∗1University of Phayao19 Moo. 2, T. Maeka, A. Muang, Phayao 56000, Thailand
∗2Hanoi University of Science and Technology, Hanoi, Vietnam∗3Okayama University of Science, Okayama, Japan
∗4Tokyo Institute of Technology, Tokyo, Japan†Corresponding author, E-mail: [email protected]
[Received July 29, 2019; accepted November 6, 2019]
In this paper, a chemical lift-off process using ace-tone ink was examined to attain the easy fabricationof metallic nano/microstructures. This process con-sists of five steps: cleaning of the substrate, chemicalstamping, metal film deposition, coating with glue, andselective peeling. Details of the hot embossing processfor the cycloolefin polymer (COP) film mold fabrica-tion and the selection of the organic solvent ink for thechemical stamping are also explained. The fabricationof several kinds of metallic nano/microstructures, suchas Au line and space structures, Au square film arrays,and Au dot arrays, is demonstrated. It is shown thatmetal films coated on the stamped region peeled offwith the glue, and a metal film shaped in the stamp’snegative pattern remained on the substrate. Acetoneis effective for reducing the surface energy of the sub-strate and the bonding strength, resulting in selectivepeeling of the coated metal film.
Keywords: stamping, Au coating, plastic mold, acetone
1. Introduction
Metallic nanostructures have great potential to be uti-lized in various applications, such as bio-molecular sen-sors [1, 2], nanoelectronic devices [3, 4], display de-vices [5], and catalysts [6, 7]. For example, metallicnanoparticles exhibit unique optical characteristics at-tributed to localized surface plasmon resonance (LSPR),which is due to the collective oscillations of electrons in-duced by the electromagnetic field of the incident light.The LSPR characteristics are evaluated by the absorbancespectrum, where a sharp peak is observed at the wave-length of the resonance frequency. The peak wavelengthof the absorbance spectrum is mainly dependent on thesize, shape, and alignment of the nanoparticles [8–11].Interestingly, the LSPR resonance frequency is also de-pendent on the refractive index of the surrounding en-
vironmental medium. This property is expected to beuseful in biosensors. Other metallic nanostructures, suchas nano-lines [12], nanowires [13–16], nanodots [17–22],and nanorods [23–25], also exhibit unique optical prop-erties due to LSPR, and they are expected to provide ex-cellent performance as LSPR biosensors. Based on therequirements of biosensor applications [21, 26–29], effi-cient methods for fabricating these nanostructures withtunable plasmonic properties are desired.
These kinds of nanometer-sized metallic structuresare generally fabricated by conventional nano/micro-manufacturing processes, such as ultraviolet lithogra-phy (UVL) or electron beam lithography (EBL) [30–32]. These techniques are useful for the production ofwell-defined and precise nanometer-sized metallic struc-tures. However, these processes consist of complicatedprocedures, such as resist coating, pattern drawing, etch-ing, and developing, where expensive equipment andstringent process controls are necessary. To developvery simple and low-cost production processes, many re-searchers have studied self-organizing methods, such asthermal dewetting [18, 20, 33] and anodic aluminum ox-ide (AAO) templates [34–36]. These processes can beused to fabricate many nanostructures, such as nanodotsand nanoholes, through simple procedures. However, itis difficult to control the features of the nanostructuresformed from these self-organization processes.
A chemical lift-off method has been proposed as a sim-ple microfabrication process [37, 38]. This process is con-ducted by pressing a stamp onto a metal film coated ona substrate. A self-assembled monolayer coated on thestamp creates a strong bond with the metal film. Thebonded metal film is removed from the substrate with thestamp. Metal structures of nano/micro-size remain on thesubstrate. However, there are some disadvantages in thisprocess because it uses a high molecular chemical that re-quires careful handling as ink, and in addition, the metalremains on the stamp, which makes reuse difficult.
Therefore, in this study, a new chemical lift-off processthat uses an easy-to-handle organic solvent as ink and a
Int. J. of Automation Technology Vol.14 No.2, 2020 229
Fig. 1. Schematic diagram of the chemical lift-off process.
polymer film to remove the metal layer instead of trans-ferring metal to the stamp is proposed. This process isexpected to be advantageous in terms of safety and lessstamp damage and to achieve high efficiency and low cost.The objective of this work is to verify the feasibility of theproposed process and to demonstrate its capabilities forthe fabrication of various structures, such as metal lines,metal square film arrays, and metal dot arrays. In this pa-per, the details of the experimental method and results arepresented.
