MTL News Archives for 2016

MTL 2016 Spring Term Doctoral Dissertation Seminar (DDS)
by Dr. Bichoy Bahr

June 6, 2016

Congratulations to Dr. Bichoy Bahr who received the honor of delivering the 2016 MTL Doctoral Dissertation Seminar (DDS) on May 18, 2016.

Dr. Bichoy Bahr (left) and Prof. Jesús del Alamo.
Photo, Valerie DiNardo/MTL.
Dr. Bichoy Bahr recently graduated with a Ph.D. from Professor Dana Weinstein's and Professor Luca Daniel's groups at MTL and earned the honor of presenting his work, in depth, entitled "Monolithically Integrated MEMS Resonators and Oscillators in Standard IC Technology."

Dr. Bahr introduced the benefits of high-Q, monolithically integrated, MEMS resonators and the challenges pertaining to such an integration in standard IC technologies. Focusing next on CMOS technologies, he demonstrated the first implementation of Phononic Crystals (PnCs) in the back-end-of-line (BEOL) layers of the IBM 32nm SOI technology. He showed a numerical framework based on model order reduction and memoization for 40x speed-up of optimization that uses finite element method (FEM) simulation.

Bichoy demonstrated prototypes for unreleased resonant body transistors (RBTs) in IBM 32nm SOI achieving Q~13,500 at 3.15GHz for a record-breaking foxQ ~ 4.3x10^13. He moved into an abstract operator-theoretic analysis of phononic waveguides, explaining their explicit and formal equivalence to photonic waveguides and time-dependent Schrodinger equation; allowing formal analysis for the scattering in grated waveguides through the coupled-mode theory.

Dr. Bahr noted the first monolithic MEMS-based oscillators in GaN MMIC technology based on monolithic Lamb-mode resonators developed by L.C. Popa, and using the MIT Virtual Source (MVS) model, he was able to design and prototype low-power, low-phase noise 1GHz oscillators with world-class performance.

His work paves the way toward ultra-compact, low power monolithic frequency sources, clocks, and complete RF front-ends. The MEMS-MMIC technology development, MEMS resonators, transistor models, circuit design, and fabrication were all performed at Microsystems Technology Laboratories.

During his seminar, Bichoy thanked Professor Dana Weinstein and Professor Luca Daniel for their supervision, his thesis committee member Professor Dimitri Antoniadis for his guidance, and the MTL technical staff and his colleagues inside and outside MIT for their collaboration.

A video of the seminar can be found here.

Congratulations Bichoy!

--Microsystems Technology Laboratories