On the Limits of Scanning Thermal Microscopy of Ultrathin Films

Heat transfer processes in micro- and nanoscale devices have become more and more important during the last decades. Scanning thermal microscopy (SThM) is an atomic force microscopy (AFM) based method for analyzing local thermal conductivities of layers with thicknesses in the range of several nm to µm. In this work, we investigate ultrathin films of hexagonal boron nitride (h-BN), copper iodide in zincblende structure (γ-CuI) and some test sample structures fabricated of silicon (Si) and silicon dioxide (SiO2) using SThM. Specifically, we analyze and discuss the influence of the sample topography, the touching angle between probe tip and sample, and the probe tip temperature on the acquired results. In essence, our findings indicate that SThM measurements include artefacts that are not associated with the thermal properties of the film under investigation. We discuss possible ways of influence, as well as the magnitudes involved. Furthermore, we suggest necessary measuring conditions that make qualitative SThM measurements of ultrathin films of h-BN with thicknesses at or below 23 nm possible.

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Scanning Thermal Microscopy of Ultrathin Films: Numerical Studies Regarding Cantilever Displacement, Thermal Contact Areas, Heat Fluxes, and Heat Distribution

Nanomaterials ◽

10.3390/nano11020491 ◽

2021 ◽

Vol 11 (2) ◽

pp. 491

Author(s):

Christoph Metzke ◽

Fabian Kühnel ◽

Jonas Weber ◽

Günther Benstetter

Keyword(s):

Thermal Properties ◽

Ultrathin Films ◽

Hexagonal Boron Nitride ◽

Thermal Contact ◽

Heat Transfer Process ◽

Heat Propagation ◽

Heat Fluxes ◽

Detailed Knowledge ◽

Scanning Thermal Microscopy ◽

Thermal Microscopy

New micro- and nanoscale devices require electrically isolating materials with specific thermal properties. One option to characterize these thermal properties is the atomic force microscopy (AFM)-based scanning thermal microscopy (SThM) technique. It enables qualitative mapping of local thermal conductivities of ultrathin films. To fully understand and correctly interpret the results of practical SThM measurements, it is essential to have detailed knowledge about the heat transfer process between the probe and the sample. However, little can be found in the literature so far. Therefore, this work focuses on theoretical SThM studies of ultrathin films with anisotropic thermal properties such as hexagonal boron nitride (h-BN) and compares the results with a bulk silicon (Si) sample. Energy fluxes from the probe to the sample between 0.6 µW and 126.8 µW are found for different cases with a tip radius of approximately 300 nm. A present thermal interface resistance (TIR) between bulk Si and ultrathin h-BN on top can fully suppress a further heat penetration. The time until heat propagation within the sample is stationary is found to be below 1 µs, which may justify higher tip velocities in practical SThM investigations of up to 20 µms−1. It is also demonstrated that there is almost no influence of convection and radiation, whereas a possible TIR between probe and sample must be considered.

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CTE-matched Cantilevers for Improved Heated Atomic Force Microscopy and Passive-mode Scanning Thermal Microscopy

2018 17th IEEE Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (ITherm) ◽

10.1109/itherm.2018.8419532 ◽

2018 ◽

Author(s):

Darin J. Sharar ◽

Adam A. Wilson

Keyword(s):

Atomic Force Microscopy ◽

Scanning Thermal Microscopy ◽

Passive Mode ◽

Thermal Microscopy ◽

Force Microscopy ◽

Atomic Force

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Scanning thermal microscopy and atomic force microscopy studies of laser-induced deposited metal lines

Applied Surface Science ◽

10.1016/s0169-4332(97)00231-6 ◽

1997 ◽

Vol 120 (1-2) ◽

pp. 149-158 ◽

Cited By ~ 6

Author(s):

L Zhou ◽

G.Q Xu ◽

S.F.Y Li ◽

P.K.H Ho ◽

P.C Zhang ◽

...

Keyword(s):

Atomic Force Microscopy ◽

Scanning Thermal Microscopy ◽

Thermal Microscopy ◽

Force Microscopy ◽

Atomic Force ◽

Deposited Metal

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Lateral Size of Self-Patterned Nanostructures Controlled by Multi-Step Deposition

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.106.117 ◽

2005 ◽

Vol 106 ◽

pp. 117-122 ◽

Cited By ~ 3

Author(s):

Izabela Szafraniak ◽

Dietrich Hesse ◽

Marin Alexe

Keyword(s):

Electron Microscopy ◽

Ultrathin Films ◽

Lateral Size ◽

X Ray Diffraction ◽

X Ray ◽

Force Microscopy ◽

Atomic Force ◽

Non Volatile Memory ◽

Ferroelectric Capacitors ◽

Scanning Electron

Self-patterning presents an appealing alternative to lithography for the production of arrays of nanoscale ferroelectric capacitors for use in high density non-volatile memory devices. Recently a self-patterning method, based on the use of the instability of ultrathin films during hightemperature treatments, was used to fabricate nanosized ferroelectrics. This paper reports the use of the method for the preparation of PZT nanoislands on different single crystalline substrates - SrTiO3, MgO and LaAlO3. Moreover, a multi-step deposition procedure in order to control lateral the dimension of the crystals was introduced. The nanostructures obtained were studied by atomic force microscopy, scanning electron microscopy and X-ray diffraction.

