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Understanding Current Instabilities in Conductive Atomic Force Microscopy
Conductive atomic force microscopy (CAFM) is one of the most powerful techniques in studying the electrical properties of various materials at the nanoscale. However, understanding current fluctuations within one study (due to degradation of the probe tips) and from one study to another (due to the...
Autores principales: | , , , , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
MDPI
2019
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6384822/ https://www.ncbi.nlm.nih.gov/pubmed/30717254 http://dx.doi.org/10.3390/ma12030459 |
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author | Jiang, Lanlan Weber, Jonas Puglisi, Francesco Maria Pavan, Paolo Larcher, Luca Frammelsberger, Werner Benstetter, Guenther Lanza, Mario |
author_facet | Jiang, Lanlan Weber, Jonas Puglisi, Francesco Maria Pavan, Paolo Larcher, Luca Frammelsberger, Werner Benstetter, Guenther Lanza, Mario |
author_sort | Jiang, Lanlan |
collection | PubMed |
description | Conductive atomic force microscopy (CAFM) is one of the most powerful techniques in studying the electrical properties of various materials at the nanoscale. However, understanding current fluctuations within one study (due to degradation of the probe tips) and from one study to another (due to the use of probe tips with different characteristics), are still two major problems that may drive CAFM researchers to extract wrong conclusions. In this manuscript, these two issues are statistically analyzed by collecting experimental CAFM data and processing them using two different computational models. Our study indicates that: (i) before their complete degradation, CAFM tips show a stable state with degraded conductance, which is difficult to detect and it requires CAFM tip conductivity characterization before and after the CAFM experiments; and (ii) CAFM tips with low spring constants may unavoidably lead to the presence of a ~1.2 nm thick water film at the tip/sample junction, even if the maximum contact force allowed by the setup is applied. These two phenomena can easily drive CAFM users to overestimate the properties of the samples under test (e.g., oxide thickness). Our study can help researchers to better understand the current shifts that were observed during their CAFM experiments, as well as which probe tip to use and how it degrades. Ultimately, this work may contribute to enhancing the reliability of CAFM investigations. |
format | Online Article Text |
id | pubmed-6384822 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2019 |
publisher | MDPI |
record_format | MEDLINE/PubMed |
spelling | pubmed-63848222019-02-23 Understanding Current Instabilities in Conductive Atomic Force Microscopy Jiang, Lanlan Weber, Jonas Puglisi, Francesco Maria Pavan, Paolo Larcher, Luca Frammelsberger, Werner Benstetter, Guenther Lanza, Mario Materials (Basel) Article Conductive atomic force microscopy (CAFM) is one of the most powerful techniques in studying the electrical properties of various materials at the nanoscale. However, understanding current fluctuations within one study (due to degradation of the probe tips) and from one study to another (due to the use of probe tips with different characteristics), are still two major problems that may drive CAFM researchers to extract wrong conclusions. In this manuscript, these two issues are statistically analyzed by collecting experimental CAFM data and processing them using two different computational models. Our study indicates that: (i) before their complete degradation, CAFM tips show a stable state with degraded conductance, which is difficult to detect and it requires CAFM tip conductivity characterization before and after the CAFM experiments; and (ii) CAFM tips with low spring constants may unavoidably lead to the presence of a ~1.2 nm thick water film at the tip/sample junction, even if the maximum contact force allowed by the setup is applied. These two phenomena can easily drive CAFM users to overestimate the properties of the samples under test (e.g., oxide thickness). Our study can help researchers to better understand the current shifts that were observed during their CAFM experiments, as well as which probe tip to use and how it degrades. Ultimately, this work may contribute to enhancing the reliability of CAFM investigations. MDPI 2019-02-01 /pmc/articles/PMC6384822/ /pubmed/30717254 http://dx.doi.org/10.3390/ma12030459 Text en © 2019 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). |
spellingShingle | Article Jiang, Lanlan Weber, Jonas Puglisi, Francesco Maria Pavan, Paolo Larcher, Luca Frammelsberger, Werner Benstetter, Guenther Lanza, Mario Understanding Current Instabilities in Conductive Atomic Force Microscopy |
title | Understanding Current Instabilities in Conductive Atomic Force Microscopy |
title_full | Understanding Current Instabilities in Conductive Atomic Force Microscopy |
title_fullStr | Understanding Current Instabilities in Conductive Atomic Force Microscopy |
title_full_unstemmed | Understanding Current Instabilities in Conductive Atomic Force Microscopy |
title_short | Understanding Current Instabilities in Conductive Atomic Force Microscopy |
title_sort | understanding current instabilities in conductive atomic force microscopy |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6384822/ https://www.ncbi.nlm.nih.gov/pubmed/30717254 http://dx.doi.org/10.3390/ma12030459 |
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