Lennie Kiyama

Micro-G silicon accelerometer using surface electrodes

We present a new technology platform for silicon inertial sensors. The platform combines three technology features to set new performance and manufacturability standards for MEMS sensors. First, bonding three silicon wafers creates wafer level packaging and a homogenous stack of silicon material improving device temperature stability. Second, through-wafer etching is used to define the mechanical structure creating a proof mass with 1000x larger mass than a typical MEMS sensor. Finally, we use surface electrode technology to create a lateral capacitance-based transducer enabling large capacitance change per acceleration and allowing a large dynamic range without electrode contact. The large mass together with reduced damping of a lateral sensor result in substantially reduced thermal-mechanical noise. We present a two axis, in-plane, MEMS accelerometer having nG/√Hz noise performance, over 130 dB dynamic range, 300 Hz bandwidth, and a chip size comparable to other MEMS accelerometers. The platform is extensible to gyroscopes and single chip IMU.

Telecentric Optics for Free-Space Optical Link

We describe a telecentric optical system for free-space multichannel optical interconnects. The targeted aggregate data rate is 240 Gb/s. We have a unique implementation of telecentric optics and achieved an optical link that is simple, robust and modular. The integrity of the optical link is not significantly degraded with a >plusmn2 mm translational misalignment between the transmitter and receiver arrays. With this optical link, we need only a low bandwidth active servo mechanism to compensate for static tilt and possibly low frequency thermally-driven shift between the transmitter and receiver arrays.

OPTOPUS: Optical Backplane for Data Center Switches

An all optically connected data center switch with a Multi-Bus Optical Backplane is demonstrated. The broadcast bus is based on a multimode zig-zag star coupler capable of 1:6 optical broadcast on 12 multi-mode GI fiber channels.

2D optoelectronic engines with wafer scale self-aligned optical cores

A 24 channels (2×12) surface mount, solder reflowable, optoelectronic engine using MEMS manufacturing techniques, wafer scale packaging, and passive alignment is presented. A fiber optic link operating at 16.5 Gbps/channel was demonstrated.