surface modification by plasma

8/13/2019 surface modification by plasma

1/8

High-efciency plasma surface modication of graphite-encapsulated magnetic nanoparticles

using a pulsed particle explosion technique

Teguh Endah Saraswati1,2, Shun Tsumura3, and Masaaki Nagatsu1

1Graduate School of Science and Technology, Shizuoka University, Hamamatsu 432-8561, Japan2Department of Chemistry, Faculty of Mathematics and Natural Sciences, Sebelas Maret University, Surakarta 57126, Indonesia3Graduate School of Engineering, Shizuoka University, Hamamatsu 432-8561, Japan

Received July 17, 2013; accepted September 22, 2013; published online December 30, 2013

A high-efciency surface modication of graphite-encapsulated iron compounds magnetic nanoparticles using an inductively coupled radio-

frequency plasma with a pulsed particle explosion technique was studied. A signicant increase in N 1s peak intensity in the X-ray photoelectron

spectroscopy spectra was obtained by applying a negative pulsed bias voltage of %1 kV to the substrate stage for 15 s or less at a repetition

frequency of 1 kHz and a duty ratio of 50% in ammonia plasma. The intensity of the N 1s peak and the N/C ratio of the nanoparticles treated in a

pulsed particle explosion system were 34 times higher than those of the particles treated without bias. The amino group population of

nanoparticles treated using the present technique was determined to be about 8.2 ' 104 molecules per nanoparticle, roughly four times higher than

that of particles treated without bias. The dispersion of the plasma-treated nanoparticles was signicantly improved compared with those of the

untreated and treated particles in the nonbiasing system. The surface structure analysis by transmission electron microscopy showed no

signicant damage on the structure or morphology of the treated nanoparticles, indicating that the present technique is applicable to the high-

efciency surface modication of magnetic nanoparticles. 2014 The Japan Society of Applied Physics

1. Introduction

Recently, carbon-coated magnetic nanoparticles have at-

tracted considerable interest in materials science research.

The incorporation of both metallic nanoparticles and carbon

in a stable coreshell system improves their advantageous

properties, which make them potentially applicable in various

applications such as magnetic data storage, magnetic uid,

magnetic inks,1) catalyst support,2) magnetic separation,

electrode, additives for many uses (i.e., as sintering agents

and propellants), conductive paste, conductive coating, and

biotechnological and biomedical applications.310)

Bare metallic nanoparticles have high reactivity and high

toxicity, which are limitations for realizing their practical

applications, such as instability under oxidation and degra-

dation conditions (i.e., in acids). The other disadvantages are

their easy agglomeration and unsupported-surface structure

for providing functional group attachment for absorbing

appropriate molecules. Consequently, coating bare metal-

magnetic nanoparticles with a protective shell is an

appropriate technique to overcome those limitations.

Compared with polymers and silica, carbon with the

graphite structure is a promising coating material for bio-

applications because of its high stability at high temperatureand pressure, and in various chemical and physical environ-

ments (i.e., acid or base media). Moreover, the graphite shell

allows for further functionalization with specic functional

groups and biomolecules. Unfortunately, graphite-encapsu-

lated magnetic nanoparticles conventionally prepared by

the arc-discharge method, generally disperse only in organic

solvents. This phenomenon makes them unsuitable for

bioapplications. To enhance nanoparticle biocompatibility,

surface modication processing has become a necessary

procedure before nanoparticles nd practical applications.

One of the efcient methods of surface modication

is plasma treatment, which has been commonly used for

many industrial applications. Plasma surface modication is

environmentally friendly with a short reaction time, and

provides various functional groups.11) Plasma processing can

markedly increase production if the system is optimized.

Recently, the plasma processing of magnetic materials has

drawn much attention with regard to nanoparticle surface

treatment for medical uses, such as drug delivery systems or

magnetic resonance imaging systems. There have been several

plasma reactor systems already developed for particle treat-

ment, such as the bell jar reactor,12,13) downstream reactor,14)

rotary drum reactor,15) plasma uidized bed reactor,1618)

circulating bed reactor,19,20) plasma batch reactor,21) plasma

downer reactor,22) and plasma reactor with a mechanical

vibrator such as an electromagnet12) or a stirrer.13)

The purpose of these plasma systems is to interface

particles with plasma species. An efcient interaction

between the particle surface and the plasma is the key to

achieve the maximum surface modication. Early attempts to

improve the dispersion of pigment particles were carried out

using plasma techniques.23,24) In the case of polymer webs,

the entire surface is exposed to plasma using conventional

drum- or batch-type plasma reactors.25) However, such

plasma reactors are often unsuitable for particle materials

owing to the lack of solid mixing.26)

As described in our previous paper,27) we successfully

modied graphite-encapsulated iron compound magnetic

nanoparticles deposited on a silicon substrate with amino

groups using Ar and NH3 plasmas in successive stages. Totreat the particles homogeneously, they should be placed on

the sample stage such that they are dispersed as widely as

possible. When the placement of the particle sample is not

performed well, the uniform treatment of the entire bulk of

particles is difcult to achieve because the modication will

likely take place only on the top layers of the sample, that is,

particles inside the bulk will be less exposed to the plasma

than particles at the surface of the bulk.

