In situ Stiffness Adjustment of AFM Probes by Two Orders of Magnitude
The choice on which type of cantilever to use for Atomic Force Microscopy (AFM) depends on the type of the experiment being done. Typically, the cantilever has to be exchanged when a different stiffness is required and the entire alignment has to be repeated. In the present work, a method to adjust...
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| Format: | Article |
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MDPI AG
2016-04-01
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| Series: | Sensors |
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| Online Access: | http://www.mdpi.com/1424-8220/16/4/523 |
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| author | Marcel Lambertus Cornelis de Laat Héctor Hugo Pérez Garza Murali Krishna Ghatkesar |
| author_facet | Marcel Lambertus Cornelis de Laat Héctor Hugo Pérez Garza Murali Krishna Ghatkesar |
| author_sort | Marcel Lambertus Cornelis de Laat |
| collection | DOAJ |
| description | The choice on which type of cantilever to use for Atomic Force Microscopy (AFM) depends on the type of the experiment being done. Typically, the cantilever has to be exchanged when a different stiffness is required and the entire alignment has to be repeated. In the present work, a method to adjust the stiffness in situ of a commercial AFM cantilever is developed. The adjustment is achieved by changing the effective length of the cantilever by electrostatic pull-in. By applying a voltage between the cantilever and an electrode (with an insulating layer at the point of contact), the cantilever snaps to the electrode, reducing the cantilever’s effective length. An analytical model was developed to find the pull-in voltage of the system. Subsequently, a finite element model was developed to study the pull-in behavior. The working principle of this concept is demonstrated with a proof-of-concept experiment. The electrode was positioned close to the cantilever by using a robotic nanomanipulator. To confirm the change in stiffness, the fundamental resonance frequency of the cantilever was measured for varying electrode positions. The results match with the theoretical expectations. The stiffness was adjusted in situ in the range of 0.2 N/m to 27 N/m, covering two orders of magnitude in one single cantilever. This proof-of-concept is the first step towards a micro fabricated prototype, that integrates the electrode positioning system and cantilever that can be used for actual AFM experiments. |
| first_indexed | 2024-04-14T07:00:19Z |
| format | Article |
| id | doaj.art-8d476a7c8723424295447e8eb247cf50 |
| institution | Directory Open Access Journal |
| issn | 1424-8220 |
| language | English |
| last_indexed | 2024-04-14T07:00:19Z |
| publishDate | 2016-04-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Sensors |
| spelling | doaj.art-8d476a7c8723424295447e8eb247cf502022-12-22T02:06:46ZengMDPI AGSensors1424-82202016-04-0116452310.3390/s16040523s16040523In situ Stiffness Adjustment of AFM Probes by Two Orders of MagnitudeMarcel Lambertus Cornelis de Laat0Héctor Hugo Pérez Garza1Murali Krishna Ghatkesar2Department of Precision and Microsystems Engineering (PME), Faculty of Mechanical, Maritime and Materials Engineering (3mE), Delft University of Technology, Mekelweg 2, 2628 CD Delft, The NetherlandsDENSsolutions BV, Informaticalaan 12, 2628ZD Delft, The NetherlandsDepartment of Precision and Microsystems Engineering (PME), Faculty of Mechanical, Maritime and Materials Engineering (3mE), Delft University of Technology, Mekelweg 2, 2628 CD Delft, The NetherlandsThe choice on which type of cantilever to use for Atomic Force Microscopy (AFM) depends on the type of the experiment being done. Typically, the cantilever has to be exchanged when a different stiffness is required and the entire alignment has to be repeated. In the present work, a method to adjust the stiffness in situ of a commercial AFM cantilever is developed. The adjustment is achieved by changing the effective length of the cantilever by electrostatic pull-in. By applying a voltage between the cantilever and an electrode (with an insulating layer at the point of contact), the cantilever snaps to the electrode, reducing the cantilever’s effective length. An analytical model was developed to find the pull-in voltage of the system. Subsequently, a finite element model was developed to study the pull-in behavior. The working principle of this concept is demonstrated with a proof-of-concept experiment. The electrode was positioned close to the cantilever by using a robotic nanomanipulator. To confirm the change in stiffness, the fundamental resonance frequency of the cantilever was measured for varying electrode positions. The results match with the theoretical expectations. The stiffness was adjusted in situ in the range of 0.2 N/m to 27 N/m, covering two orders of magnitude in one single cantilever. This proof-of-concept is the first step towards a micro fabricated prototype, that integrates the electrode positioning system and cantilever that can be used for actual AFM experiments.http://www.mdpi.com/1424-8220/16/4/523stiffnessadjustable stiffnessstiffness tuningAFMAtomic Force Microscope |
| spellingShingle | Marcel Lambertus Cornelis de Laat Héctor Hugo Pérez Garza Murali Krishna Ghatkesar In situ Stiffness Adjustment of AFM Probes by Two Orders of Magnitude Sensors stiffness adjustable stiffness stiffness tuning AFM Atomic Force Microscope |
| title | In situ Stiffness Adjustment of AFM Probes by Two Orders of Magnitude |
| title_full | In situ Stiffness Adjustment of AFM Probes by Two Orders of Magnitude |
| title_fullStr | In situ Stiffness Adjustment of AFM Probes by Two Orders of Magnitude |
| title_full_unstemmed | In situ Stiffness Adjustment of AFM Probes by Two Orders of Magnitude |
| title_short | In situ Stiffness Adjustment of AFM Probes by Two Orders of Magnitude |
| title_sort | in situ stiffness adjustment of afm probes by two orders of magnitude |
| topic | stiffness adjustable stiffness stiffness tuning AFM Atomic Force Microscope |
| url | http://www.mdpi.com/1424-8220/16/4/523 |
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