Abstract

Resonance characteristics of a tuning fork are investigated to enhance the shear-force detection sensitivity for near-field scanning optical microscopy. In particular, we show that the asymmetric frequency response of a tuning fork can be utilized to increase quality factors and suppress the background feedback signal. The pinning down effect on one side of the main peak can readily elevate vertical sensitivity and stability. A simplified model based on a coupled harmonic oscillator is presented to describe the asymmetric resonance behavior of the tuning fork. We also show improved topographic images of a blue-ray disc and optical images of a chromium pattern on the quartz using the asymmetric resonance.

© 2004 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |

  1. D. W. Pohl, W. Denk, and M. Lanz, �??Optical stethoscopy: image recording with resolution λ/20,�?? Appl. Phys. Lett. 44, 651 (1984).
    [CrossRef]
  2. E. Betzig, J. K. Trautman, T. D. Harris, J. S. Weiner, and R. L. Kostelak, �??Breaking the diffraction barrier: optical microscopy on a nanometric scale,�?? Science 251, 1468 (1991).
    [CrossRef] [PubMed]
  3. R. Toledo-Crow, P. Yang, Y. Chen, and M. Vaez-Iravani, �??Near-field differential scanning optical microscope with atomic force regulation,�?? Appl. Phys. Lett. 60, 2957 (1992).
    [CrossRef]
  4. E. Betzig, P. L. Finn, and J. S. Weiner, �??Combined shear force and near-field scanning optical microscopy,�?? Appl. Phys. Lett. 60, 2484 (1992).
    [CrossRef]
  5. K. Karrai and R. D. Grober, �??Piezoelectric tip-sample distance control for near-field optical microscopes,�?? Appl. Phys. Lett. 66, 1842 (1995).
    [CrossRef]
  6. A. G. T. Ruiter, J. A. Veerman, K. O. van der Werf, and N. F. van Hulst, �??Dynamic behavior of tuning fork shear-force feedback,�?? Appl. Phys. Lett. 71, 28 (1997).
    [CrossRef]
  7. T. Okajima and S. Hirotsu, �??Study of shear force between glass microscope and mica surface under controlled humidity,�?? Appl. Phys. Lett. 71, 545 (1997).
    [CrossRef]
  8. W. A. Atia and C. C. Davis, �??A phase-locked shear-force microscope for distance regulation in near-field optical microscopy,�?? Appl. Phys. Lett. 70, 405 (1997).
    [CrossRef]
  9. M. J. Gregor, P. G. Blome, J. Schöfer, and R. G. Ulbrich, �??Probe-surface interaction in near-field optical microscopy: The nonlinear bending force mechanism,�?? Appl. Phys. Lett. 68, 307 (1996).
    [CrossRef]
  10. Y. Martin, C. C. Williams, and H. K. Wickramashinghe, �??Atomic force microscope-force mapping and profiling on a sub 100 °A scale,�?? J. Appl. Phys. 61, 4723 (1987).
    [CrossRef]
  11. R. D. Grober, J. Acimovic, J. Schuck, D. Hessman, P. J. Kindlemann, J. Hespanha, A. S. Morse, K. Karrai, I. Tiemann, and S. Manus, �??Fundamental limits to force detection using quatz tuning froks,�?? Rev. Sci. Instrum. 71, 2776 (2000).
    [CrossRef]
  12. R. S. Decca, H. D. Drew, and K. L. Empson, �??Mecahnical oscillator tip-to-sample separation control for near-field optical microscopy,�?? Rev. Sci. Instrum. 68, 1291 (1997).
    [CrossRef]
  13. J. Salvi, P. Chevassus, A. Mouflard, S. Davy, M. Spajer, and D. Courjon, �??Piezoelectric shear force detection: a geometry avoiding critical tip/tuning fork gluing,�?? Rev. Sci. Instrum. 69, 1744 (1998).
    [CrossRef]
  14. A. V. Zvyagin, J. D. White, M. Kourogi, M. Kozuma, and M. Ohtsu, �??Solution to the bistability problem in shear force distance regulation encountered in scanning force and near-field optical microscopes,�?? Appl. Phys. Lett. 71, 2541 (1997).
    [CrossRef]
  15. D.P. Tsai and Y. Y. Lu, �??Tapping-mode tuning fork force sensing for near-field scanning optical microscopy,�?? Appl. Phys. Lett. 73 2724 (1998)
    [CrossRef]
  16. L. Meirovitch, Fundamentals of Vibrations (McGraw-Hill, New York, 2001).
  17. M. Ro, K. Lee, D. Yoon, I. Hwang, C. Park, Y. Kim, I. Park, and D. Shin, �??Experimental results of 3-piece 0.4mm molded substrate,�?? Jpn. J. Appl. Phys. 40, 1666 (2001).
    [CrossRef]