2. Experimental Methods
2.1. Examined Chemical Lift-Off ProcessFigure 1 illustrates the chemical lift-off process exam-
ined in this work. This process consists of the followingfive steps:
Step 1: Preparation of a substrateA quartz glass plate was used as the substrate.The thickness of the quartz glass plate was 1 mm,and it was cut to 12× 12 mm dimensions. Sur-face roughness was measured by atomic force mi-croscopy (AFM) and found to be Ra = 0.6 nm.It was cleaned in an ultrasonic acetone bath for15 min and air-dried. Subsequently, it was sub-jected to Ar (Argon) sputter etching for 2 min toremove residual acetone molecules from its sur-face.
Step 2: Chemical stampingA COP (cycloolefin polymer, ZF14-100, pro-duced by Zeon Corporation) film mold, whichwas fabricated by a hot-pressing method from asilicon mold, was used for the chemical stamp-ing. Details of the film mold preparation are ex-plained in the next section. Acetone was used
Fig. 2. Schematic diagram of the embossing process for thefabrication of a COP mold.
as a chemical ink in this process. Acetone wasdropped on the COP film mold and air-dried for4 min. Thereafter, the COP mold was pressed onthe etched quartz glass substrate with a load of20 N for 100 s, and subsequently, it was detachedfrom the quartz substrate.
Step 3: Deposition of the metal film
The quartz glass substrate was coated with an Aufilm of 10 nm thickness using a direct current(DC) sputter coater (IB-2, produced by Eiko En-gineering Co., Ltd.). The sputter gas was Ar, andthe pressure was 15 Pa. The accelerating voltagewas 0.7 kV, and the sputter current was kept at5 mA during sputter deposition. The distance be-tween the specimen and the Au target was 35 mm.The thickness of the Au film was controlled byadjusting the sputtering time.
Step 4: Coating with glue
A polyvinyl acetate (PVA)-based glue was coatedon the deposited Au film. The thickness of thePVA-based glue was about 1 mm. The coatedglue was cured at room temperature for 24 h.
Step 5: Selective peeling
After curing, the glue film was peeled off thesubstrate using tweezers. The Au film on theacetone stamped region was peeled off with theglue film because the stamped acetone reducedthe bonding strength between the substrate andthe Au film. Meanwhile, the Au film on the non-stamped region remained on the substrate, andnano/microstructures of thin Au film were formedon the substrate.
2.2. Preparation of the COP Film MoldFigure 2 illustrates the hot embossing process em-
ployed for the fabrication of the COP film mold. As il-lustrated in Fig. 2, a 100 μm thick COP film was placedon the silicon mother mold with supporting quartz glassplates placed on the top and the bottom of this tandem,and they were set in a hot press machine. The substrateand COP film were heated to 170◦C, and a pressure of172 kPa was applied. The pressure was held for 60 s, and
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Chemical Lift-Off Process Using Acetone Ink forEasy Fabrication of Metallic Nano/Microstructures
Fig. 3. Photographs of molds used for the experiment.(a) Silicon mother mold and (b) COP mold fabricated by hotembossing.
(a) AFM image of mold A (b) Height profile of mold A
(c) AFM image of mold B (d) Height profile of mold B
x(e) AFM image of mold C (f) Height profile of mold C
Fig. 4. AFM images and the height profiles of the COP filmmolds.
the hot press was subsequently cooled to room tempera-ture (around 20◦C) using a water-cooling system. There-after, the press pressure was released. Finally, the COPfilm was detached from the silicon mother mold.
