World’s Smallest Silicon Photonic MEMS Switch Ever Reported Optics Express, Vol. 26, No. 26, 33906 (24 Dec 2018) │ DOI: 10.1364/OE.26.033906 Fully fabricated at Junichi Nishizawa Memorial Research Center, Tohoku University, Japan (Japan’s largest and most advanced photonics/MEMS cleanroom)

Extreme Challenge → Fully Achieved on First Wafer

• Single switch cell: only 125 μm × 125 μm – currently the world’s smallest silicon photonic MEMS matrix unit ever published
• Complete 8×8 matrix (64 switches) packed in just 1 mm × 1 mm
• Critical coupling gap precisely controlled to 109 nm using lateral comb-drive actuators
• 250 nm SOI, single-mask process, only two etch steps
• 100 % yield – every one of the 64 switches on every die worked perfectly from the very first wafer
• Port isolation: 16.7 dB │ Insertion loss: < 1 dB │ Switching time: 36.7 μs
• Endurance: > 1 billion cycles, no degradation

This result remains the size record for functional silicon photonic MEMS switches and demonstrates that even the most aggressive nanophotonic MEMS structures can be realized with perfect yield in a single run.