JoVE Logo
Faculty Resource Center

Sign In





Representative Results






Active Probe Atomic Force Microscopy with Quattro-Parallel Cantilever Arrays for High-Throughput Large-Scale Sample Inspection

Published: June 13th, 2023



1Mechatronics Research Lab, Department of Mechanical Engineering, Massachusetts Institute of Technology, 2Mechatronics Group, Department of Mechanical Engineering, Ilmenau University of Technology, 3Production and Precision Measurement Technology Group, Institute of Process Measurement and Sensor Technology, Ilmenau University of Technology, 4Nanoscale Systems Group, Institute of Process Measurement and Sensor Technology, Ilmenau University of Technology, 5nano analytik GmbH

Large-scale sample inspection with nanoscale resolution has a wide range of applications, especially for nanofabricated semiconductor wafers. Atomic force microscopes can be a great tool for this purpose, but are limited by their imaging speed. This work utilizes parallel active cantilever arrays in AFMs to enable high-throughput and large-scale inspections.

An Atomic Force Microscope (AFM) is a powerful and versatile tool for nanoscale surface studies to capture 3D topography images of samples. However, due to their limited imaging throughput, AFMs have not been widely adopted for large-scale inspection purposes. Researchers have developed high-speed AFM systems to record dynamic process videos in chemical and biological reactions at tens of frames per second, at the cost of a small imaging area of up to several square micrometers. In contrast, inspecting large-scale nanofabricated structures, such as semiconductor wafers, requires nanoscale spatial resolution imaging of a static sample over hundreds of square centimeters with high productivity. Conventional AFMs use a single passive cantilever probe with an optical beam deflection system, which can only collect one pixel at a time during AFM imaging, resulting in low imaging throughput. This work utilizes an array of active cantilevers with embedded piezoresistive sensors and thermomechanical actuators, which allows simultaneous multi-cantilever operation in parallel operation for increased imaging throughput. When combined with large-range nano-positioners and proper control algorithms, each cantilever can be individually controlled to capture multiple AFM images. With data-driven post-processing algorithms, the images can be stitched together, and defect detection can be performed by comparing them to the desired geometry. This paper introduces principles of the custom AFM using the active cantilever arrays, followed by a discussion on practical experiment considerations for inspection applications. Selected example images of silicon calibration grating, highly-oriented pyrolytic graphite, and extreme ultraviolet lithography masks are captured using an array of four active cantilevers ("Quattro") with a 125 µm tip separation distance. With more engineering integration, this high-throughput, large-scale imaging tool can provide 3D metrological data for extreme ultraviolet (EUV) masks, chemical mechanical planarization (CMP) inspection, failure analysis, displays, thin-film step measurements, roughness measurement dies, and laser-engraved dry gas seal grooves.

Atomic force microscopes (AFMs) can capture 3D topography images with nanoscale spatial resolution. Researchers have extended the capability of AFMs to create sample property maps in mechanical, electrical, magnetic, optical, and thermal domains. In the meantime, improving imaging throughput has also been the focus of research to adapt AFMs to new experimental needs. There are primarily two application domains for high-throughput AFM imaging: the first category is high-speed imaging of a small area to capture dynamic changes in the sample due to biological or chemical reactions1,2; the second category is for h....

Log in or to access full content. Learn more about your institution’s access to JoVE content here

1. Sample preparation for large-scale inspection

  1. Prepare the sample with a suitable size for the AFM (see Table of Materials).
    NOTE: Wafer-shape samples with an in-plane diameter from 75 mm to 300 mm and an expected out-of-plane height variation below 200 µm can fit on the AFM sample stage. In this study, an extreme ultraviolet (EUV) mask on a 4 inch wafer is used (see Table of Materials).
  2. Clean the sample to remove contaminants and.......

Log in or to access full content. Learn more about your institution’s access to JoVE content here

To demonstrate the effectiveness of AFM large-range imaging using parallel active cantilevers for topography imaging, the stitched images of a calibration grating, taken by four cantilevers operated in parallel, are shown in Figure 2. The silicon wafer calibration structure has 45 µm long features with a height of 14 nm. Each cantilever covers an area of 125 µm by 125 µm, which gives a stitched panoramic image of 500 µm by 125 µm. The scanning speed was set to 10 lin.......

