/O applications in computing systems. The photonic integration on silicon platform is particularly attractive because of the CMOS photonics and electronics process compatibility. In this paper, we present design and fabrication of a silicon photonic integrated circuit that is capable of transmitting data at hundreds gigabits per second. In such an integrated chip, 8 high-speed silicon optical modulators with a 1:8 wavelength demultiplexer and an 8:1 wavelength multiplexer are fabricated on a single silicon-on-insulator (SOI) substrate. We review the recent results of individual silicon modulator based on electric-field-induced carrier depletion in a SOI waveguide containing a reverse biased pn junction. We characterize the individual multiplexer/demultiplexer as well as the integrated chip. The basic functionality of the photonic integration is demonstrated.

Integrated triplexer on silicon

We demonstrate an integrated triplexer on silicon with a compact size of 1mm by 3.5mm. One 1310nm laser and two photodetectors responsive at 1490nm and 1550nm wavelengths are successfully integrated on a silicon-based demultiplexer through a single bonding step, selective area wafer bonding. The 3dB bandwidth of the laser and photodetector are measured to be 2GHz and 16GHz, respectively.