Physical vapor deposited titanium thin films for biomedical applications: Reproducibility of nanoscale surface roughness and microbial adhesion properties

2013 ◽  
Vol 280 ◽  
pp. 578-589 ◽  
Author(s):  
Claudia Lüdecke ◽  
Jörg Bossert ◽  
Martin Roth ◽  
Klaus D. Jandt
Coatings ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 413 ◽  
Author(s):  
Robert Müller ◽  
Lilit Ghazaryan ◽  
Paul Schenk ◽  
Sabrina Wolleb ◽  
Vivek Beladiya ◽  
...  

High-density ruthenium (Ru) thin films were deposited using Ru(EtCp)2 (bis(ethylcyclopentadienyl)ruthenium) and oxygen by thermal atomic layer deposition (ALD) and compared to magnetron sputtered (MS) Ru coatings. The ALD Ru film growth and surface roughness show a significant temperature dependence. At temperatures below 200 °C, no deposition was observed on silicon and fused silica substrates. With increasing deposition temperature, the nucleation of Ru starts and leads eventually to fully closed, polycrystalline coatings. The formation of blisters starts at temperatures above 275 °C because of poor adhesion properties, which results in a high surface roughness. The optimum deposition temperature is 250 °C in our tool and leads to rather smooth film surfaces, with roughness values of approximately 3 nm. The ALD Ru thin films have similar morphology compared with MS coatings, e.g., hexagonal polycrystalline structure and high density. Discrepancies of the optical properties can be explained by the higher roughness of ALD films compared to MS coatings. To use ALD Ru for optical applications at short wavelengths (λ = 2–50 nm), further improvement of their film quality is required.


2013 ◽  
Vol E96.C (3) ◽  
pp. 362-364
Author(s):  
Takeshi FUKUDA ◽  
Kenji TAKAGI ◽  
Norihiko KAMATA ◽  
Jungmyoung JU ◽  
Yutaka YAMAGATA

Nanomaterials ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1631
Author(s):  
Qiang Zhang ◽  
Yohanes Pramudya ◽  
Wolfgang Wenzel ◽  
Christof Wöll

Metal organic frameworks have emerged as an important new class of materials with many applications, such as sensing, gas separation, drug delivery. In many cases, their performance is limited by structural defects, including vacancies and domain boundaries. In the case of MOF thin films, surface roughness can also have a pronounced influence on MOF-based device properties. Presently, there is little systematic knowledge about optimal growth conditions with regard to optimal morphologies for specific applications. In this work, we simulate the layer-by-layer (LbL) growth of the HKUST-1 MOF as a function of temperature and reactant concentration using a coarse-grained model that permits detailed insights into the growth mechanism. This model helps to understand the morphological features of HKUST-1 grown under different conditions and can be used to predict and optimize the temperature for the purpose of controlling the crystal quality and yield. It was found that reactant concentration affects the mass deposition rate, while its effect on the crystallinity of the generated HKUST-1 film is less pronounced. In addition, the effect of temperature on the surface roughness of the film can be divided into three regimes. Temperatures in the range from 10 to 129 °C allow better control of surface roughness and film thickness, while film growth in the range of 129 to 182 °C is characterized by a lower mass deposition rate per cycle and rougher surfaces. Finally, for T larger than 182 °C, the film grows slower, but in a smooth fashion. Furthermore, the potential effect of temperature on the crystallinity of LbL-grown HKUST-1 was quantified. To obtain high crystallinity, the operating temperature should preferably not exceed 57 °C, with an optimum around 28 °C, which agrees with experimental observations.


Author(s):  
Antoine de Kergommeaux ◽  
Angela Fiore ◽  
Jérôme Faure-Vincent ◽  
Adam Pron ◽  
Peter Reiss
Keyword(s):  

Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 900
Author(s):  
Maria Vardaki ◽  
Aida Pantazi ◽  
Ioana Demetrescu ◽  
Marius Enachescu

In this work we present the results of a functional properties assessment via Atomic Force Microscopy (AFM)-based surface morphology, surface roughness, nano-scratch tests and adhesion force maps of TiZr-based nanotubular structures. The nanostructures have been electrochemically prepared in a glycerin + 15 vol.% H2O + 0.2 M NH4F electrolyte. The AFM topography images confirmed the successful preparation of the nanotubular coatings. The Root Mean Square (RMS) and average (Ra) roughness parameters increased after anodizing, while the mean adhesion force value decreased. The prepared nanocoatings exhibited a smaller mean scratch hardness value compared to the un-coated TiZr. However, the mean hardness (H) values of the coatings highlight their potential in having reliable mechanical resistances, which along with the significant increase of the surface roughness parameters, which could help in improving the osseointegration, and also with the important decrease of the mean adhesion force, which could lead to a reduction in bacterial adhesion, are providing the nanostructures with a great potential to be used as a better alternative for Ti implants in dentistry.


2016 ◽  
Vol 29 (6) ◽  
pp. 1483-1489 ◽  
Author(s):  
S. Aghabagheri ◽  
M. R. Mohammadizadeh ◽  
P. Kameli ◽  
H. Salamati

2019 ◽  
Vol 7 (36) ◽  
pp. 20733-20741 ◽  
Author(s):  
Mehri Ghasemi ◽  
Miaoqiang Lyu ◽  
Md Roknuzzaman ◽  
Jung-Ho Yun ◽  
Mengmeng Hao ◽  
...  

The phenethylammonium cation significantly promotes the formation of fully-covered thin-films of hybrid bismuth organohalides with low surface roughness and excellent stability.


1998 ◽  
Vol 545 ◽  
Author(s):  
J. C. Caylor ◽  
A. M. Stacy ◽  
T. Sands ◽  
R. Gronsky

AbstractBulk skutterudite phases based on the CoAs3 structure have yielded compositions with a high thermoelectric figure-of-merit (“ZT”) through the use of doping and substitutional alloying. It is postulated that further enhancements in ZT may be attained in artificially structured skutterudites by engineering the microstructure to enhance carrier mobility while suppressing the phonon component of the thermal conductivity. In this work the growth and properties of singlephase CoSb3 and IrSb3 skutterudite thin films are reported. The films are synthesized by pulsed laser deposition (PLD) where the crystallinity can be controlled by the deposition temperature. Powder X-ray diffraction (PXRD), Transmission electron microscopy (TEM) and Rutherford- Back Scattering (RBS) were used to probe phase, structure, morphology and stoichiometry of the films as functions of growth parameters and substrate type. A substrate temperature of 250°C was found to be optimal for the deposition of the skutterudites from stoichiometric targets. Above this temperature the film is depleted of antimony due to its high vapor pressure eventually reaching a composition where the skutterudite structure is no longer stable. However, when films are grown from antimony-rich targets the substrate temperature can be increased to at least 350°C while maintaining the skutterudite phase. In addition, adhesion properties of the films are explored in terms of the growth mode and substrate interaction. Finally, preliminary room temperature electrical and thermal measurements are reported.


2010 ◽  
Vol 518 (10) ◽  
pp. 2632-2636 ◽  
Author(s):  
Taslema Sultana ◽  
Golam Newaz ◽  
Grigor L. Georgiev ◽  
Ronald J. Baird ◽  
Gregory W. Auner ◽  
...  

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