Figure 3(a) shows the silicon mother mold used for thehot embossing process. Nine kinds of surface structureswith different sizes were fabricated by the photolithogra-phy method on the mother mold. Fig. 3(b) shows a COPfilm mold fabricated by the hot embossing process. Threeof the nine structures of the COP mold were examinedin the experiments. Fig. 4 shows the AFM images andthe cross-section profiles of these three mold structures.Line and space patterns (mold A) are shown in Figs. 4(a)and (b). The widths of the ridges were 2 μm, the depthsof the grooves were about 1 μm, and the pitches of thegrooves were 4 μm. Fine line and space patterns (mold B)are shown in Figs. 4(c) and (d). The widths of the ridgeswere 1 μm, the depths of the grooves were about 0.8 μm,
and the pitches of the grooves were 2 μm.It was found that the edges of the ridges of mold B were
rounder than those of mold A. This could be attributed tothe material flow of the COP film during hot embossing.When a viscous material is pressed into a narrow groove,the overhang depth depends on the width of the groove,viscosity, and surface tension of the material. The widthof mold B is half of that of mold A, and the overhangdepth of COP is smaller than mold A. Actually, the ridgeheight of mold A is about 1 μm, while that of mold B is0.2 μm. Therefore, it is considered that, in the case ofmold B, the COP film was not pressed to the bottom ofthe groove of the mother mold, but it ended in a state ofoverhanging in the groove and round ridges were formedas shown in Fig. 4(c). The pit array pattern (mold C) isshown in Figs. 4(e) and (f). The diameters of the pits were1.8 μm, the depths of the pits were about 0.85 μm, andthe distances between the centers of the adjacent pits were4 μm.
2.3. Ink of the Chemical StampingAs explained in Section 2.1, acetone was used as the
ink of the chemical stamping. It was selected fromeight kinds of organic solvents, which include acetone,ethanol, methanol, N-butanol, kerosene, dimethyl sulfox-ide, 4-hydroxy-4-methyl-2-pentanone, and aurum, by thefollowing procedure. Firstly, a quartz glass substrate wascleaned by Ar sputter etching to keep its surface condi-tions constant. Thereafter, its surface was pretreated bydropping the organic solvent on the surface and air-dryingit. Subsequently, an Au thin film with a thickness of10 nm was deposited on the substrate using a DC sputtercoater. Thereafter, the substrate was annealed at 900◦Cfor 30 min in air.
Figure 5 shows the scanning electron microscope(SEM) images of the annealed substrates. It was foundthat the coated Au thin film aggregated into many hemi-spherical dots due to a thermal dewetting mechanism, andthe dot size depended on the dropped chemical solventtype. As discussed in a former paper [39], the dot size,Di, depends on the contact angle between the substrateand the Au dots, and the average contact angle θ can bedetermined by solving the following equation.
f (θ) =1
sin3 θ(2−3cosθ + cos3 θ
)
=24At
πN
∑i=1
D3i
when 0 < θ <π2
. . . . (1)
where A is the area of observation by SEM, t is the thick-ness of the coated Au layer, and Di represents the diame-ters of the aggregated Au dots determined from the SEMmicrographs using a graphic analysis system.
Figure 6 shows the average diameter and contact anglefor each solvent. In this figure, Au dots on the substratespretreated with acetone, kerosene, and dimethyl sulfox-ide showed comparably larger contact angles than those
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Potejanasak, P. et al.
Fig. 5. SEM images of Au dots aggregated by thermal dewetting on the chemically pre-treated substrates.
Organic solvent used for pretreatment of substrate
Aver
age d
ot dia
meter
(nm)
Conta
ct an
gle (°
)
Average diameter Contact angle
Fig. 6. The average dot diameter and contact angle ofthe aggregated Au nanodots on quartz glass substrates pre-treated by various organic chemicals. (a) Sputter-etched,(b) acetone, (c) ethanol, (d) methanol, (e) N-Butanol,(f) kerosene, (g) dimethyl sulfoxide, (h) 4-hydroxy-4-methyl-2-pentanone, and (i) aurum.
of the substrates treated with other solvents. The adhe-sion between the substrate and Au is believed to have de-creased with an increase in the average contact angle, andselective peeling of the Au thin film became very easy.However, dimethyl sulfoxide is difficult to handle due toits toxicity. Kerosene has relatively low volatility and re-quires long drying time. Therefore, among these organicsolvents, acetone was chosen as the ink for the chemicalstamping process due to its high contact angle, low toxic-ity, and good volatility.
Fig. 7. AFM images and height profiles of the Au filmscoated on the chemically stamped substrates by the line andspace mold, where the thickness of the Au film was 10 nm.(a) and (b): mold A. (c) and (d): mold B.
