Resonant controller for fast atomic force microscopy

The imaging performance of the atomic force microscope (AFM) in higher scanning speed is limited to the one percent of the first resonant frequency of it's scanning unit i.e., piezoelectric tube scanner (PTS). In order to speed up the functioning of the AFM for high speed imaging, a resonant controller with an integral action has been applied in the both x and y axis of the PTS for damping the resonant mode of the scanner and improve the tracking performance. The overall closed-loop system with this scheme has higher bandwidth with improved gain and phase margin than the existing PI controller. It can reduce the cross coupling of the scanner and allows faster scanning. To measure the performance improvement of the proposed scheme a comparison has been made between the proposed controller scanned image and the existing AFM PI controller scanned image.

[1]  S. O. Reza Moheimani,et al.  Sensor-less Vibration Suppression and Scan Compensation for Piezoelectric Tube Nanopositioners , 2005, Proceedings of the 44th IEEE Conference on Decision and Control.

[2]  B. Bhikkaji,et al.  Integral Resonant Control of a Piezoelectric Tube Actuator for Fast Nanoscale Positioning , 2008, IEEE/ASME Transactions on Mechatronics.

[3]  O. Wood,et al.  Novel alignment system for imprint lithography , 2000 .

[4]  D. Croft,et al.  Creep, hysteresis, and vibration compensation for piezoactuators: atomic force microscopy application , 2000, Proceedings of the 2000 American Control Conference. ACC (IEEE Cat. No.00CH36334).

[5]  Qingze Zou,et al.  Iterative control of dynamics-coupling-caused errors in piezoscanners during high-speed AFM operation , 2005, IEEE Transactions on Control Systems Technology.

[6]  J. An,et al.  Fabrication HfOx nanopatterns by atomic force microscopy lithography , 2008, 2008 IEEE International Conference on Electron Devices and Solid-State Circuits.

[7]  S. Devasia,et al.  Feedforward control of piezoactuators in atomic force microscope systems , 2009, IEEE Control Systems.

[8]  S O Reza Moheimani,et al.  Making a commercial atomic force microscope more accurate and faster using positive position feedback control. , 2009, The Review of scientific instruments.

[9]  Hemanshu R. Pota,et al.  Resonant controllers for smart structures , 2002 .

[10]  Sumeet S Aphale,et al.  A New Method for Robust Damping and Tracking Control of Scanning Probe Microscope Positioning Stages , 2010, IEEE Transactions on Nanotechnology.

[11]  Santosh Devasia,et al.  A Survey of Control Issues in Nanopositioning , 2007, IEEE Transactions on Control Systems Technology.

[12]  S.O. Reza Moheimani,et al.  Resonant controllers for flexible structures , 1999, Proceedings of the 38th IEEE Conference on Decision and Control (Cat. No.99CH36304).

[13]  M. Taylor Dynamics of piezoelectric tube scanners for scanning probe microscopy , 1993 .

[14]  Toshio Ando,et al.  Active damping of the scanner for high-speed atomic force microscopy , 2005 .

[15]  G. Schitter Advanced Mechanical Design and Control Methods for Atomic Force Microscopy in Real-Time , 2007, 2007 American Control Conference.

[16]  Y. Yam,et al.  Frequency Domain Identification Experiment on a Large Flexible Structure , 1989, 1989 American Control Conference.

[17]  G. Binnig,et al.  Scanning tunneling microscopy-from birth to adolescence , 1987 .

[18]  I. Petersen,et al.  Robust H∞ control in fast atomic force microscopy , 2011, Proceedings of the 2011 American Control Conference.