Three-Dimensional ES Barrier Promotes the Steps Formation

2018 ◽  
Vol 783 ◽  
pp. 115-119
Author(s):  
Jin Yang ◽  
Ya Jun Zhou ◽  
Bing Xue Pu

Physical vapor deposition (PVD) has been an important method to synthesize metallic nanorods during the past two decades. Based on the main physical process of crystal growth, this letter made a growth model of metallic nanorods with kinetic lattice Monte Carlo (KLMC) method and studied the effects of three-dimensional (3D) Ehrlich–Schwoebel (ES) barrier during the metallic nanorods growth. According to the simulation results, a large 3D ES barrier affects the surface morphology apparently. With analyze the simulation results, 3D ES barrier promotes the step formation and increases the step height greatly, and it is the main factor of metallic nanorods formation.

2013 ◽  
Vol 110 (13) ◽  
Author(s):  
Xiaobin Niu ◽  
Stephen P. Stagon ◽  
Hanchen Huang ◽  
J. Kevin Baldwin ◽  
Amit Misra

2005 ◽  
Author(s):  
Umesh Kelkar ◽  
Arvind Sundarrajan ◽  
Tza-Jing Gung ◽  
Ned Hammond ◽  
Ajay Bhatnagar ◽  
...  

A new physical vapor deposition source is developed to meet the challenges of barrier deposition for sub 100nm devices. The source employs multi-step process to deposit thin, conformal and uniform barrier films. This paper describes reactor scale modeling and simulation of deposition and etching plasmas used for barrier deposition. The modeling and simulation in tandem with experimental data demonstrate that the chamber can be used to independently control the particle fluxes as per the requirements of the deposition and etching steps. The simulation results were qualitatively used to optimize the ion flux uniformity by altering the magnetic fields near the wafer.


2019 ◽  
Vol 33 (31) ◽  
pp. 1950371
Author(s):  
Tianlong Liu ◽  
Shiliang Wang ◽  
Lizhen Hou ◽  
Han Huang

Pentagonal noble metal crystals, with a five-fold-twinned (FFT) structure that exhibits prominent noncrystallographic symmetry, have been the focus of research in the past several decades due to their promising applications in various fields such as chemical and biological sensors, electronics and optoelectronics. A great deal of previous experimental studies and theoretical analyses suggested that such an FFT structure could only exist in the nanoscale crystals, because of the lateral restriction in growth, or in microscale crystals with re-entrant grooves that can effectively release the internal strain. In this study, we synthesized the microscale single-crystalline and multi-twinned Ag crystals with various morphologies, using physical vapor deposition (PVD). FFT Ag microwhiskers with diameters up to 10 [Formula: see text]m were produced, but without re-entrant grooves on their side surfaces. Our findings suggest that FFT whiskers can be formed without the use of any surface-capping agents or without necessitating restriction in lateral growth. This further suggests that the current understanding of the surface passivation or the strain-restriction formation of five-fold-twined micro- and nanowhiskers needs improvement.


2016 ◽  
Vol 6 (1) ◽  
pp. 17-22 ◽  
Author(s):  
Zhuoxian Wang ◽  
Paul R. West ◽  
Xiangeng Meng ◽  
Nathaniel Kinsey ◽  
Vladimir M. Shalaev ◽  
...  

Abstract


Author(s):  
B. Li ◽  
P. A. Clark ◽  
K. H. Church

The development of functional and reliable miniaturized devices including Micro Electro Mechanical Systems (MEMS) has stressed the manufacturing and packaging processes. The traditional micro fabrication techniques, such as lithography, physical vapor deposition (PVD), chemical vapor deposition (CVD) and etching, are layer-by-layer processes and mostly suitable for thin-filmed devices. LIGA (an acronym from German words for lithography, electroplating, and molding) is a newly developed process for thick metallic devices; however, it involves electroplating process and high quality molds, which are hard to move after electroforming. In all the processes mentioned above, masks and photoresist processing are inevitable, which complicates the whole process and increases the processing time and the total cost. It is also well known that packaging is another barrier for the advancement of MEMS. MEMS packaging, which is required to provide mechanical support, environmental protection and electrical connection to other system components, is much more complicated as compared to electronic components due to the moving structures, fluids or chemicals involved. It is the most expensive process in micromachining. Therefore, enabling tools and technologies are greatly needed for the fabrication and packaging of complicated devices and highly integrated micro assemblies. In this paper, we will present novel direct-print dispensing techniques and robust tools for 21st century manufacturing and packaging. Comparing to other dispensing technologies such as time-pressure needle dispensing, screen printing, pin transfer and jetting, nScrypt’s pumping techniques can dispense materials with precise volume control for 10’s of Pico liter resolution, accurate placement or alignment within a few microns, conformably print on exaggerated surfaces of 10’s of centimeters, and are extremely flexible with materials and patterns. The dispensing tip (nozzle) is optimized to reduce the pressure drop as compared to the traditional tubing needles. Comparing to traditional micro fabrication technologies, our direct-print dispensing technology is maskless and thus a cost effective process. While micro-dispensing is a solution based approach, it has the advantage of not being a wet process such as wet etching or electroplating. Direct-print dispensing of micro lines, micro dots, and three-dimensional structures will be presented. The technology has a wide range of applications in the manufacturing and packaging of micro/meso-scale devices and bio structures.


2018 ◽  
Vol 140 (5) ◽  
Author(s):  
Arnaud Duchosal ◽  
Damien Joly ◽  
René Leroy ◽  
Roger Serra

In this paper, the effect of compacted graphite iron (CGI) microstructure has been investigated in tribological strategy. From industrial context, two coatings have been chosen: a single layer coating (physical vapor deposition (PVD)) and a multilayer coating (chemical vapor deposition (CVD)). Pin-on-disk tests have been done to analyze wear mechanisms and to directly obtain the coefficient of friction. Rotation speed of the disk has been adjusted to get the same linear velocity on different disk radii to get up to 150 m min−1 similar to machining condition. Three-dimensional (3D) profilometer, scanning electron microscopy, and nano-indentation were used to observe the track profiles, the pin, and the disk wears and to measure the hardness of microstructure components, respectively. Results showed that PVD coating was more abrasive and had more volume of sticking materials. Chemical vapor deposition coating, which could be the most appropriate for machining CGI, has a real antisticking property and has less friction coefficient than PVD coating. But the presence of small TiCN precipitates in CGI material has a proven negative effect in CVD coating lifetime.


2013 ◽  
Vol 2 (3) ◽  
pp. 259-267 ◽  
Author(s):  
Stephen P. Stagon ◽  
Hanchen Huang

AbstractMetallic nanorods have a wide range of important technological applications. Fabrication of metallic nanorods of ~100 nm using physical vapor deposition (PVD) has been commonplace for several decades. On this length scale, nanorods have similar functionalities to bulk thin films with the advantage of increased surface area. When the lateral dimension is decreased to ~10 nm new functionalities emerge that are not present in thin film counterparts, such as catalysis. Small metallic nanorods, those ~10 nm, have classically been made through solution-based synthesis. Alternatively, recent advances in scientific understanding, a framework of nanorod growth, have opened the door to the fabrication of small nanorods through PVD. Growing small nanorods through PVD offers technologically relevant advantages over solution-based processing like direct control of aspect ratio, pure high-vacuum processing, and oriented attachment to a substrate. Among materials, gold (Au) has a wide range of technological applications and is a good prototype for understanding the behavior of common face center cubic metals. This article reviews solution processing and PVD of small metallic nanorods using Au as a prototype, in terms of scientific understanding and fabrication knowledge, and further compares and contrasts the two approaches.


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