3. Results and Discussion
3.1. Fabrication of Au Lines
Figure 7 shows the AFM images and height profiles ofthe surface of the Au films (10 nm thick) deposited on theacetone stamped substrates. Figs. 7(a) and (b) show thoseof mold A. It was found from the figures that a line and
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Chemical Lift-Off Process Using Acetone Ink forEasy Fabrication of Metallic Nano/Microstructures
Fig. 8. AFM images and height profiles of Au lines remain-ing on the quartz glass substrates after the peeling operation.(a) and (b): mold A. (c) and (d): mold B.
space pattern similar to mold A appeared on the surface ofthe deposited Au film. The Au films on the acetone bandwere considered to have been raised according to manystamping test results. The widths of the raised bands wereabout 2.4 μm, and the average width of the space bandswas about 1.2 μm. The distances between the peaks ofthe adjacent raised bands were about 4 μm, which arenearly the same as the pitches of the grooves of mold A.Figs. 7(c) and (d) show the AFM data of mold B. Sim-ilarly, a line and space pattern was found on the quartzglass substrates in Fig. 7(c). The widths of the raisedbands were about 1.3 μm and the widths of the spaceswere about 0.6 μm. The distances between the peaks ofthe adjacent raised bands were 2 μm, which are the sameas the pitches of the grooves of mold B.
Figure 8 shows the AFM images and height profilesalong the x-x′ line of the Au lines remaining on the quartzglass substrate after the peeling operation. Figs. 8(a)and (b) show images of those fabricated using mold A.It was found that parallel Au lines of 1 μm in width weresuccessfully fabricated on the surface of the quartz glasssubstrate. The average thickness of the Au lines wasabout 10 nm. The pitches of the Au lines were about4 μm, which corresponded to the pitches of the groovesof mold A. Similarly, Au lines were also successfully fab-ricated on a quartz glass substrate by the peeling opera-tion using mold B, as shown in Figs. 8(c) and (d). Theaverage width of the lines was about 600 nm and the av-erage thickness was about 10 nm. The pitches of the Aulines were 2 μm, which corresponded to the pitches ofthe grooves of mold B. It is noticeable that the Au film inthe raised regions was peeled from the substrate with thecured glue layers. The Au film in the valley region of themold remained on the quartz glass substrate and formedAu lines.
Fig. 9. AFM image and height profile along x-x′ of the Aufilm coated on a quartz glass substrate after chemical stamp-ing with a grid pattern, where the thickness of the Au filmwas 10 nm.
Fig. 10. AFM image and height profile of the Au squarefilm array fabricated on the quartz glass substrate.
3.2. Fabrication of Nano/Micro-Squares Patterns
Figure 9 shows an AFM image and a height profilealong the x-x′ line of the Au film coated on a quartz glasssubstrate after chemical stamping. In this experiment, thechemical stamping was conducted twice using a line andspace pattern mold identical to mold A to form a grid pat-tern. After the first stamping, the substrate was rotated for90◦ horizontally and a second stamping was conducted.The thickness of the Au film was 10 nm. It is found fromFig. 9 that the Au film was raised in the acetone grid pat-tern, and the height of the Au film on the stamped grid pat-tern was about 16 nm. This height is considerably smallerthan that in Fig. 7(b). This is presumed to be becausethe stamping is done twice to produce a lattice structure,but the detailed mechanism is not apparent at present. Itshould be studied in the future.
Figure 10 shows an AFM image and a height profilealong the x-x′ line of a Au square film array fabricatedby the peeling operation on the quartz glass substrate.Micrometer-sized Au square films were aligned in a reg-ular grid pattern remaining on the quartz glass substrate.The average size of the Au square films was 1.6×1.6 μm,and the average distance between the centers of the micro-squares was 4 μm, which corresponds to the distance be-tween the grooves of the COP mold A. The average heightof the Au square films was about 10 nm, which was thesame as the thickness of the deposited Au film layer. It isobserved that the Au film on the stamped grid pattern waspeeled off from the quartz glass substrate by the peelingoperation of the cured glue layer.