Log in or to access full content. Learn more about your institution’s access to JoVE content here

As demonstrated in the representative results, an active cantilever array can be used to capture multiple images of a static sample in parallel. This scalable setup can significantly improve the imaging throughput of large-area samples, making it suitable for inspecting nanofabricated devices on semiconductor wafers. The technique is also not limited to man-made structures; as long as the topography variation within a group of active cantilevers is not too large for the cantilever array to handle, high-throughput imaging.......

Log in or to access full content. Learn more about your institution’s access to JoVE content here

The authors Ivo W. Rangelow and Thomas Sattel would like to acknowledge the German Federal Ministry of Education and Research (BMBF) and the German Federal Ministry of Economics Affairs and Climate Action (BMWK) for supporting parts of the presented methods by funding the projects FKZ:13N16580 "Active Probes with diamond tip for quantum metrology and nanofabrication" within the research line KMU-innovativ: Photonics and Quantum Technologies and KK5007912DF1 "Conjungate Nano-Positioner-Scanner for fast and large metrological tasks in Atomic Force Microscopy" within the funding line Central Innovation Program for small and medium sized industries (ZIM). ....

Log in or to access full content. Learn more about your institution’s access to JoVE content here

NameCompanyCatalog NumberComments
Active-Cantilever nano analytik GmbHAC-10-2012AFM Probe
E-BeamEBX-30, INC012323-15Mask patterning instrument
Highly Oriented Pyrolytic Graphite – HOPGTED PELLA, INC626-10AFM calibration sample
Mask SampleNanda Technologies GmbHTest substrateEUV Mask Sample substrate
NANO-COMPAS-PRO nano analytik GmbH23-2016AFM Software
nanoMetronom 20nano analytik GmbH1-343-2020AFM Instrument

