MEMS Technology: The Mechanical Face of Silicon Revolution

1. Jordan University of Science and TechnologyMicroelecromechanical SystemsDr. Mohammad Kilani

2. Announcement No class on Sunday, 12th of February

3. The Mechanical Face of the Silicon Revolution Mechanical Analog Devices commercializes MEMS airbag accelerometers First silicon pressure sensor First silicon oscillating resonators IBM patents silicon micro-nozzles for inkjet printing Texas Instruments demonstrate Digital Projection Display using digital mirrors Math Logic 1940 1950 1960 1970 1980 1990 2000 1.2 million transistors on a chip 50 MHZ processors 4 MB DRAM 5 million transistor on a chip 2.5 GHZ processors 512 MB DRAM First Integrated Circuits Planar technology invented Commercial Integrated Circuits 64 Bit DRAM Micro-processor invented 64 Kbit DRAM Bell lab develops the semiconductor transistor

4. Characteristics of MEMS Devices • Mechanical functions • Micron-size features • Silicon based • Fabricated using IC fabrication technologies • Integrated with microelectronics • Weight, cost, size, accuracy and reliability

5. Example Commercial MEMS Applications Inertia Measurement Devices Accelerometers: over 100 million sold since 1993 Vibration sensors Rate sensors (Gyroscopes)

6. Example Commercial MEMS Applications Pressure Sensors Pressure sensors for industrial medical and other applications

7. Example Commercial MEMS Applications Microfluidic Devices: Inkjet nozzle Microvalves Lab on a chip Chemical sensors Flow controllers.

8. Example Commercial MEMS Applications Optical MEMS: Displays Optical switches All optical communication Adaptive optics (deformable mirrors) over 11,000 iterations per second was achieved

9. Cartridge Label Sample Entry Well Gasket Fluid Channel Cartridge Cover Sample Entry Well Tape Gasket Biosensor Chips Calibrant Pouch Puncturing Barb Cartridge Base Air Bladder Example Commercial MEMS Applications Biomedical Application Point of care diagnostics Minimally invasive devices Implantable devices

10. Not this … … But things that make it better

11. MEMS Market

12. Photolithography(Photography with depth Mask Substrate

13. Photolithography(Photography with depth Mask Photo resist Substrate

14. Photolithography(Photography with depth UV Light Mask Photo resist Substrate

15. Photolithography(Photography with depth UV Light Mask Photo resist Substrate

16. Photolithography(Photography with depth Resulting pattern Bulk Micromachining Surface Micromachining Substrate

17. Bulk Micromachining The exposed area on the substrate is subjected to further chemical etching Area protected from chemical etching Area exposed to further chemical etching Substrate

18. Bulkmicromachining Anisotropic etching Utilize the crystallographic structure of the silicon lattice

19. Bulkmicromachining Isotropic etching Attack the silicon substrate in all directions with equal rate

20. Bulk micromachining • Large depths • Limited complexity • Piece by Piece fabrication • Manual assembly • Incompatible with IC tools and materials

21. Surface micromachining • Photoresist is used to expose a sacrificial material, which is etch released at the end of the process • Exposed areas of the sacrificial material are used as anchors for an additional level of silicon (polysilicon) Deposit and pattern polysilicon film Etch release sacrificial SiO2 film

22. 20 microns Surface micromachining • Planar • Complex structures with no manual assembly • Compatible with IC tools and materials • Batch fabrication 100 microns 100 microns SUMMiT Layers

23. LPCVD P4, 2.25 microns Dimple 4 gap 0.2 microns PECVD S4, 2.0 microns LPCVD P3, 2.25 microns Dimple 3 gap 0.4 microns PECVD S3, 2.0 microns P2, 1.5 microns S2, 0.3 microns P1, 1.0 microns Dimple 1 gap 0.5 microns LPCVD S1, 2.0 microns P0, 0.3 microns Silicon Nitride, 0.8 microns Thermal SiO2, 0.63 microns Substrate 6-inch wafer, <100> n-type Surface micromachining • Became a standardized technology • An example is Sandia’s SUMMiT technology • Provides five levels of low stress polysilicon • Provides rotational freedom between P1 and P2 levels • Available design tools and components library SUMMiT Layers

24. Sandia Microengine • Uses two two electrostatic comb drives • Uses two input signals for each comb drive and a ground signal • A mechanical linkage converts linear oscillation into continuous rotation at an output gear. • Output speeds up to one-million rpm have been demonstrated 2 mm

25. Microtransmission gear trains

26. Micromirrors for Fiber Optics switching boards and digital displays

27. Micropumps

28. Micropumps

29. Micropumps

30. Systems Engineering Viewpoint Actual Output Desired Output Controller Process Comparison Measurement

31. Microelectronics Systems Engineering Viewpoint Actual Output Desired Output Controller Process Comparison Measurement

32. Micromechatronics Systems Engineering Viewpoint Actual Output Desired Output Controller Process Comparison Measurement

33. Why we should teach MEMS in Jordan • Future Jordanian engineers must participate in developing novel, globally marketed, products. • MEMS is a relatively new field, with a prospect for a number of future innovation. Many products can be improved using MEMS and many other products can be innovated. • Complete MEMS development requires a huge investement in microfabrication infrastructure. However, very few companies do the A-Z in MEMS product development. MEMS development can be performed in design, new fabrication technologies, etc.

35. Micromachines Applications in medical Diagnostics and Treatment

36. Producing a Pin Joint Hub Time etch S1 to produce dimples and anchors Deposit and pattern P1. isotropic etch S1 produce undercut Conformal deposition and patterning of S2 Conformal deposition and patterning of P2 Deposit and pattern S3 and P3 Etch release to produce free standing gear

37. Microsystem Testing Probe Station

38. Applications Micropumps

39. Photolithography(Integrated Circuits Fabrication) UV light Mask Photoresist Photochemical reactions Substrate Resistdevelopment Bulk Micromachining Surface Micromachining

40. 15 mm Microengineering: Designing, Building and Testing Microscopic Feature Devices Eight Legged Microrobot The out-of-plane rotation of the eight legs is obtained by thermal shrinkage of polyimide in V-grooves (PVG). Leg movements is obtained by sending heating pulses via integrated heaters causing the polyimide joints to expand. The size of the silicon legs is 1000x600x30 microns, and the overall chip size of the robot is 15x5x0.5 mm. The walking speed is 6 mm/s and the robot can carry 50 times its own weight World’s smallest helicopter contructed from parts made using LIGA process. With a length of 24 millimeters and a weight of 0.4 grams the helicopter takes off at 40,000 rpm. With a diameter of only 1.9 millimeters the electromagnetic motors can reach an incredible revolution speed of nearly half a million rpm on the one hand, and a considerable torque of 7.5 µNm on the other hand.