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Fig. 11. AFM image and height profile along x-x′ of an Aufilm coated on a quartz glass substrate after chemical stamp-ing of the hole grid pattern, where the thickness of Au filmwas 10 nm.
Fig. 12. AFM image and height profile of an Au dot arrayfabricated on the quartz glass substrate.
3.3. Fabrication of Nano/Microdot ArrayFigure 11 shows an AFM image and a height profile
along the x-x′ line of the Au film coated on a quartz glasssubstrate after chemical stamping using mold C. An arrayof circles surrounded by raised areas was found on thecoated Au film. The average diameter of the circles wasabout 2 μm, and the average distance between the centersof the pits was 4 μm, which corresponds to the sizes ofpits of mold C.
Figure 12 shows an AFM image and a height profilealong the x-x′ line of an Au dot array fabricated on aquartz glass substrate by the peeling operation. It is ap-parent that the Au film on the stamped pit pattern waspeeled off from the quartz glass substrate by the peel-ing operation of the cured glue layer. As a result, regu-larly aligned Au dots were successfully fabricated on thequartz glass substrate. The average diameter of the mi-crodots was around 2.0 μm, and the average height of thenanodots was 10 nm. The average distance between thecenters of the adjacent Au dots was 4 μm, which was thesame as that of the pits of the mold C.
3.4. Role of Acetone on the Selective PeelingFrom these experimental results, it was confirmed that
metal film structures of various micrometer-sized patternscan be fabricated by the chemical lift-off process. It wasfound that metal films coated on the stamped region werepeeled off with the glue, and the metal film shaped in thenegative pattern of the stamp remained on the substrate.The advantages of this process are that it does not requireexpensive equipment other than a sputter coater and that
Fig. 13. FTIR spectra of the COP film and quartz glassspecimens prepared by three different methods.
it does not use hazardous chemicals, such as acid or al-kali solutions. The fundamental mechanism of this pro-cess is the selective peeling of metal films on the chemicalstamped region. This is attributed to the bonding inhibi-tion between atoms of the deposited metal and the sub-strate by chemical stamping. Atoms on the surface ofthe substrate were activated and the surface energy wasexcited because the substrate was cleaned by Ar sputteretching prior to sputter deposition of the metal film. Asa result, strong bonding between the metal atoms and thesubstrate occurred, and a metal film on this area was notpeeled off. Meanwhile, the substrate surface of the chem-ically stamped region was covered with molecules trans-ferred from the COP mold, and the surface energy was re-duced. This resulted in a decrease in the bonding strengthof the deposited metal film, and the metal film was peeledoff easily with the PVA-based glue. It seemed as if the thinCOP layer adhered to the quartz glass due to the chemicalstamping because raised regions were observed on the Aufilm in Figs. 7, 9, and 11. However, no COP moleculeswere found on the substrate after chemical stamping.
Figure 13 shows the Fourier transform infrared spec-troscopy (FTIR) spectra of a fresh COP film and quartzglass specimens prepared by three different methods.These specimens were analyzed by the attenuated to-tal reflection (ATR) method to obtain only surface layerdata. The green curve is the spectrum of the quartz glasscleaned by Ar sputtering. It has a sharp peak at 1100 cm−1
that is indicated by a thick vertical dashed line, whichis attributed to the Si-O-Si bonding. The spectrum ofthe COP film (yellow) has peaks between 2800 cm−1
and 3000 cm−1. The thin vertical dashed lines indicatewavenumbers particular to acetone. The blue curve is aspectrum of a quartz glass specimen that was spotted withacetone and dried for 1 min. However, there are no peakson the blue curve that correspond with the thin dashedlines. Thus, a small amount of acetone remained on thequartz glass.
The red curve is a spectrum of a quartz glass speci-men that was stamped with a COP film, which was spot-ted with acetone and subsequently dried for 30 s beforestamping. As there are no peaks particular to the COP film
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Chemical Lift-Off Process Using Acetone Ink forEasy Fabrication of Metallic Nano/Microstructures
(2800–3000 cm−1) or acetone, the COP molecule was nottransferred to the quartz glass by the chemical stamping.Therefore, the acetone molecule did not dissolve the COP,which remains as nano-patterns on the substrate.