Appl. Phys. Lett. (10)

R. Toledo-Crow, P. Yang, Y. Chen, and M. Vaez-Iravani, �??Near-field differential scanning optical microscope with atomic force regulation,�?? Appl. Phys. Lett. 60, 2957 (1992).
[CrossRef]

E. Betzig, P. L. Finn, and J. S. Weiner, �??Combined shear force and near-field scanning optical microscopy,�?? Appl. Phys. Lett. 60, 2484 (1992).
[CrossRef]

K. Karrai and R. D. Grober, �??Piezoelectric tip-sample distance control for near-field optical microscopes,�?? Appl. Phys. Lett. 66, 1842 (1995).
[CrossRef]

A. G. T. Ruiter, J. A. Veerman, K. O. van der Werf, and N. F. van Hulst, �??Dynamic behavior of tuning fork shear-force feedback,�?? Appl. Phys. Lett. 71, 28 (1997).
[CrossRef]

T. Okajima and S. Hirotsu, �??Study of shear force between glass microscope and mica surface under controlled humidity,�?? Appl. Phys. Lett. 71, 545 (1997).
[CrossRef]

W. A. Atia and C. C. Davis, �??A phase-locked shear-force microscope for distance regulation in near-field optical microscopy,�?? Appl. Phys. Lett. 70, 405 (1997).
[CrossRef]

M. J. Gregor, P. G. Blome, J. Schöfer, and R. G. Ulbrich, �??Probe-surface interaction in near-field optical microscopy: The nonlinear bending force mechanism,�?? Appl. Phys. Lett. 68, 307 (1996).
[CrossRef]

D. W. Pohl, W. Denk, and M. Lanz, �??Optical stethoscopy: image recording with resolution λ/20,�?? Appl. Phys. Lett. 44, 651 (1984).
[CrossRef]

A. V. Zvyagin, J. D. White, M. Kourogi, M. Kozuma, and M. Ohtsu, �??Solution to the bistability problem in shear force distance regulation encountered in scanning force and near-field optical microscopes,�?? Appl. Phys. Lett. 71, 2541 (1997).
[CrossRef]

D.P. Tsai and Y. Y. Lu, �??Tapping-mode tuning fork force sensing for near-field scanning optical microscopy,�?? Appl. Phys. Lett. 73 2724 (1998)
[CrossRef]

J. Appl. Phys. (1)

Y. Martin, C. C. Williams, and H. K. Wickramashinghe, �??Atomic force microscope-force mapping and profiling on a sub 100 °A scale,�?? J. Appl. Phys. 61, 4723 (1987).
[CrossRef]

Jpn. J. Appl. Phys. (1)

M. Ro, K. Lee, D. Yoon, I. Hwang, C. Park, Y. Kim, I. Park, and D. Shin, �??Experimental results of 3-piece 0.4mm molded substrate,�?? Jpn. J. Appl. Phys. 40, 1666 (2001).
[CrossRef]

Rev. Sci. Instrum. (3)

