• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2013.05a
• /
• pp.615-616
• /
• 2013

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2013.05a
• /
• pp.633-634
• /
• 2013

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2010.05a
• /
• pp.679-680
• /
• 2010

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.33 no.3
• /
• pp.224-230
• /
• 2009

FIB has been commonly used as a very powerful tool in the semiconductor industry. It is mainly used for mask repair, device correction, failure analysis and IC error correction, etc. Currently, FIB is not being applied to the fabrication of the micro and nano-structured mold, because of low productivity. And also sputtering rate has been required to fabricate 3D shape. In the paper, we studied the FIB-Sputtering rate according to mold materials. And surface roughness characteristics had been analysed for micro or nano mold fabrication. Si wafer, Glassy Carbon, STAVAX and DLC that have been normally considered as good micro or nano mold materials were used in the study.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.38 no.8
• /
• pp.875-880
• /
• 2014

Recently, three-dimensional scaffolds and nanofibers are being developed for bone tissue regeneration. In this study, we fabricated a hybrid scaffold using a nano-micro precision deposition system. The fabrication process involved the application of the solid freeform fabrication (SFF) technology and electrospinning. The hybrid scaffolds were combined using micro scaffolds and nanofibers. The nanofibers were deposited on each layer of the micro scaffolding using the electrospinning process. The micro scaffolds were fabricated using the SFF technology at a temperature of $100^{\circ}C$, pressure of 650 kPa, and scan velocity of 250 mm/s. Nanofiber fabrication was conducted by means of electrospinning using the flow rate, solution concentration, distance from the tip to the collector (TCD), and voltage. The nanofibers were fabricated using a flow rate of 0.1 ml/min, voltage of 5 kV, TCD of 1 mm, and 10 wt% of solution concentration. MG-63 cells were seeded into the hybrid scaffold for the purpose of its evaluation.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.5 no.2
• /
• pp.186-190
• /
• 2004

By this time, a mold with nano size pattern was produced using a fabrication of X-ray lithography method and in a m icro size's case it was produced using fabrication of Deep UV lithography. In this paper, we produced mold with 400 $\mu{m}$depth pattern using a new technology of SLS(Selective Laser Sintering) Rapid Prototyping method. In addition to enhance strength and thermal stability, we produced Ni structure with a thickness of 300 $\mu{m}$ on a surface of mold using electro forming method.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2008.06a
• /
• pp.125-126
• /
• 2008

• Composites Research
• /
• v.20 no.5
• /
• pp.49-55
• /
• 2007

Nanocomposite blade for dicing semiconductor wafer is investigated for micro/nano-device and micro/nano-fabrication. While metal blade has been used for dicing of silicon wafer, polymer composite blades are used for machining of quartz wafer in semiconductor and cellular phone industry in these days. Organic-inorganic material selection is important to provide the blade with machinability, electrical conductivity, strength, ductility and wear resistance. Maintaining constant thickness with micro-dimension during shaping is one of the important technologies fer machining micro/nano fabrication. In this study the fabrication of blade by wet processing of mixing conducting nano ceramic powder, abrasive powder phenol resin and polyimide has been investigated using an experimental approach in which the thickness differential as the primary design criterion. The effect of drying conduction and post pressure are investigated. As a result wet processing techniques reveal that reliable results are achievable with improved dimension tolerance.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
• /
• 2002.05a
• /
• pp.40-44
• /
• 2002

The motivation of this work is to use SAM(Self-Assembled Monolayer) for developing a rapid and flexible non-photolithographic nano-structure fabrication technique which can be utilized in micro-machining of metals as well as silicon-based materials. The fabrication technique implemented in this work consists of a two-step process, namely, mechanical scribing followed by chemical etching. From the experimental results, it was found that thiol on copper surface could be removed even under a few nN normal load. The nano-tribological characteristics of thiol-SAM on various metals were largely dependent on the native oxide layer of metals. Based on these findings, nano-patterns with sub-micrometer width and depth on metal surfaces such as Cu, Au and Ag could be obtained using a diamond-coated tip.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.29 no.7 s.238
• /
• pp.998-1004
• /
• 2005

A nano-stereolithography (NSL) process has been developed for fabrication of 3D shell structures which can be applied to various nano/micro-fluidic devices. By the process, a complicated 3D shell structure on a scale of several microns can be fabricated using lamination of layers with a resolution of 150 nm in size, so it does not require the use of my sacrificial layer or any supporting structure. A layer was fabricated by means of solidifying liquid-state monomers using two-photon absorption (TPA) induced using a femtosecond laser processing. When the polymerization process is finished, unsolidified liquid state resins can be removed easily by dropping several droplets of ethanol fur developing the fabricated structure. Through this work, some 3D shell structures, which can be applied to various applications such as nano/micro-fluidic devices and MEMS system, were fabricated using the developed process.