3 D MEMS Accelerometers for Building Applications Mikal

3 D MEMS Accelerometers for Building Applications Mikaël Colin – MEMSc. AP S. A. 1 st MEMSCON Event – Bucharest October 7 th, 2010 1 st MEMSCON Event 07/10/10, Bucharest Company

Acceleration RF ID tag 3 D MEMS accelerometer Accelerometer end-user specifications Parameter Value Unit Acceleration 0. 01 -2 g Frequency 0. 1 -10 Hz Duration 15 s Size constraint - mm 3 Operating temperature -20 to +50 °C Operating Humidity 0 to 100 %RH Vibrations (15 g) 1000 Hz Shocks 2000 g Battery lifetime 2 years MEMS = Micro Electro. Mechanical System 1 st MEMSCON Event - 07 October 10, Bucharest MEMSc. AP, France

Accelerometers transduction mechanisms l Vibration Beam Accelerometer (VBA) l l l Resonance frequency is dependent on the applied force Driven oscillator at resonance frequency (closed loop) High end applications l Spring Mass System l l 1 st MEMSCON Event 07/10/10, Bucharest Acceleration force causes a proof mass displacement Displacement measurement system Direct or indirect measurement Indirect measurement methods: l Piezoelectric effect l Piezoresistive effect l Capacitive sensing Company

Transduction principles l Piezoelectric effect l Capacitive sensing l Piezoresistive effect 1 st MEMSCON Event - 07 October 10, Bucharest MEMSc. AP, France

MEMS Technologies l Bulk micromachining l Surface micromachining l Hybrid integration 1 st MEMSCON Event - 07 October 10, Bucharest MEMSc. AP, France

Concept of 3 D accelerometer l Mounting of 3 1 D accelerometers l 3 -axis sensitive mechanical structure l 3 independent structures on the same die 1 st MEMSCON Event - 07 October 10, Bucharest MEMSc. AP, France

Selected concept l 3 independent capacitive micromachined sensors on a single die ~ 4 mm Out of the wafer plane sensitivity ~ 11 mm 1 st MEMSCON Event - 07 October 10, Bucharest In plane sensitivity MEMSc. AP, France

Fabrication l Wafer level packaging concept 1 st MEMSCON Event - 07 October 10, Bucharest MEMSc. AP, France

ASIC+MEMS Assembly l Hybrid integration in a ceramic carrier ASIC Read-out MEMS 1 st MEMSCON Event - 07 October 10, Bucharest MEMSc. AP, France

Thank you for your attention 1 st MEMSCON Event - 07 October 10, Bucharest MEMSc. AP, France