  1. Ando, T. High-speed atomic force microscopy and its future prospects. Biophysical Reviews. 10 (2), 285-292 (2018).
  2. Soltani Bozchalooi, I., Careaga Houck, A., AlGhamdi, J. M., Youcef-Toumi, K. Design and control of multi-actuated atomic force microscope for large-range and high-speed imaging. Ultramicroscopy. 160, 213-224 (2016).
  3. Sohn, Y., Ryu, S., Yang, Y. Semiconductor technology challenges in high volume manufacturing of semiconductors. Microscopy and Microanalysis. 28, 800-801 (2022).
  4. Ebayyeh, A. A. R. M. A., Mousavi, A. A review and analysis of automatic optical inspection and quality monitoring methods in electronics industry. IEEE Access. 8, 183192-183271 (2020).
  5. Nakamae, K. Electron microscopy in semiconductor inspection. Measurement Science and Technology. 32 (5), 052003 (2021).
  6. Nduhura-Munga, J., et al. A literature review on sampling techniques in semiconductor manufacturing. IEEE Transactions on Semiconductor Manufacturing. 26 (2), 188-195 (2013).
  7. Zhang, T., et al. Correlative AFM and scanning microlens microscopy for time-efficient multiscale imaging. Advanced Science. 9 (12), 2103902 (2022).
  8. Holz, M., et al. Correlative microscopy and nanofabrication with AFM integrated with SEM. Microscopy Today. 27 (6), 24-30 (2019).
  9. Yang, C., Xia, F., Wang, Y., Truncale, S., Youcef-Toumi, K. Design and control of a multi-actuated nanopositioning stage with stacked structure. 2019 American Control Conference (ACC). , 3782-3788 (2019).
  10. Xia, F., Truncale, S., Wang, Y., Youcef-Toumi, K. Design and control of a multi-actuated high-bandwidth and large-range scanner for atomic force microscopy. 2018 Annual American Control Conference (ACC). , 4330-4335 (2018).
  11. Yong, Y. K., Moheimani, S. O. R., Kenton, B. J., Leang, K. K. Invited review article: high-speed flexure-guided nanopositioning: mechanical design and control issues. The Review of Scientific Instruments. 83 (12), 121101 (2012).
  12. Wang, J. Y., Mullin, N., Hobbs, J. K. High-speed large area atomic force microscopy using a quartz resonator. Nanotechnology. 29 (33), 335502 (2018).
  13. Yang, C., et al. Charge controller with decoupled and self-compensating configurations for linear operation of piezoelectric actuators in a wide bandwidth. IEEE Transactions on Industrial Electronics. 66 (7), 5392-5402 (2019).
  14. Yang, C., Xia, F., Wang, Y., Youcef-Toumi, K. Comprehensive study of charge-based motion control for piezoelectric nanopositioners: Modeling, instrumentation and controller design. Mechanical Systems and Signal Processing. 166, 108477 (2022).
  15. Xia, F., Yang, C., Wang, Y., Youcef-Toumi, K. Bandwidth based repetitive controller design for a modular multi-actuated AFM scanner. 2019 American Control Conference (ACC). , 3776-3781 (2019).
  16. Ahmad, A., Schuh, A., Rangelow, I. W. Adaptive AFM scan speed control for high aspect ratio fast structure tracking. The Review of Scientific Instruments. 85 (10), 103706 (2014).
  17. Coskun, M. B., Alemansour, H., Fowler, A. G., Maroufi, M., Moheimani, S. O. R. Q control of an active AFM cantilever with differential sensing configuration. IEEE Transactions on Control Systems Technology. 27 (5), 2271-2278 (2019).
  18. Xia, F., Mayborne, M. P., Ma, Q., Youcef-Toumi, K. Physical intelligence in the metaverse: mixed reality scale models for twistronics and atomic force microscopy. 2022 IEEE/ASME International Conference on Advanced Intelligent Mechatronics (AIM). , 1722-1729 (2022).
  19. Xia, F., et al. A modular low-cost atomic force microscope for precision mechatronics education. Mechatronics. 76, 102550 (2021).
  20. Minne, S. C., et al. Centimeter scale atomic force microscope imaging and lithography. Applied Physics Letters. 73 (12), 1742-1744 (1998).
  21. Minne, S. C., et al. Automated parallel high-speed atomic force microscopy. Applied Physics Letters. 72 (18), 2340-2342 (1998).
  22. Ahmad, A., et al. Large area fast-AFM scanning with active "Quattro" cantilever arrays. Journal of Vacuum Science & Technology B. 34 (6), (2016).
  23. Gotszalk, T., Grabiec, P., Rangelow, I. W. Piezoresistive sensors for scanning probe microscopy. Ultramicroscopy. 82 (1), 39-48 (2000).
  24. Angelov, T., et al. Thermo-mechanical transduction suitable for high-speed scanning probe imaging and lithography. Microelectronic Engineering. 154, 1-7 (2016).
  25. Rangelow, I. W., et al. Active scanning probes: A versatile toolkit for fast imaging and emerging nanofabrication. Journal of Vacuum Science & Technology B. 35 (6), 101 (2017).
  26. Marinello, F., Bariani, P., De Chiffre, L., Hansen, H. N. Development and analysis of a software tool for stitching three-dimensional surface topography data sets. Measurement Science and Technology. 18 (5), 1404 (2007).
  27. López de la Rosa, F., Sánchez-Reolid, R., Gómez-Sirvent, J. L., Morales, R., Fernández-Caballero, A. A review on machine and deep learning for semiconductor defect classification in scanning electron microscope images. Applied Sciences. 11 (20), 9508 (2021).
  28. Holz, M., et al. High throughput AFM inspection system with parallel active cantilevers. In Photomask Technology 2019. 11148, 278-287 (2019).
  29. Gotszalk, T., Ivanov, T., Rangelow, I. Parallel SPM cantilever arrays for large area surface metrology and lithography. In Metrology, Inspection, and Process Control for Microlithography XXVIII. 9050, 274-282 (2014).
  30. Ahmad, A., et al. 13th Intl. Workshop on Nanomechanical Sensing. Quattro-Cantilever Array: Large Area and High Speed AFM Imaging and Nanolithography. , (2016).
  31. Shearer, C. J., Slattery, A. D., Stapleton, A. J., Shapter, J. G., Gibson, C. T. Accurate thickness measurement of graphene. Nanotechnology. 27 (12), 125704 (2016).
  32. Shioyama, H. The interactions of two chemical species in the interlayer spacing of graphite. Synthetic Metals. 114 (1), 1-15 (2000).
  33. Ivanova, K., et al. Scanning proximal probes for parallel imaging and lithography. Journal of Vacuum Science & Technology B. 26 (6), 2367-2373 (2008).
  34. García, R., San Paulo, A. Attractive and repulsive tip-sample interaction regimes in tapping-mode atomic force microscopy. Physical Review B. 60 (7), 4961-4967 (1999).
  35. Ruppert, M. G., Fowler, A. G., Maroufi, M., Moheimani, S. O. R. On-chip dynamic mode atomic force microscopy: a silicon-on-insulator MEMS approach. Journal of Microelectromechanical Systems. 26 (1), 215-225 (2017).

This article has been published

Video Coming Soon

JoVE Logo


Terms of Use





Copyright © 2024 MyJoVE Corporation. All rights reserved