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Atomic Force Microscopy study of hexagonal boron nitride film growth on 6H-SiC (0001)

phys stat sol (a) ◽

10.1002/pssa.200590001 ◽

2005 ◽

Vol 202 (1) ◽

pp. 3-3 ◽

Cited By ~ 1

Author(s):

Wei Chen ◽

Kian Ping Loh ◽

Ming Lin ◽

Rong Liu ◽

Andrew T. S. Wee

Keyword(s):

Atomic Force Microscopy ◽

Boron Nitride ◽

Film Growth ◽

Hexagonal Boron Nitride ◽

Microscopy Study ◽

Nitride Film ◽

Atomic Force Microscopy Study ◽

Force Microscopy ◽

Atomic Force

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Self-assembly layer-by-layer fabrication using porphyrin dye anion and polycation

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424609001030 ◽

2009 ◽

Vol 13 (07) ◽

pp. 774-778 ◽

Cited By ~ 1

Author(s):

Byung-Soon Kim ◽

Young-A Son

Keyword(s):

Ultrathin Films ◽

Self Assembly ◽

Film Surface ◽

Layer By Layer ◽

Preparation Technique ◽

Force Microscopy ◽

Atomic Force ◽

Diallyldimethylammonium Chloride ◽

Afm Analysis ◽

Progressive Growth

In this study, self-assembled alternating film using poly(diallyldimethylammonium chloride) (PDDAC) and meso-tetrakis(4-carboxyphenyl)porphyrin (MTCP) was prepared as a multilayer deposition on glass substrate. This preparation technique for dye deposition may provide new feasibilities to achieve the manufacture of ultrathin films for nanotechnology application. The deposition films were characterized by UV-vis spectrophotometer and Atomic Force Microscopy (AFM) analysis. The results of UV-vis spectra showed that the absorbance characteristic of the multilayer films linearly increased with an increased number of PDDAC and MTCP bilayers. AFM analysis showed the film surface was relatively uniform and the progressive growth of layers was determined.

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Hexagonal Boron Nitride Tunnel Barriers Grown on Graphite by High Temperature Molecular Beam Epitaxy

Scientific Reports ◽

10.1038/srep34474 ◽

2016 ◽

Vol 6 (1) ◽

Cited By ~ 33

Author(s):

Yong-Jin Cho ◽

Alex Summerfield ◽

Andrew Davies ◽

Tin S. Cheng ◽

Emily F. Smith ◽

...

Keyword(s):

Atomic Force Microscopy ◽

High Temperature ◽

Molecular Beam Epitaxy ◽

Boron Nitride ◽

Photoelectron Spectroscopy ◽

Molecular Beam ◽

Hexagonal Boron Nitride ◽

Graphite Substrate ◽

Force Microscopy ◽

Atomic Force

Abstract We demonstrate direct epitaxial growth of high-quality hexagonal boron nitride (hBN) layers on graphite using high-temperature plasma-assisted molecular beam epitaxy. Atomic force microscopy reveals mono- and few-layer island growth, while conducting atomic force microscopy shows that the grown hBN has a resistance which increases exponentially with the number of layers, and has electrical properties comparable to exfoliated hBN. X-ray photoelectron spectroscopy, Raman microscopy and spectroscopic ellipsometry measurements on hBN confirm the formation of sp2-bonded hBN and a band gap of 5.9 ± 0.1 eV with no chemical intermixing with graphite. We also observe hexagonal moiré patterns with a period of 15 nm, consistent with the alignment of the hBN lattice and the graphite substrate.

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Plastic Deformation Macrolocalization. Local Stresses and Fracture in Ultrafine Grain Titanium

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.682.351 ◽

2014 ◽

Vol 682 ◽

pp. 351-356 ◽

Cited By ~ 7

Author(s):

Vladimir Danilov ◽

Galina Shlyakhova ◽

Boris Semukhin

Keyword(s):

Plastic Deformation ◽

Quantitative Assessment ◽

Test Sample ◽

Ultrafine Grain ◽

Material Structure ◽

X Ray ◽

Force Microscopy ◽

Qualitative And Quantitative ◽

Atomic Force ◽

Local Stresses

The process of plastic deformation in ultrafine grain titanium is considered. Using the methods of speckle photography and X-ray diffractometry, the distributions of local strains and of local elastic distortions were examined for the test sample work. It is shown that the method of atomic-force microscopy can be used effectively for qualitative and quantitative assessment of ultrafine grain material structure.

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Characterization of Asymmetric Polydiacetylene Ultrathin Films

MRS Proceedings ◽

10.1557/proc-382-265 ◽

1995 ◽

Vol 382 ◽

Author(s):

D. W. Cheong ◽

V. Shivshankar ◽

H. C. Wang ◽

C. M. Sung ◽

J. Kumar ◽

...

Keyword(s):

Ultrathin Films ◽

Second Harmonic ◽

Film Deposition ◽

Asymmetric Structure ◽

Blodgett Film ◽

Force Microscopy ◽

Langmuir Blodgett ◽

Atomic Force ◽

Ft Ir

ABSTRACTNonlinear optical (NLO) ultrathin films of a preforrned asymmetric polydiacetylene have been fabricated by Z-type Langmuir-Blodgett film deposition from the air-water interface. Induced in-plane orientation of the polydiacetylene backbone on the substrates has been confirmed by UV/Vis, FT-IR dichroism, and degenerate four wave mixing (DFWM) studies. All the measurements indicate that the backbone is prefe rentially oriented along the dipping direction. Second harmonic generation study suggests that the LB multilayers form an asymmetric structure (Z-type) due to the accumulation of 2-dimensional ordered monolayer and the dominant induced second order polarization is in the plane of the film. The film morphology and molecular orientation have been investigated by atomic force microscopy (AFM).

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