scholarly journals Nanoimprinted multifunctional nanoprobes for a homogeneous immunoassay in a top-down fabrication approach

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hubert Brueckl ◽  
Astrit Shoshi ◽  
Stefan Schrittwieser ◽  
Barbara Schmid ◽  
Pia Schneeweiss ◽  
...  

AbstractMultifunctional nanoparticles are discussed as versatile probes for homogeneous immunoassays for in-vitro diagnostics. Top-down fabrication allows to combine and tailor magnetic and plasmonic anisotropic properties. The combination of nanoimprint lithography, thin film deposition, and lift-off processing provides a top-down fabrication platform, which is both flexible and reliable. Here, we discuss the material compositions and geometrical designs of monodisperse multicomponent nanoparticles and their consequences on optical and magnetic properties. The rotational hydrodynamics of nanoparticles is measured and considered under the influence of magnetic shape anisotropy in the framework of the Stoner-Wohlfarth theory. The plasmon-optical properties are explained by discrete-dipole finite-element simulations. Rotational dynamical measurements of imprinted nanoprobes for two test proteins demonstrate the applicability as highly sensitive biomolecular nanoprobes.

Coatings ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1124
Author(s):  
Chao Zhang ◽  
Markku Leskelä ◽  
Mikko Ritala

Patterning of thin films with lithography techniques for making semiconductor devices has been facing increasing difficulties with feature sizes shrinking to the sub-10 nm range, and alternatives have been actively sought from area-selective thin film deposition processes. Here, an entirely new method is introduced to self-aligned thin-film patterning: area-selective gas-phase etching of polymers. The etching reactions are selective to the materials underneath the polymers. Either O2 or H2 can be used as an etchant gas. After diffusing through the polymer film to the catalytic surfaces, the etchant gas molecules are dissociated into their respective atoms, which then readily react with the polymer, etching it away. On noncatalytic surfaces, the polymer film remains. For example, polyimide and poly(methyl methacrylate) (PMMA) were selectively oxidatively removed at 300 °C from Pt and Ru, while on SiO2 they stayed. CeO2 also showed a clear catalytic effect for the oxidative removal of PMMA. In H2, the most active surfaces catalysing the hydrogenolysis of PMMA were Cu and Ti. The area-selective etching of polyimide from Pt was followed by area-selective atomic layer deposition of iridium using the patterned polymer as a growth-inhibiting layer on SiO2, eventually resulting in dual side-by-side self-aligned formation of metal-on-metal and insulator (polymer)-on-insulator. This demonstrates that when innovatively combined with area-selective thin film deposition and, for example, lift-off patterning processes, self-aligned etching processes will open entirely new possibilities for the fabrication of the most advanced and challenging semiconductor devices.


Author(s):  
José Luis González-Vidal

Three sized Micropits were developed. Micropits were designed and fabricated using wet etching. MEMS fabrication consists of thin film deposition and patterned of several geometric structures. For Si substrate etching three layers SiO2/ Si3N4/ SiO2 were deposited and patterned. They were used as a mask. Micropit pattern was transferred by lift off technique. SiO2, Si3N4 layers and Si substrate were etched by HF, H3PO4 and KOH solutions. Si substrate has 7mm/h etching rate. Micropit micrographs were obtained by scanning electronic microscopy (SEM). Micropits are MEMS widely used in gas sensors, because they provide thermal isolation, Micropits will be used for gas microsensors, polisilicon microheater and gas sensor thin film will be deposited later. Today gas sensors have several applications in manufacturing & industry, such as, automotive, medicine/biomedical, consumer products, aerospace, chemical, optical displays, fluidics, wireless and optical communications.


Nanomaterials ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1860
Author(s):  
Jeonghun Yun ◽  
Yeongae Kim ◽  
Caitian Gao ◽  
Moobum Kim ◽  
Jae Yoon Lee ◽  
...  

The use of Prussian blue analogues (PBA) materials in electrochemical energy storage and harvesting has gained much interest, necessitating the further clarification of their electrochemical characteristics. However, there is no well-defined technique for manufacturing PBA-based microelectrochemical devices because the PBA film deposition method has not been well studied. In this study, we developed the following deposition method for growing copper hexacyanoferrate (CuHCFe) thin film: copper thin film is immersed into a potassium hexacyanoferrate solution, following which the redox reaction induces the spontaneous deposition of CuHCFe thin film on the copper thin film. The film grown via this method showed compatibility with conventional photolithography processes, and the micropattern of the CuHCFe thin film was successfully defined by a lift-off process. A microelectrochemical device based on the CuHCFe thin film was fabricated via micropatterning, and the sodium ion diffusivity in CuHCFe was measured. The presented thin film deposition method can deposit PBAs on any surface, including insulating substrates, and it can extend the utilization of PBA thin films to various applications.


