Toward Improving the Precision of Nanoscale Force-Displacement Measurements

Published on

Abstract

Nanotechnology has great potential for being used to create better medicines, materials, and sensors. With increasing interest in nanotechnology to improve the quality of our lives, there has been an increasing use of nanoscience tools to measure force and displacement to understand nanoscale phenomena. However, to better exploit the physical attributes of nanoscale phenomena for engineered nanosystems, we must be able to explore the phenomena much more precisely than can be done today. For instance, the atomic force microscope (AFM), which was one of the tools used to begin the nanotechnology revolution, is the force-deflection tool that is most widely used by nanotechnologist today. It is used to measure forces on the order of picoNewtons (similar to the force necessary to rupture DNA) and it is used as a positioner to measure displacements on the order of tenths of nanometers (similar to the size of atoms). However, precise calibration of the AFM is difficult (only about 1% precision), and it is not sensitive enough to measure more subtle nanoscale phenomena, e.g. forces involved in protein folding. Currently, the more subtle nanoscale phenomena are either beyond precise verification, or worse – beyond discovery. In this seminar, I will discus how my group will use microelectromechanical systems to 1) calibrate preexisting force-displacement tools such as the AFM in bending and in torsion; and 2) develop force-displacement tools that are several orders of magnitude more precise and more sensitive than convention.

Bio

Prof. Clark received his Ph.D. in Applied Science from the University of California at Berkeley, and his B.S. in physics from the California State University at Hayward. His research concerns the design, modeling, simulation, and verification of complex engineered systems. The overarching goal is to develop system- level computer-aided engineering and metrology tools to foster and accelerate advancement in tiny technologies for solving societal-scale problems. Application areas include robotics, health, safety, ecology, transportation, communication, etc.

Sponsored by

Cite this work

Researchers should cite this work as follows:

  • Jason Clark (2007), "Toward Improving the Precision of Nanoscale Force-Displacement Measurements," https://nanohub.org/resources/2452.

