Physical Self-Assembly And Nano-Patterning

AbstractIt is known that oblique angle deposition (or glancing angle deposition) can create 3D architectures that are otherwise difficult to produce using the conventional lithographic techniques. The technique relies on a self-assembly mechanism originated from a physical shadowing effect during deposition. In this paper we show examples of 3D nanostructures obtained by this oblique angle deposition on a templated substrate with regularly spaced pillar seeds. We show that common to this technique is the phenomenon of side-way growth on the seeds. The side-way growth leads to a fan-like structure at the initial stages of growth if the incident oblique angle is fixed during growth. Simulations based on a steering effect due to the attractive force between the incoming atom and the existing atoms on the surface produce a fanlike structure similar to that observed experimentally. We show that a two-phase substrate rotation scheme during deposition can dramatically reduce this fan-out effect and can lead to uniform and isolated columns.

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Structural Evolution of Nanostructured YBa2Cu3Ox Thin Films Formed by Pulsed Laser Glancing Angle Deposition

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.121-123.947 ◽

2007 ◽

Vol 121-123 ◽

pp. 947-950

Author(s):

H.H. Wang ◽

Y.P. Zhao

Keyword(s):

Thin Films ◽

Laser Fluence ◽

Pulsed Laser ◽

Structural Evolution ◽

Glancing Angle Deposition ◽

Ambient Oxygen ◽

Glancing Angle ◽

Shadowing Effect ◽

Ambient Gas ◽

Angle Deposition

Nano-structured thin films of amorphous YBa2Cu3Ox were prepared by pulsed laser glancing angle deposition. Ambient oxygen pressure and laser fluence have a strong effect on the microstructure of the films. The films exhibit a structural evolution from isolated nanorods, through network of vertical nanocolumns, to nanoparticles fractal with increasing ambient oxygen pressures. Shadowing effect, surface diffusion and flux scattering by ambient gas play main roles in determining the structural evolution.

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Hydrophobic Metallic Nanorods coated with Teflon Nanopatches by Glancing Angle Deposition

MRS Proceedings ◽

10.1557/proc-1188-ll09-03 ◽

2009 ◽

Vol 1188 ◽

Author(s):

Wisam J Khudhayer ◽

Rajesh Sharma ◽

Tansel Karabacak

Keyword(s):

Contact Angle ◽

Normal Incidence ◽

Glancing Angle Deposition ◽

Nanorod Arrays ◽

Hydrophobic Property ◽

Glancing Angle ◽

Shadowing Effect ◽

Glad Technique ◽

Metallic Nanorods ◽

Angle Deposition

AbstractIntroducing a hydrophobic property to vertically aligned hydrophilic metallic nanorods was investigated experimentally and theoretically. First, platinum nanorod arrays were deposited on flat silicon substrates using a sputter Glancing Angle Deposition Technique (GLAD). Then a thin layer of Teflon (nanopatches) was partially deposited on the tips of platinum nanorod at a glancing angle of  = 85° as well as at normal incidence ( = 0°) for different deposition times. We show that GLAD technique is capable of depositing ultrathin isolated Teflon nanopatches on selective regions of nanorod arrays due to the shadowing effect during GLAD. Contact angle measurements on Pt/Teflon nano-composite have shown contact angle values as high as 138°, indicating a significant increase in the hydrophobicity of originally hydrophilic Pt nanostructures. Finally, a 2D simplified wetting model utilizing Cassie and Baxter theory of heterogeneous surfaces has been developed to explain the wetting behavior of Pt/Teflon nanocomposite.

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Improved Microstructures for Thermal Barrier Coatings Produced by Glancing Angle Deposition

MRS Proceedings ◽

10.1557/proc-555-97 ◽

1998 ◽

Vol 555 ◽

Cited By ~ 1

Author(s):

K. D. Harris ◽

D. Vick ◽

M. J. Brett ◽

K. Robbie

Keyword(s):

Thin Films ◽

Electron Beam Evaporation ◽

Glancing Angle Deposition ◽

Thermal Barrier ◽

Porous Films ◽

New Approach ◽

Barrier Coating ◽

Glancing Angle ◽

Shadowing Effect ◽

Angle Deposition

AbstractA new approach to deposition of thin films for thermal barrier applications is described. During electron beam evaporation, the extreme shadowing effect that is present at highly oblique incidence is employed to introduce porosity into thin films of zirconia. Using controlled substrate motion a solid capping layer may be applied to these porous films. By depositing layers of porous material and capping in an alternating fashion a new structure is produced which warrants evaluation as an improved thermal barrier coating.

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Evolution of Crystal Orientation in Obliquely Deposited Magnesium Nanostructures for Hydrogen Storage Applications

MRS Proceedings ◽

10.1557/proc-1042-s04-06 ◽

2007 ◽

Vol 1042 ◽

Cited By ~ 2

Author(s):

Mehmet F. Cansizoglu ◽

Fumiya Watanabe ◽

Pei-I Wang ◽

Tansel Karabacak

Keyword(s):

Thin Films ◽

Self Assembly ◽

Crystal Orientation ◽

Oblique Angle Deposition ◽

X Ray Diffraction ◽

Crystal Orientations ◽

Electron Microscopy Analysis ◽

Shadowing Effect ◽

Microscopy Analysis ◽

Angle Deposition

AbstractCrystal orientation (texture) is an important parameter in the hydrogen absorption and desorption properties of various materials. In this study, we investigate the formation of magnesium nanorod arrays with crystal orientations that are not normally observed in conventional Mg thin films. Mg nanorods are produced using an oblique angle deposition technique through a physical self-assembly process. In this study sputtering and thermal evaporation systems are utilized for the growth of Mg nanorods and thin films on silicon wafer pieces. We present a detailed X-ray diffraction and scanning electron microscopy analysis. It is discussed that under oblique incidence, evolution of crystal orientations with lower adatom mobility are promoted due to the shadowing effect.

