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Title: Optimizing qPlus sensor assemblies for simultaneous scanning tunneling and noncontact atomic force microscopy operation based on finite element method analysis

Abstract

Quartz tuning forks that have a probe tip attached to the end of one of its prongs while the other prong is arrested to a holder (“qPlus” configuration) have gained considerable popularity in recent years for high-resolution atomic force microscopy imaging. The small size of the tuning forks and the complexity of the sensor architecture, however, often impede predictions on how variations in the execution of the individual assembly steps affect the performance of the completed sensor. Extending an earlier study that provided numerical analysis of qPlus-style setups without tips, this work quantifies the influence of tip attachment on the operational characteristics of the sensor. The results using finite element modeling show in particular that for setups that include a metallic tip that is connected via a separate wire to enable the simultaneous collection of local forces and tunneling currents, the exact realization of this wire connection has a major effect on sensor properties such as spring constant, quality factor, resonance frequency, and its deviation from an ideal vertical oscillation.

Authors:
 [1];  [1]
  1. Yale Univ., New Haven, CT (United States)
Publication Date:
Research Org.:
Yale Univ., New Haven, CT (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1426778
Grant/Contract Number:
sC0016179
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Beilstein Journal of Nanotechnology
Additional Journal Information:
Journal Volume: 8; Journal ID: ISSN 2190-4286
Publisher:
Beilstein Institute
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; force sensor; noncontact atomic force microscopy; quartz tuning forks; scanning tunneling microscopy; self-sensing probe

Citation Formats

Dagdeviren, Omur E., and Schwarz, Udo D.. Optimizing qPlus sensor assemblies for simultaneous scanning tunneling and noncontact atomic force microscopy operation based on finite element method analysis. United States: N. p., 2017. Web. doi:10.3762/bjnano.8.70.
Dagdeviren, Omur E., & Schwarz, Udo D.. Optimizing qPlus sensor assemblies for simultaneous scanning tunneling and noncontact atomic force microscopy operation based on finite element method analysis. United States. doi:10.3762/bjnano.8.70.
Dagdeviren, Omur E., and Schwarz, Udo D.. Mon . "Optimizing qPlus sensor assemblies for simultaneous scanning tunneling and noncontact atomic force microscopy operation based on finite element method analysis". United States. doi:10.3762/bjnano.8.70. https://www.osti.gov/servlets/purl/1426778.
@article{osti_1426778,
title = {Optimizing qPlus sensor assemblies for simultaneous scanning tunneling and noncontact atomic force microscopy operation based on finite element method analysis},
author = {Dagdeviren, Omur E. and Schwarz, Udo D.},
abstractNote = {Quartz tuning forks that have a probe tip attached to the end of one of its prongs while the other prong is arrested to a holder (“qPlus” configuration) have gained considerable popularity in recent years for high-resolution atomic force microscopy imaging. The small size of the tuning forks and the complexity of the sensor architecture, however, often impede predictions on how variations in the execution of the individual assembly steps affect the performance of the completed sensor. Extending an earlier study that provided numerical analysis of qPlus-style setups without tips, this work quantifies the influence of tip attachment on the operational characteristics of the sensor. The results using finite element modeling show in particular that for setups that include a metallic tip that is connected via a separate wire to enable the simultaneous collection of local forces and tunneling currents, the exact realization of this wire connection has a major effect on sensor properties such as spring constant, quality factor, resonance frequency, and its deviation from an ideal vertical oscillation.},
doi = {10.3762/bjnano.8.70},
journal = {Beilstein Journal of Nanotechnology},
number = ,
volume = 8,
place = {United States},
year = {Mon Mar 20 00:00:00 EDT 2017},
month = {Mon Mar 20 00:00:00 EDT 2017}
}

Journal Article:
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  • Based on a two-prong type quartz tuning fork, a force sensor with a high Q factor, which we call a retuned fork sensor, was developed for non-contact atomic force microscopy (nc-AFM) with atomic resolution. By cutting a small notch and attaching an AFM tip to one prong, its resonance frequency can be retuned to that of the other intact prong. In balancing the two prongs in this manner, a high Q factor (>50 000 in ultrahigh vacuum) is obtained for the sensor. An atomic resolution image of the Si(111)-7 × 7 surface was demonstrated using an nc-AFM with the sensor. The dependence ofmore » the Q factor on resonance frequency of the sensor and the long-range force between tip and sample were measured and analyzed in view of the various dissipation channels. Dissipation in the signal detection circuit turned out to be mainly limited by the total Q factor of the nc-AFM system.« less
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