• Journal of the Korean Society for Precision Engineering
• /
• v.28 no.2
• /
• pp.245-250
• /
• 2011

A high-resolution shadow mask, a nanostencil, is widely used for high resolution lithography. This high-resolution shadowmask is often fabricated by a combination of MEMS processes and focused ion beam (FIB) milling. In this study, FIB milling on 500-nm-thin SiN membrane was tested and characterized. 500 nm thick and $2{\times}2$ mm large membranes were made on a silicon wafer by micro-fabrication processes of LPCVD, photolithography, ICP etching and bulk silicon etching. A subsequent FIB milling enabled local membrane thinning and aperture making into the thinned silicon nitride membrane. Due to the high resolution of the FIB milling process, nanoscale apertures down to 60 nm could be made into the membrane. The nanostencil could be used for nanoscale patterning by local deposition through the apertures.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2005.10a
• /
• pp.322-325
• /
• 2005

The shrinking critical dimensions of modern technology place a heavy requirement on optimizing feature shapes at the micro- and nano scale. In addition, the use of ion beams in the nano-scale world is greatly increased by technology development. Especially, Focused ion Beam (FIB) has a great potential to fabricate the device in nano-scale. Nevertheless, FIB has several limitations, surface swelling in low ion dose regime, precipitation of incident ions, and the re-deposition effect due to the sputtered atoms. In recent years, many approaches and research results show that the re-deposition effect is the most outstanding effect to overcome or reduce in fabrication of micro and nano devices. A 2D string based simulation software AMADEUS-2D $(\underline{A}dvanced\;\underline{M}odeling\;and\;\underline{D}esign\;\underline{E}nvironment\;for\;\underline{S}putter\;Processes)$ for ion milling and FIB direct fabrication has been developed. It is capable of simulating ion beam sputtering and re-deposition. In this paper, the 2D FIB simulation is demonstrated and the characteristics of ion beam induced direct fabrication is analyzed according to various parameters. Several examples, single pixel, multi scan box region, and re-deposited sidewall formation, are given.

• 전자공학회논문지 IE
• /
• v.47 no.2
• /
• pp.8-12
• /
• 2010

TEM is a powerful tool for semiconductor material analyses in structure or biological sample in micro structure. TEM observation need to make to coincide specimens for special purpose. in this paper, we have experimented for minimum surface damage on bulk wafer and patterned specimen by various conditions such as accelerating energy, depth of ion beam, ion milling types, and etc. in various specimen preparation methods by FIB (Focus Ion Beam). The optimal qualified specimens are contain low mounts of surface damage(about 5 nm) on patterned specimen.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2008.06a
• /
• pp.109-110
• /
• 2008

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2006.05a
• /
• pp.489-490
• /
• 2006

To establish fabrication techniques for nano structure understanding of focused ion beam (FIB) milling process is required. In this study the mathematical model containing the factors related to FIB milling is developed to acquire the optimal fabrication condition. Then, the model is verified by comparison with various nano pattern fabricated in actual FIB system. Consequently, it is demonstrated that the nano patterns with the smallest pitch can be fabricated using developed FIB milling model.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2005.06a
• /
• pp.1194-1197
• /
• 2005

Micro nozzle is employed as a dynamic passive valve in micro fluidic devices. Micro nozzle array is used in micro droplet generation in bio-medical applications and propulsion device for actuating satellite and aerospace ship in vacuum environments. Aperture angle and the channel length of the micro nozzle affect its retification efficiency, and thus it is needed to produce micro nozzle precisely. MEMS process has a limit on making a micro nozzle with high-aspect ratio. Reactive ion etching process can make high-aspect ratio structure, but it is difficult to make the complex shape. Focused ion beam deposition has advantage in machining of three-dimensional complex structures of sub-micron size. Moreover, it is possible to monitor machining process and to correct defected part at simultaneously. In this study, focused ion beam deposition was applied to micro nozzle production.

• Journal of the Korean Society for Precision Engineering
• /
• v.23 no.3 s.180
• /
• pp.56-60
• /
• 2006

A high-resolution shadow mask, or called a nanostencil was fabricated for high resolution lithography. This high-resolution shadowmask was fabricated by a combination or MEMS processes and focused ion beam (FIB) milling. 500 nm thick and $2{\times}2mm$ large membranes wore made on a silicon wafer by micro-fabrication processes of LPCVD, photolithography, ICP etching and bulk silicon etching. A subsequent FIB milling enabled local membrane thinning and aperture making into the thinned silicon nitride membrane. Due to the high resolution of the FIB milling process, nanoscale apertures down to 70 nm could be made into the membrane. By local deposition through the apertures of nanostencil, nanoscale patterns down to 70 nm could be achieved.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2004.10a
• /
• pp.871-874
• /
• 2004

Fabrication of a high-resolution shadow mask, or called nanostencil, is presented. This high-resolution shadowmask is fabricated by a combination of MEMS processes and focused ion beam (FIB) milling. 500 nm thick and 2x2 mm large membranes are made on a silicon wafer by micro-fabrication processes of LPCVD, photolithography, ICP etching and bulk silicon etching. Subsequent FIB milling enabled local membrane thinning and aperture making into the thinned silicon nitride membrane. Due to high resolution of FIB milling process, nanoscale apertures down to 70 nm could be made into the membrane.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2005.10a
• /
• pp.318-321
• /
• 2005

FIB (Focused ion Beam) milling on a 500-nm-thick silicon nitride membrane was studied in order to fabricate a high-resolution shadow mask, or called a nanostencil. The silicon nitride membrane was fabricated by MEMS processes of LPCVD, photolithography, ICP etching and bulk silicon etching. The apertures made by FIB milling and normal photolithography were compared. The square metal pattern deposited through FIB milled shadow mask showed 6 times smaller comer radius than the case of photolithography. The results show high resolution patterning could be achieved by local deposition through FIB milled shadow-mask.

• Applied Microscopy
• /
• v.40 no.4
• /
• pp.177-183
• /
• 2010

A focused ion beam (FIB) system produces a beam of positive ions (usually gallium) which are heavier than electrons and can be focused by electrostatic lenses into a spot on the specimen. With its ability milling of the specimen material by 10 to 100 nm with each pass of the beam, FIB is widely adopted in materials science, semiconductor industry, and ceramics research. Recently, FIB has been increasingly employed in the field of biomedical sciences. Here we provide a brief introduction to FIB and its applications for a wide variety of biomedical research. The surface of specimen can be in situ processed and quasi-real time visualized by two beam combination of FIB and field emission scanning electron microscope (FESEM). Due to its milling process, internal structures can be exposed and analyzed: yeast cells, fungus-inoculated wheat leaf, mannitol particles in inhalation aerosols, and oyster shell. Serial blockface tomography with the system kindles 3-dimensional reconstruction researches in the realm of nervous system and life sciences. Two-beam system of FIB/FESEM is a versatile tool to be utilized in the biomedical sciences, especially in 3-dimensional reconstruction studies.