Tag: EFM

Impact of annealing on electric and elastic properties of 10-nm Hf0.5Zr0.5O2 films prepared on Si by sputtering

HfO2-based films are important materials used in broad range of electronic applications from high-performance transistors and memory cells, to thermoelectric and energy harvesting elements. *

In the article “Impact of annealing on electric and elastic properties of 10-nm Hf0.5Zr0.5O2 films prepared on Si by sputtering” Leonid Bolotov, Shinji Migita, Ryouta Fujio, Manabu Ishimaru, Shogo Hatayama and Noriyuki Uchida described how they used scanning probe methods to make nanoscale comparison of chemical composition, surface morphology, the elastic modulus and the surface potential of bare 10-nm thick Hf0.5Zr0.5O2 films prepared on Si by a carbon-free sputtering process. *

NanoWorld conductive platinum iridium5 coated Pointprobe® EFM AFM probes were used for the electrostatic force microscopy (EFM). *

The composition mapping confirmed uniform distribution of Hf and Zr in the film along wafer size. Suppression of the monoclinic phase in films annealed at 600 – 800 °C had strong impact on spatial variations of film properties. Small surface roughness, large electric domain sizes (50–200 nm at 700 °C) and small fluctuations of the surface potential (40–50 meV) in Si coated with the films are appealing for gate-stack applications. Films annealed at 600-700 °C showed the elastic modulus of about 169 GPa and the ferroelectric polarization reversal at a field of ~1 MV/cm as observed by nanoscale poling with a Pt-coated scanning probe. In contrast, properties of films annealing at 800 °C were affected by growth of thick interfacial oxide layer. *

The nanoscale approach presented in the article is beneficial in optimizing of physical and mechanical properties of thin dielectric films. *

Fig. 3 from Leonid Bolotov et al. “Impact of annealing on electric and elastic properties of 10-nm Hf0.5Zr0.5O2 films prepared on Si by sputtering”: AFM topographs (a, c) and CPD maps (b, d) of 10 nm Hf0.5Zr0.5O2 films on Si: as-grown film (a, b), and annealed at 700 °C (c, d). Rectangular shapes in (c, d) outline one domain. Scale bars are 200 nm. NanoWorld conductive platinum iridium5 coated Pointprobe® EFM AFM probes were used for the electrostatic force microscopy (EFM).
Fig. 3 from Leonid Bolotov et al. “Impact of annealing on electric and elastic properties of 10-nm Hf0.5Zr0.5O2 films prepared on Si by sputtering”:
AFM topographs (a, c) and CPD maps (b, d) of 10 nm Hf0.5Zr0.5O2 films on Si: as-grown film (a, b), and annealed at 700 °C (c, d). Rectangular shapes in (c, d) outline one domain. Scale bars are 200 nm.

*Leonid Bolotov, Shinji Migita, Ryouta Fujio, Manabu Ishimaru, Shogo Hatayama and Noriyuki Uchida
Impact of annealing on electric and elastic properties of 10-nm Hf0.5Zr0.5O2 films prepared on Si by sputtering
Microelectronic Engineering, Volume 258, 1 April 2022, 111770
DOI: https://doi.org/10.1016/j.mee.2022.111770

Open Access The article “Impact of annealing on electric and elastic properties of 10-nm Hf0.5Zr0.5O2 films prepared on Si by sputtering” by Leonid Bolotov, Shinji Migita, Ryouta Fujio, Manabu Ishimaru, Shogo Hatayama and Noriyuki Uchida is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.

Determination of polarization states in (K,Na)NbO3 lead-free piezoelectric crystal

In the article “Determination of polarization states in (K,Na)NbO3lead-free piezoelectric crystal” Mao-Hua Zhang, Chengpeng Hu, Zhen Zhou, Hao Tian, Hao-Cheng Thong, Yi Xuan Liu, Xing-Yu Xu, Xiao-Qing Xi, Jing-Feng Li and Ke Wang describe how polarization switching in lead-free (K0.40Na0.60)NbO3 (KNN) single crystals was studied by switching spectroscopy piezoresponse force microscopy (SS-PFM).*

Acquisition of multiple hysteresis loops on a closely spaced square grid enables polarization switching parameters to be mapped in real space. Piezoresponse amplitude and phase hysteresis loops show collective symmetric/asymmetric characteristics, affording information regarding the switching behavior of different domains. As such, the out-of-plane polarization states of the domains, including amplitudes and phases can be determined.*

The results presented by the authors could contribute to a further understanding of the relationships between polarization switching and polarization vectors at the nanoscale, and provide a feasible method to correlate the polarization hysteresis loops in a domain under an electric field with the polarization vector states.*

PFM and SS-PFM were implemented on a commercial Atomic Force Microscope using NanoWorld PlatinumIridium coated Pointprobe® EFM AFM probes.

