Tip sample interactions in scanning probe microscopy

Project Description

The effect of tip sample interactions on dimensional metrology using scanning probe microscopes is still to be quantified and remains a small but important source of uncertainty.

The NPL and PTB have jointly developing an atomic force microscope for studying tip sample interactions and their effects on dimensional measurements made using scanning probe microscopes. The microscope has the potential to be combined with an x-ray interferometer when high lateral resolution is required. The two partners will work together over the next few years to quantify the effect of these interactions in the various modes of operation of AFMs.

2006-04-24 CMI has joined the project, bringing mathematical modelling expertise.

This work builds on that performed in EUROMET project 659.
Other actively involved partners would be welcome.

Final Report 2016-10-10

This project has been running since 2005 and initially covered a broad framework of collaboration between NPL and PTB in the subject field of scanning probe microscopy. The project was extended in 2006 by including CMI as a collaborator. Project highlights include:

• Tip-sample AFM developed at PTB jointly with NPL scientist and delivered to NPL.
• Paper describing instrument published in Meas. Sci. Technol. 18 (2007) 350–359.
• Basis for ERA-NET+ project TP3/2.1
• Ludger Koenders (PTB) visited Andrew Yacoot (NPL) for 1 week: modelling of performance of fibre interferometer, effect of tip shape on step height measurements, measurements of effect of different contact forces on Cr/glass samples.
• Andrew Yacoot & Petr Klapetek (CMI) visited PTB for 2 weeks to discuss areas for collaboration: also Andrew Yacoot compared commercial fibre interferometer vs PTB/NPL design, Petr Klapetek analysed Andrew Yacoot’s tip wear data.
• J. Phys. D review paper on AFM tips & cantilevers published by Andrew Yacoot & Ludger Koenders.
• Ludger Koenders and  Andrew Yacoot published an invited ‘Perspectives’ article for Meas.Sci. Technol. 22 (2011) 22001.
• Petr Klapetek visited NPL, more work was done to error map stages and a collaboration was been started with The University of Bristol on Error mapping High Speed AFM stages.
• A paper with initial results was submitted to Meas. Sci. Technol.
• EMRP project “6 DOF” successfully bid within the EMRP Industry call.
• Further visits of Ludger Koenders & Petre Klapetek to NPL took place, work included modelling of humidity effects and traceability of atomic steps using tip sample interaction AFM.
• Petr Klapetek visited Andrew Yacoot for 4 weeks Jan-Feb 2010. Further measurements and analysis of calibration data for measurements of errors in 3D scanning systems. Paper submitted to Meas. Sci. Technol.
• Andrew Yacoot & Ludger Koenders started writing invited ‘Perspectives’article for Meas. Sci. Technol.
• Ludger Koenders visited NPLfor further investigation of mono atomic steps on silicon.
• The invited ‘Perspectives’article for Meas.Sci. Technol. was been completed and submitted; the paper was then published.
•  A joint paper on stage error mapping has been published in Meas.Sci. Technol.
• Ongoing work continued, mainly concerned with setting up, winning and delivering EMRP projects:MEchProNo, Scatterometry, and 6DoF.
   

Further collaboration will continue in the future, mainly under EMPIR projects, and with other informal secondments, so the original project's aims have been achieved.