Author(s):  
M. Grant Norton ◽  
C. Barry Carter

Pulsed-laser ablation has been widely used to produce high-quality thin films of YBa2Cu3O7-δ on a range of substrate materials. The nonequilibrium nature of the process allows congruent deposition of oxides with complex stoichiometrics. In the high power density regime produced by the UV excimer lasers the ablated species includes a mixture of neutral atoms, molecules and ions. All these species play an important role in thin-film deposition. However, changes in the deposition parameters have been shown to affect the microstructure of thin YBa2Cu3O7-δ films. The formation of metastable configurations is possible because at the low substrate temperatures used, only shortrange rearrangement on the substrate surface can occur. The parameters associated directly with the laser ablation process, those determining the nature of the process, e g. thermal or nonthermal volatilization, have been classified as ‘primary parameters'. Other parameters may also affect the microstructure of the thin film. In this paper, the effects of these ‘secondary parameters' on the microstructure of YBa2Cu3O7-δ films will be discussed. Examples of 'secondary parameters' include the substrate temperature and the oxygen partial pressure during deposition.


Author(s):  
E. L. Hall ◽  
A. Mogro-Campero ◽  
L. G. Turner ◽  
N. Lewis

There is great interest in the growth of thin superconducting films of YBa2Cu3Ox on silicon, since this is a necessary first step in the use of this superconductor in a variety of possible electronic applications including interconnects and hybrid semiconductor/superconductor devices. However, initial experiments in this area showed that drastic interdiffusion of Si into the superconductor occurred during annealing if the Y-Ba-Cu-O was deposited direcdy on Si or SiO2, and this interdiffusion destroyed the superconducting properties. This paper describes the results of the use of a zirconia buffer layer as a diffusion barrier in the growth of thin YBa2Cu3Ox films on Si. A more complete description of the growth and characterization of these films will be published elsewhere.Thin film deposition was carried out by sequential electron beam evaporation in vacuum onto clean or oxidized single crystal Si wafers. The first layer evaporated was 0.4 μm of zirconia.


2001 ◽  
Vol 11 (PR3) ◽  
pp. Pr3-553-Pr3-560 ◽  
Author(s):  
W. Zhuang ◽  
L. J. Charneski ◽  
D. R. Evans ◽  
S. T. Hsu ◽  
Z. Tang ◽  
...  

Author(s):  
Stephen R. Forrest

Organic electronics is a platform for very low cost and high performance optoelectronic and electronic devices that cover large areas, are lightweight, and can be both flexible and conformable to irregularly shaped surfaces such as foldable smart phones. Organics are at the core of the global organic light emitting device (OLED) display industry, and also having use in efficient lighting sources, solar cells, and thin film transistors useful in medical and a range of other sensing, memory and logic applications. This book introduces the theoretical foundations and practical realization of devices in organic electronics. It is a product of both one and two semester courses that have been taught over a period of more than two decades. The target audiences are students at all levels of graduate studies, highly motivated senior undergraduates, and practicing engineers and scientists. The book is divided into two sections. Part I, Foundations, lays down the fundamental principles of the field of organic electronics. It is assumed that the reader has an elementary knowledge of quantum mechanics, and electricity and magnetism. Background knowledge of organic chemistry is not required. Part II, Applications, focuses on organic electronic devices. It begins with a discussion of organic thin film deposition and patterning, followed by chapters on organic light emitters, detectors, and thin film transistors. The last chapter describes several devices and phenomena that are not covered in the previous chapters, since they lie outside of the current mainstream of the field, but are nevertheless important.


2020 ◽  
Vol 31 (9) ◽  
pp. 6948-6955
Author(s):  
Mustafa Özgür ◽  
Suat Pat ◽  
Reza Mohammadigharehbagh ◽  
Uğur Demirkol ◽  
Nihan Akkurt ◽  
...  

1990 ◽  
Author(s):  
J. Winter ◽  
F. Waelbroeck ◽  
P. Weinhold ◽  
H. G. Esser ◽  
J. von Seggern ◽  
...  

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