Fig. 1 from “Determination of polarization states in (K,Na)NbO3lead-free piezoelectric crystal” by Mao-Hua Zhang et al: PFM imaging and a schematic of tip movement during SS-PFM mapping. (a) Piezoresponse amplitude and (b) phase contrast images of the KNN single crystals. (c) In SS-PFM, local hysteresis loops are collected using a waveform at each pointon 25 × 25 mesh. The domain wall shown in Fig. 1(b) orients along [001]c.
Fig. 1 from “Determination of polarization states in (K,Na)NbO3lead-free piezoelectric crystal” by Mao-Hua Zhang et al:

*Mao-Hua Zhang, Chengpeng Hu, Zhen Zhou, Hao Tian, Hao-Cheng Thong, Yi Xuan Liu, Xing-Yu Xu, Xiao-Qing Xi, Jing-Feng Li, Ke Wang
Determination of polarization states in (K,Na)NbO3lead-free piezoelectric crystal
Journal of Advanced Ceramics2020, 9(2): 204–209
DOI: https://doi.org/10.1007/s40145-020-0360-2

Please follow this external link to read the full article: https://link.springer.com/content/pdf/10.1007/s40145-020-0360-2.pdf

Open Access The article “Determination of polarization states in (K,Na)NbO3lead-free piezoelectric crystal” Mao-Hua Zhang, Chengpeng Hu, Zhen Zhou, Hao Tian, Hao-Cheng Thong, Yi Xuan Liu, Xing-Yu Xu, Xiao-Qing Xi, Jing-Feng Li and Ke Wang is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.

Flexible 3D Electrodes of Free-Standing TiN Nanotube Arrays Grown by Atomic Layer Deposition with a Ti Interlayer as an Adhesion Promoter

Nanostructured electrodes and their flexible integrated systems have great potential for many applications, including electrochemical energy storage, electrocatalysis and solid-state memory devices, given their ability to improve faradaic reaction sites by large surface area. Although many processing techniques have been employed to fabricate nanostructured electrodes on to flexible substrates, these present limitations in terms of achieving flexible electrodes with high mechanical stability.*

In the study “Flexible 3D Electrodes of Free-Standing TiN Nanotube Arrays Grown by Atomic Layer Deposition with a Ti Interlayer as an Adhesion Promoter” by Seokjung Yun, Sang-Joon Kim, Jaesung Youn, Hoon Kim, Jeongjae Ryu, Changdeuck Bae, Kwangsoo No and Seungbum Hong, the adhesion, mechanical properties and flexibility of TiN nanotube arrays on a Pt substrate were improved using a Ti interlayer. Highly ordered and well aligned TiN nanotube arrays were fabricated on a Pt substrate using a template-assisted method with an anodic aluminum oxide (AAO) template and atomic layer deposition (ALD) system.*

The authors show that with the use of a Ti interlayer between the TiN nanotube arrays and Pt substrate, the TiN nanotube arrays could perfectly attach to the Pt substrate without delamination and faceted phenomena. Furthermore, the I-V curve measurements confirmed that the electric contact between the TiN nanotube arrays and substrate for use as an electrode was excellent, and its flexibility was also good for use in flexible electronic devices. Future efforts will be directed toward the fabrication of embedded electrodes in flexible plastic substrates by employing the concepts demonstrated in this study.*

The presented strategy provides a new class of nanostructured 3D electrodes to overcome critical mechanical stability, thus providing a great potential platform for application in a flexible integrated device.*

Topography and transport properties were investigated using a conductive atomic force microscope with NanoWorld Pointprobe® EFM AFM probes ( Pt-coated conductive AFM tips).*

Figure 5 from “Flexible 3D Electrodes of Free-Standing TiN Nanotube Arrays Grown by Atomic Layer Deposition with a Ti Interlayer as an Adhesion Promoter” by Seokjung Yun et al.:
Analysis of TiN NTs/ Ti / Pt samples (a) XRD, (b) schematic of C-AFM setup, (c) AFM height image, and (d) local I-V curve by C-AFM.

*Seokjung Yun, Sang-Joon Kim, Jaesung Youn, Hoon Kim, Jeongjae Ryu, Changdeuck Bae, Kwangsoo No and Seungbum Hong
Flexible 3D Electrodes of Free-Standing TiN Nanotube Arrays Grown by Atomic Layer Deposition with a Ti Interlayer as an Adhesion Promoter
Nanomaterials 2020, 10, 409
DOI: 10.3390/nano10030409

Please follow this external link for access to the full article: https://doi.org/10.3390/nano10030409

Open Access The article “Flexible 3D Electrodes of Free-Standing TiN Nanotube Arrays Grown by Atomic Layer Deposition with a Ti Interlayer as an Adhesion Promoter“ by Seokjung Yun, Sang-Joon Kim, Jaesung Youn, Hoon Kim, Jeongjae Ryu, Changdeuck Bae, Kwangsoo No and Seungbum Hong is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.