R. D. Grober, J. Acimovic, J. Schuck, D. Hessman, P. J. Kindlemann, J. Hespanha, A. S. Morse, K. Karrai, I. Tiemann, and S. Manus, �??Fundamental limits to force detection using quatz tuning froks,�?? Rev. Sci. Instrum. 71, 2776 (2000).
[CrossRef]

R. S. Decca, H. D. Drew, and K. L. Empson, �??Mecahnical oscillator tip-to-sample separation control for near-field optical microscopy,�?? Rev. Sci. Instrum. 68, 1291 (1997).
[CrossRef]

J. Salvi, P. Chevassus, A. Mouflard, S. Davy, M. Spajer, and D. Courjon, �??Piezoelectric shear force detection: a geometry avoiding critical tip/tuning fork gluing,�?? Rev. Sci. Instrum. 69, 1744 (1998).
[CrossRef]

Science (1)

E. Betzig, J. K. Trautman, T. D. Harris, J. S. Weiner, and R. L. Kostelak, �??Breaking the diffraction barrier: optical microscopy on a nanometric scale,�?? Science 251, 1468 (1991).
[CrossRef] [PubMed]

Other (1)

L. Meirovitch, Fundamentals of Vibrations (McGraw-Hill, New York, 2001).

Cited By

OSA participates in CrossRef's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (7)

Fig. 1.
Fig. 1.

Schematic diagram of the near field scanning optical microscope.

Fig. 2.
Fig. 2.

The amplitude of the PZT signal measured as a function of driving frequency. (a) and (b) show symmetric and asymmetric responses with damping, respectively. The driving voltage is varied from 3mV to 15mV. A relatively high Q-factor (≥ 2500) is achieved in the case of (b) compared to (a), where the Q-factor is ~1600 and the background feedback signal is increased for higher dithering voltages.

Fig. 3.
Fig. 3.

Resonance response profiles measured as a function of driving frequency. The driving voltage is varied from 5mV to 55mV. The main resonance peak is detected around 32 760 Hz while a second peak is also detected near 28 540 Hz, respectively. Additional supplementary modes are also apparent at higher frequencies than the main resonance frequency.

Fig. 4.
Fig. 4.

Asymmetric resonance response curves simulated by a coupled two-degree-of-freedom harmonic oscillator system. Simulations of a suppressed signal in the high frequency side with K=400 for tapping mode systems(a) and in the low frequency side with K=100 for shear-force mode systems(b).

Fig. 5.
Fig. 5.

(a) Topographic NSOM images of a blue-ray optical disc obtained by utilizing an asymmetric response and (b),(c) show the cross-section view having a vertical stability of less than 2 nm.

Fig. 6.
Fig. 6.

(a) Topographic NSOM images of blue-ray optical disc obtained by utilizing a symmetric response and (b) the cross-sectional view having a vertical stability of about 10nm.

Fig. 7.
Fig. 7.

Topographic image(a) and optical image(b) of chromium mask pattern respectively and the cross-section view(c) along white dotted line.

Equations (4)

Equations on this page are rendered with MathJax. Learn more.

M x ̈ ( t ) + C x ˙ ( t ) + K x = F ( t )
X 1 ( ) = ( ω 2 m 2 + m 2 Γ 2 + k 2 + K ) F 1 + K F 2 ( ω 2 m 1 + m 1 Γ 1 + k 1 + K ) ( ω 2 m 2 + m 2 Γ 2 + k 2 + K ) K 2
X 2 ( ) = K F 1 + ( ω 2 m 1 + m 1 Γ 1 + k 1 + K ) F 2 ( ω 2 m 1 + m 1 Γ 1 + k 1 + K ) ( ω 2 m 2 + m 2 Γ 2 + k 2 + K ) K 2
X S ( ) = [ X S ( ) X ¯ S ( ) ] ½ = { [ Re X S ( ) ] 2 + [ Im X S ( ) ] 2 } ½

Metrics