PhD Defense: "2.5D Embedded Wafer Level Processing for Optoelectronic Integration"

Avantika Sodhi

November 30th (Wednesday), 2:00pm
Engineering Science Building (ESB), Room 1001

Tremendous development made in the field of band gap engineering in the 1980s and 1990s enabled design of new semiconductor devices for a wide range of applications. The three main components of these applications are communication, data storage and data processing. While the performance of silicon CMOS technologies for data storage and processing remains unmatched, III-V compound semiconductors appear promising for high frequency, high throughput, efficient communication system design. Currently, several research efforts are directed towards finding a unified platform on which all of the stated components can be realized with competitive performance at low cost and a promise for scaling. The unavailability of such a platform has seen emergence of innovative package design technologies to leverage the untapped potential of existing devices in system level applications.
In this talk I will discuss the challenges faced by the existing 2.5D/3D integration technologies and propose a new heterogeneous die integration method that enables more efficient system level design. To demonstrate the potential of the developed technology, we have studied two systems that address some of the critical challenges faced in designing power efficient components for high throughput optical communication.

In the first system, low power electronics is combined with low power optical switching elements to form a scalable, switching unit with output power equalized by a digitally tunable control loop. This unit arranged in a dilated Benes network could realize a photonic switch that consumes 2.7 pJ/bit/port with a time constant of 3.8 ns at 100Gb operation, demonstrating 4.8X improvement over state-of-the-art electronic switches in a compact footprint (11mmX10mm). As a second application we demonstrate a novel distributed drive control for a Mach­Zehnder Modulator (MZM). Close integration and a segmented drive help overcome the modulation bandwidth limitation due to RF loss experienced along the path of a Traveling Wave Electrode (TWE) in a conventional TWE­MZM. This design can enable realization of a temperature insensitive, high optical bandwidth (~100nm), high modulation bandwidth (>20 GHz) optical modulator with a low drive voltage (<1V).

About Avantika Sodhi:

photo of Avantika Sodhi Avantika received her B. Tech in Instrumentation and Control Engineering from Netaji Subhas Institute of Technology, Delhi, India, in 2009 and M.S. in Electrical Engineering at University of California, Santa Barbara with emphasis on Electronics and Photonics in 2012. She joined the Biomimetic Circuits and Nanosystems Group at the University of California, Santa Barbara in summer of 2011 and is currently a PhD candidate in Electrical Engineering at UCSB under the supervision of Prof. Luke Theogarajan. Her current research interests include Opto-Electronic integration, using 2.5D embedded Wafer Level Processing for the design of ultra-fast low-power optical packet switching.

Hosted by: Professor Luke Theogarajan