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Physical self-assembly and the nucleation of three-dimensional nanostructures by oblique angle deposition

Journal of Vacuum Science & Technology A Vacuum Surfaces and Films ◽

10.1116/1.1743178 ◽

2004 ◽

Vol 22 (4) ◽

pp. 1778-1784 ◽

Cited By ~ 100

Author(s):

T. Karabacak ◽

G.-C. Wang ◽

T.-M. Lu

Keyword(s):

Self Assembly ◽

Three Dimensional ◽

Oblique Angle Deposition ◽

Oblique Angle ◽

Angle Deposition

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Fabrication of Nanochannels Using Glancing Angle Deposition With Line Seeds

Volume 2: Manufacturing Processes; Manufacturing Systems; Nano/Micro/Meso Manufacturing; Quality and Reliability ◽

10.1115/msec2020-8450 ◽

2020 ◽

Author(s):

Chuang Qu ◽

Dilan Ratnayake ◽

Bruce Alphenaar ◽

Shamus McNamara ◽

Kevin Walsh

Keyword(s):

Cross Sections ◽

Physical Vapor Deposition ◽

Flexible Substrate ◽

Glancing Angle Deposition ◽

Cross Sectional ◽

Sensing Applications ◽

Glancing Angle ◽

Shadowing Effect ◽

Nanofabrication Technique ◽

Angle Deposition

Abstract This paper presents the fabrication of nanochannels using glancing angle deposition (GLAD) with line seeds. GLAD is a bottom-up nanofabrication technique that creates nanometer-level features by the ballistic shadowing effect at oblique incident angles in physical vapor deposition (PVD) processes. GLAD exhibits the unique advantage to create 3D nanofeatures such as nanocolumns, helices, chevrons, and combinations, comparing to top-down nanonamufacturing techniques. Advanced seeding schemes allow GLAD to produce ordered nanostructure arrays. In this paper, we focus on studying the design rules of line seeds for GLAD, and the potential for creating nanochannels using GLAD nanoribbons grown from the line seeds. Unlike traditional one-dimensional (1D) point seeds, the cross-sectional profiles of line seeds have an important impact on the size and morphology of the nanoribbons. We demonstrated that line seeds with circular cross-sections and micrometer widths created from conventional photolithography can be used for creating ribbons with width less than 300 nm. The centimeter-long nanoribbons are used as nanotemplates for nanochannels. The process is compatible with various materials such as parylene C and silicon dioxide as the capping material, and rigid/flexible substrate choices for the nanochannels as well. The nanochannels created by GLAD with line seeds can potentially be used in nanofluidics, biological, and sensing applications.

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Response of MG63 osteoblast-like cells to ordered nanotopographies fabricated using colloidal self-assembly and glancing angle deposition

Biointerphases ◽

10.1116/1.4931889 ◽

2015 ◽

Vol 10 (4) ◽

pp. 04A306 ◽

Cited By ~ 13

Author(s):

Peng-Yuan Wang ◽

Dines T. Bennetsen ◽

Morten Foss ◽

Helmut Thissen ◽

Peter Kingshott

Keyword(s):

Self Assembly ◽

Glancing Angle Deposition ◽

Glancing Angle ◽

Angle Deposition

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Fabrication of a Large-Area Superhydrophobic SiO2 Nanorod Structured Surface Using Glancing Angle Deposition

Journal of Nanomaterials ◽

10.1155/2017/8305439 ◽

2017 ◽

Vol 2017 ◽

pp. 1-7 ◽

Cited By ~ 2

Author(s):

Xun Lu ◽

Seok-min Kim ◽

Seong Jun Seo

Keyword(s):

Rotation Speed ◽

Processing Condition ◽

Contact Angles ◽

Glancing Angle Deposition ◽

Dominant Factor ◽

Oblique Angle ◽

Functional Nanostructures ◽

Glancing Angle ◽

Deposition Thickness ◽

Angle Deposition

A glancing angle deposition (GLAD) technique was used to generate SiO2 nanorods on a glass substrate to fabricate a low-cost superhydrophobic functional nanostructured surface. GLAD-deposited SiO2 nanorod structures were fabricated using various deposition rates, substrate rotating speeds, oblique angles, and deposition times to analyze the effects of processing conditions on the characteristics of the fabricated functional nanostructures. The wettability of the surface was measured after surface modification with a self-assembled monolayer (SAM). The measured water contact angles were primarily affected by substrate rotation speed and oblique angle because the surface fraction of the GLAD nanostructure was mainly affected by these parameters. A maximum contact angle of 157° was obtained from the GLAD sample fabricated at a rotation speed of 5 rpm and an oblique angle of 87°. Although the deposition thickness (height of the nanorods) was not a dominant factor for determining the wettability, we selected a deposition thickness of 260 nm as the optimum processing condition based on the measured optical transmittance of the samples because optically transparent films can serve as superhydrophobic functional nanostructures for optical applications.

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