It is assumed that excess liquid acetone was removed bydrying, and a very thin acetone layer remained on the sur-face of the COP mold. The remaining acetone moleculeson the ridges of the COP mold contacted the quartz sub-strate by the stamping operation, which caused a reduc-tion in the surface energy of the quartz glass substrate.This resulted in a decrease in the bonding strength be-tween the deposited metal film and the quartz glass sub-strate.
Actually, Au lines with 600 nm width were fabricatedin the experiment. It is advantageous to generate a largedifference in the surface energy between the sputtered sur-face and the stamped surface to improve the accuracy andresolution of the selective peeling. For this purpose, itis necessary to find a substrate material and ink that canachieve a large reduction in the surface energy betweenthe sputter etching and chemical stamping.
4. Conclusions
For the development of efficient fabrication meth-ods for metallic nano/microstructures, a chemical lift-off process using acetone as the ink was proposed inthis study. Fabrication of several kinds of metallicnano/microstructures, such as Au line and space struc-tures, Au square film arrays, and Au dot arrays, wasdemonstrated. Important conclusions are summarized asfollows.
1. This process is characterized by the acetone stamp-ing on the substrate, which reduces the bondingstrength between the substrate and the depositedmetal film. Since lift-off is done by glue film, theremoved metal does not remain on the stamp. Thisresults in less stamp damage.
2. Acetone was selected as the ink of the proposedchemical lift-off process due to its large reduction incontact angle, low toxicity, and good volatility.
3. Acetone ink pasted on the COP stamp was dried, andexcess liquid acetone was removed before stamping.It was considered that only a few layers of acetonemolecular were transferred to the substrate, but theseacetone layers were effective for reducing the bond-ing strength between the substrate and the depositedAu film.
4. This drying method is advantageous in improving se-lective peeling accuracy and resolution.
5. This process does not require hazardous chemicalsor expensive equipment but can produce a metal filmstructure smaller than one micrometer by simple pro-cesses.
AcknowledgementsThe authors gratefully acknowledge the funding by the Grant-In-Aid for Scientific Research of JSPS (26249007 and 17H01240).
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Name:Potejana Potejanasak
Affiliation:Department of Industrial Engineering, School ofEngineering, University of Phayao
Address:19 Moo. 2, T. Maeka, A. Muang, Phayao 56000, ThailandBrief Biographical History:2000-2004 B.Eng. Student, Department of Production Engineering, KingMongkut’s Institute of Technology North Bangkok2004-2006 Service Engineer, Maintenance and Service Department,Sumisho Auto Leasing International Co., Ltd.2006-2009 M.Eng. Student, Department of Industrial Engineering,Kasetsart University2007-2008 Researcher, Mould and Die Industry Development Project,Research and Development Institute of Industrial Production Technology,Faculty of Engineering, Kasetsart University2009-2010 Project Coordinator, National Innovation Agency, Ministry ofScience and Technology, Thailand2010- Lecturer, Department of Industrial Engineering, School ofEngineering, University of Phayao2013-2016 D.Eng. Student, Department of Mechanical & ControlEngineering, Tokyo Institute of TechnologyMain Works:• P. Potejanasak, M. Yoshino, M. Terano, and M. Mita, “Efficientfabrication process of metal nanodot arrays using direct nanoimprintingmethod with a polymer mold,” Int. J. Automation Technol., Vol.9, No.6,pp. 629-635, 2015.• P. Potejanasak, M. Yoshino, and M. Terano, “Fabrication of metallicnanodot arrays using nano chemical stamping technique with a polymermold,” Int. J. Automation Technol., Vol.10, No.4, pp. 794-803, 2016.
Name:Truong Duc Phuc
Affiliation:School of Mechanical Engineering, Hanoi Uni-versity of Science and Technology
Address:1 Dai Co Viet Street, Hai Ba Trung District, Hanoi 11615, VietnamBrief Biographical History:2006 Received Bachelor’s degree from School of MechanicalEngineering, Hanoi University of Science and Technology2009 Received Master’s degree from Department of MechanicalEngineering, National Taiwan University of Science and Technology2014 Received Ph.D. from Department of Mechanical and ControlEngineering, Tokyo Institute of Technology2014- Lecturer, School of Mechanical Engineering, Hanoi University ofScience and TechnologyMain Works:• T. D. Phuc, M. Yoshino, A. Yamanaka, and T. Yamamoto, “Fabricationof Gold Nanodots on Plastic Films for Bio sensing,” Procedia CIRP, Vol.5,pp. 47-52, 2013.• T. D. Phuc, M. Terano, and M. Yoshino, “Fabrication of an ordered nanodot array by thermal dewetting on a patterned substrate,” ManufacturingLetter, Vol.2, Issue 2, pp. 60-63, 2014.