    BibTex | EndNote

Time

Location

EE Building, Room 317

Tags

Toward Improving the Precision of Nanoscale Force-Displacement Measurements
  • Toward Improving the Precision of Nanoscale Force-Displacement Measurements 1. Toward Improving the Precision… 0
    00:00/00:00
  • Overview of the presentation 2. Overview of the presentation 39.039039039039039
    00:00/00:00
  • Nanotechnology has great potential 3. Nanotechnology has great poten… 57.357357357357358
    00:00/00:00
  • Technological bottleneck. Large uncertainties make it difficult to: 4. Technological bottleneck. Larg… 87.187187187187192
    00:00/00:00
  • Engineering of micro/nanoscale systems 5. Engineering of micro/nanoscale… 169.73640306973641
    00:00/00:00
  • Measuring forces. Tangible phenomena 6. Measuring forces. Tangible phe… 258.958958958959
    00:00/00:00
  • Atomic Force Microscope (AFM): Concept 7. Atomic Force Microscope (AFM):… 388.25492158825494
    00:00/00:00
  • Components of an AFM. 8. Components of an AFM. 437.07040373707042
    00:00/00:00
  • Common methods to calibrate AFM cantilever 9. Common methods to calibrate AF… 452.78611945278612
    00:00/00:00
  • AFM calibration: The thermal method 10. AFM calibration: The thermal m… 468.83550216883555
    00:00/00:00
  • Overview of the presentation 11. Overview of the presentation 553.65365365365369
    00:00/00:00
  • Predicted performance vs. True performance 12. Predicted performance vs. True… 559.5595595595596
    00:00/00:00
  • Dw affects width, gap, length; mass, damping, stiffness; resistance, capacitance; etc. 13. Dw affects width, gap, length;… 603.06973640306978
    00:00/00:00
  • Resonator stiffness kx 14. Resonator stiffness kx 625.658992325659
    00:00/00:00
  • Stiffness is a function of several unknowns 15. Stiffness is a function of sev… 643.00967634300969
    00:00/00:00
  • Relative error in stiffness due to Dw 16. Relative error in stiffness du… 673.03970637303973
    00:00/00:00
  • Relative error in mass due to Dw 17. Relative error in mass due to … 699.36603269936609
    00:00/00:00
  • Relative error in resonance due to Dw 18. Relative error in resonance du… 713.04637971304646
    00:00/00:00
  • Measurements of Young's modulus E 19. Measurements of Young's modulu… 720.72072072072069
    00:00/00:00
  • Relative error in stiffness due to both Dw & DE 20. Relative error in stiffness du… 740.80747414080747
    00:00/00:00
  • Overview of the presentation 21. Overview of the presentation 784.15081748415082
    00:00/00:00
  • EMM: Geometric, dynamic, and material properties as functions of electrical measurands f(DC, DV, and or w) 22. EMM: Geometric, dynamic, and m… 798.16483149816486
    00:00/00:00
  • Electro Micro Metrology (EMM) vs. convention 23. Electro Micro Metrology (EMM) … 829.295962629296
    00:00/00:00
  • A simple EMM structure (not unique) 24. A simple EMM structure (not un… 894.16082749416091
    00:00/00:00
  • Layout versus fabrication 25. Layout versus fabrication 915.14848181514856
    00:00/00:00
  • Close-up of a fabricated comb finger & gap 26. Close-up of a fabricated comb … 943.57691024357689
    00:00/00:00
  • Radius of compliance. The anchor is NOT rigid 27. Radius of compliance. The anch… 967.76776776776785
    00:00/00:00
  • Reducing the effects of filet & anchor compliance 28. Reducing the effects of filet … 991.35802469135808
    00:00/00:00
  • Width by SEM, severed cross section 29. Width by SEM, severed cross se… 1005.538872205539
    00:00/00:00
  • Fabrication vs. effective property extraction 30. Fabrication vs. effective prop… 1036.036036036036
    00:00/00:00
  • Identical comb voltages identical forces 31. Identical comb voltages identi… 1083.1831831831833
    00:00/00:00
  • Static equilibrium by Hooke's law (small deflection) 32. Static equilibrium by Hooke's … 1129.7630964297632
    00:00/00:00
  • Deflections are not identical 33. Deflections are not identical 1139.83983983984
    00:00/00:00
  • And changes in capacitances are not equal 34. And changes in capacitances ar… 1183.0497163830498
    00:00/00:00
  • Forces due to changes in capacitance 35. Forces due to changes in capac… 1207.5408742075408
    00:00/00:00
  • Comb drives have fringing fields, misalignments, strain gradients, etc. 36. Comb drives have fringing fiel… 1228.2282282282283
    00:00/00:00
  • Partial differential ratios = difference ratios 37. Partial differential ratios = … 1258.2916249582918
    00:00/00:00
  • What we get from mechanics 38. What we get from mechanics 1278.0447113780447
    00:00/00:00
  • What we get from electrostatics 39. What we get from electrostatic… 1311.0777444110779
    00:00/00:00
  • Coupling mechanics with electrostatics 40. Coupling mechanics with electr… 1330.9642976309644
    00:00/00:00
  • The difference between layout and fabrication 41. The difference between layout … 1365.4988321654989
    00:00/00:00
  • Planar geometries become available at once! 42. Planar geometries become avail… 1376.71004337671
    00:00/00:00
  • What about parasitic capacitance Cp? 43. What about parasitic capacitan… 1388.2882882882884
    00:00/00:00
  • What about uncertainty in capacitance dC? 44. What about uncertainty in capa… 1424.5245245245246
    00:00/00:00
  • Sensitivity analysis 45. Sensitivity analysis 1439.7731064397731
    00:00/00:00
  • Expectations for geometric extraction 46. Expectations for geometric ext… 1492.0253586920255
    00:00/00:00
  • Expectations for geometric precision 47. Expectations for geometric pre… 1549.5161828495163
    00:00/00:00
  • Expectations for geometric precision 48. Expectations for geometric pre… 1583.5835835835837
    00:00/00:00
  • Measuring comb drive force 49. Measuring comb drive force 1619.1524858191526
    00:00/00:00
  • Measuring comb drive force 50. Measuring comb drive force 1645.7123790457124
    00:00/00:00
  • Sensitivity analysis: F versus uncertainty in e 51. Sensitivity analysis: F versus… 1666.0994327660994
    00:00/00:00
  • Sensitivity analysis: F versus uncertainty in e 52. Sensitivity analysis: F versus… 1675.5422088755422
    00:00/00:00
  • Expectations for force precision 53. Expectations for force precisi… 1687.5875875875877
    00:00/00:00
  • Force: scaling of phenomena 54. Force: scaling of phenomena 1710.0767434100769
    00:00/00:00
  • Position sensing / manipulation 55. Position sensing / manipulatio… 1726.1594928261595
    00:00/00:00
  • Application 1: Calibration / Bending 56. Application 1: Calibration / B… 1753.6536536536537
    00:00/00:00
  • Application 2: Calibration / Torsion / Tribology 57. Application 2: Calibration / T… 1788.154821488155
    00:00/00:00
  • Application 3: AFM-on-a-chip 58. Application 3: AFM-on-a-chip 1805.8391725058393
    00:00/00:00
  • Summary 59. Summary 1823.8238238238239
    00:00/00:00