Surface roughness and electron backscattering in high aspect ratio silicon nanowires

High aspect ratio silicon nanowires (SiNWs) prepared by metal-assisted chemical etching were passivated by using catalytic chemical vapor deposition (Cat-CVD).

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Wafer-Scale, Highly-Ordered Silicon Nanowires Produced by Step-and-Flash Imprint Lithography and Metal-Assisted Chemical Etching

MRS Proceedings ◽

10.1557/opl.2012.1663 ◽

2012 ◽

Vol 1512 ◽

Author(s):

Jian-Wei Ho ◽

Qixun Wee ◽

Jarrett Dumond ◽

Li Zhang ◽

Keyan Zang ◽

...

Keyword(s):

Aspect Ratio ◽

Cross Sections ◽

Silicon Nanowires ◽

High Aspect Ratio ◽

Chemical Etching ◽

Semiconductor Device ◽

Imprint Lithography ◽

Wafer Level ◽

Conventional Photolithography ◽

Metal Assisted Chemical Etching

ABSTRACTA combinatory approach of Step-and-Flash Imprint Lithography (SFIL) and Metal-Assisted Chemical Etching (MacEtch) was used to generate near perfectly-ordered, high aspect ratio silicon nanowires (SiNWs) on 4" silicon wafers. The ordering and shapes of SiNWs depends only on the SFIL nanoimprinting mould used, thereby enabling arbitary SiNW patterns not possible with nanosphere and interference lithography (IL) to be generated. Very densely packed SiNWs with periodicity finer than that permitted by conventional photolithography can be produced. The height of SiNWs is, in turn, controlled by the etching duration. However, it was found that very high aspect ratio SiNWs tend to be bent during processing. Hexagonal arrays of SiNW with circular and hexagonal cross-sections of dimensions 200nm and less were produced using pillar and pore patterned SFIL moulds. In summary, this approach allows highlyordered SiNWs to be fabricated on a wafer-level basis suitable for semiconductor device manufacturing.

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Dropwise Condensation on High Aspect-Ratio Surface Roughness

Volume 1: Heat Transfer in Energy Systems; Theory and Fundamental Research; Aerospace Heat Transfer; Gas Turbine Heat Transfer; Transport Phenomena in Materials Processing and Manufacturing; Heat and ◽

10.1115/ht2012-58080 ◽

2012 ◽

Cited By ~ 1

Author(s):

Qingjun Cai ◽

Chialun Tsai

Keyword(s):

Surface Roughness ◽

Aspect Ratio ◽

High Aspect Ratio ◽

Dropwise Condensation

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Nanostructured Electrodes for Improved Neural Recording

MRS Proceedings ◽

10.1557/proc-729-u4.11 ◽

2002 ◽

Vol 729 ◽

Cited By ~ 4

Author(s):

Karen C. Cheung ◽

Yang-Kyu Choi ◽

Tim Kubow ◽

Luke P. Lee

Keyword(s):

Cell Culture ◽

Surface Roughness ◽

Aspect Ratio ◽

High Aspect Ratio ◽

Electrode Surface ◽

Neural Recording ◽

New Method ◽

Nanostructured Electrodes

AbstractWe present a new method of increasing the effective electrode surface for improved neural recording. To optimize the electrode, the impedance can be decreased by introducing surface roughness or nanostructures on the electrode. High aspect ratio pillar-like polysilicon nanostructures are created in a reactive ion etch. Nanostructure robustness in cell culture is examined.

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Parameter Optimization for Grinding Process of Micropores with High Aspect Ratio

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1095.795 ◽

2015 ◽

Vol 1095 ◽

pp. 795-799

Author(s):

Feng Che Tsai ◽

Yann Long Lee ◽

Ju Chun Yeh

Keyword(s):

Surface Roughness ◽

Aspect Ratio ◽

Parameter Optimization ◽

High Aspect Ratio ◽

Grinding Process ◽

Average Roughness ◽

Abrasive Particles ◽

Abrasive Jet Machining ◽

Mix Proportion ◽

Labor Consuming

Parameter optimization for grinding process of micropores with high aspect ratio is discussed in this research. To ensure the surface accuracy on the inner side of deep micropore, the manual polishing or reaming process is a commonly adopted method. However, this process has disadvantages of limitation by operators’ experience and technique, labor consuming, and high cost. Skilled operators are also difficult to train nowadays. In order to address those flaws, this study applied the subtle abrasive jet machining technology and Taguchi Method for experimental design, so as to effectively obtain the appropriate surface roughness and processing uniformity. The Taguchi experimental results showed that when applying a Vacuum Pressure of 60 cmHg and a Air Pressure of 0.5 Mpa, the optimal polishing effect was attained using #2000SiC abrasive particles and an Mix Proportion (SiC: Additive) 2: 1. The average roughness of lifting pin hole was reduced from an original value of Ra 2.39 mm (Rmax: 10.74 mm) to a final value of Ra 0.07 mm (Rmax: 1.10 mm).

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