236 Int. J. of Automation Technology Vol.14 No.2, 2020
Chemical Lift-Off Process Using Acetone Ink forEasy Fabrication of Metallic Nano/Microstructures
Name:Motoki Terano
Affiliation:Lecturer, Department of Mechanical System En-gineering, Okayama University of Science
Address:1-1 Omachi, Kita-ku, Okayama-shi, Okayama 700-0005, JapanBrief Biographical History:2000-2004 B.E. Student, Department of Mechanical Engineering, NagoyaInstitute of Technology2004-2006 M.S. Student, Department of Engineering Physics, Electronicsand Mechanics, Nagoya Institute of Technology2006-2011 Ph.D. Student, Department of Engineering Physics, Electronicsand Mechanics, Nagoya Institute of Technology2011-2013 Postdoctoral Fellow, Department of Materials Science andEngineering, Nagoya University2013-2017 Assistant Professor, Department of Mechanical and ControlEngineering, Tokyo Institute of Technology2017- Lecturer, Department of Mechanical System Engineering, OkayamaUniversity of ScienceMain Works:• K. Kitamura and M. Terano, “Determination of local properties of plasticanisotropy in thick plate by small-cube compression test for precisesimulation of plate forging,” CIRP Annals – Manufacturing Technology,Vol.63, pp. 293-296, 2014.• T. D. Phuc, M. Terano, and M. Yoshino, “Fabrication of an ordered nanodot array by thermal dewetting on a patterned substrate,” ManufacturingLetters, Vol.2, Issue 2, pp. 60-63, 2014.Membership in Academic Societies:• Japan Society of Mechanical Engineers (JSME)• Japan Society for Technology of Plasticity (JSTP)• Japan Society for Precision Engineering (JSPE)• Iron and Steel Institute of Japan (ISIJ)• Society of Materials Science, Japan (JSMS)• Japan Society for Experimental Mechanics (JSEM)
Name:Takatoki Yamamoto
Affiliation:Associate Professor, Department of MechanicalEngineering, Tokyo Institute of Technology
Address:2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, JapanBrief Biographical History:1999 Received Dr.Eng. from Kyoto University1999- Special Post-Doctoral Researcher, RIKEN2000- Research Associate, Institute of Industrial Science, The Universityof Tokyo2009- Associate Professor, Tokyo Institute of TechnologyMain Works:• Applied nanofluidics for life science and medical applicationsMembership in Academic Societies:• Institute of Electrical Engineer of Japan (IEEJ)• Japan Society of Mechanical Engineers (JSME)
Name:Masahiko Yoshino
Affiliation:Professor, Department of Mechanical Engineer-ing, Tokyo Institute of Technology
Address:2-12-1 Ookayama, Meguro-ku, Tokyo 152-8552, JapanBrief Biographical History:1984 Graduated from Graduate School of Engineering and Science,Tokyo Institute of Technology1984- Research Staff, NKK Steel Co., Ltd.1987- Assistant Professor, Department of Mechanical EngineeringScience, Tokyo Institute of Technology2008- Professor, Department of Mechanical and Control Engineering,Tokyo Institute of TechnologyMain Works:• M. Yoshino, H. Ohsawa, and A. Yamanaka, “Rapid Fabrication of anordered nano-dot array by combination of nano plastic forming andannealing method,” J. Micromech. Microeng, Vol.21, 125017, 2011.Membership in Academic Societies:• Japan Society of Mechanical Engineers (JSME)• Japan Society for Technology of Plasticity (JSTP)• Japan Society for Precision Engineering (JSPE)• Japan Society for Abrasive Technology (JSAT)• Japan Society of Applied Physics (JSAP)• Iron and Steel Institute of Japan (ISIJ)
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