To enhance the interaction between the particles and the

plasma, a modied setup is required. We consider that the

particle explosion technique enables an enhanced surface

interaction between the particle samples and the plasma

species. Therefore, in the present study, we developed a

plasma reactor for particle treatment to explode the particles

inside the chamber by a negative pulsed biasing of the sample

stage during the plasma processing.

Japanese Journal of Applied Physics 53, 010205 (2014)

http://dx.doi.org/10.7567/JJAP.53.010205

SELECTED TOPICS IN APPLIED PHYSICS

Interactions between Plasmas and Nano-Interfaces

010205-1 2014 The Japan Society of Applied Physics
http://dx.doi.org/10.7567/JJAP.53.010205http://dx.doi.org/10.7567/JJAP.53.010205http://dx.doi.org/10.7567/JJAP.53.010205


2/8

2. Experimental procedure

2.1 Nanoparticle fabrication and plasma processing

setup

Graphite-encapsulated iron compound magnetic nanoparticles

were prepared by the arc discharge method,28,29) which has

already been described in previous papers.27,30) The character-

istics of the magnetic nanoparticles, such as magnetic prop-

erties or crystalline structures, have been described in a pre-

vious paper.30) Following nanoparticle synthesis, the nano-

particles are treated using a radio-frequency (RF) inductively

coupled plasma device. A schematic view of the chamber is

shown in Fig. 1. The stainless-steel chamber is 200 mm in

both diameter and height. The water-cooling copper pipe

helical antenna with a coil diameter of 100 mm and a pipe

diameter of 20mm was wound around the quartz bell jar

(110 mm in outer diameter and 260 mm in height) mounted on

the stainless-steel chamber. The helical antenna was coupled

to an RF power generator at 13.56 MHz via a matching

network. The typical input RF power was about 80 W.

The chamber used in this work was modied by adding themetal substrate for the sample stage inside the chamber. The

metal substrate of 10 mm diameter was attached to the center

of the glass dish placed at z= 2cm (see Fig. 1), where

z= 0 is dened as the center of the helical antenna on its

axial axis. To conne the nanoparticles exploded by applying

bias, a glass tube with a diameter of 80 mm and a height of

60 mm was placed on the glass dish.

In the experiment, rstly, we put the particle sample (about

5 mg) on the metal substrate. The chamber was evacuated to a

base pressure of approximately 103 Pa. After the vacuum

evacuation, NH3 gas was introduced into the chamber and

kept at 50 Pa. During the plasma processing, the gate chamber

was closed to prevent the nanoparticles from owing to the

turbo pump system. The biasing conditions were as follows: a

substrate pulse biasing of1 kV was applied at a repetition

frequency of 1 kHz and a duty ratio of 50%. The negative

pulsed bias voltage was turned on immediately after switching

the plasma on. Generally, it will take time to match the input

and reection powers before applying the pulsed bias to the

substrate. The bias time tb was varied from 0 to 60 s. After

biasing off, the plasma was kept turned on up to the desired

plasma treatment time tp of 10min. The explosion of the

particles by applying pulsed biasing was visually observed

and recorded using a high-resolution digital camera (Nikon

D90) at a capture speed of 24fps. The videos were then

processed using the software VirtualDub to add the timestamp

and obtain sequential images.

2.2 X-ray photoelectron spectroscopy and transmission

electron microscopy analysis

Following the plasma treatment, the samples were further

analyzed by X-ray photoelectron spectroscopy (XPS) per-

formed using a Shimadzu ESCA-3400 with a Mg K X-ray

source and high-resolution transmission electron microscopy

(HR-TEM) performed using a JEM-2100F at an acceleration

voltage of 200 kV.

2.3 Estimation of amino group population

The amino group population of the plasma-treated nano-

particles was analyzed by the chemical derivatization method

using sulfosuccinimidyl 6-[3A(2-pyridyldithio)-propion-

amido] hexanoate (sulfo-LC-SPDP) according to the specic

chemical procedure.3133) The modied nanoparticles

(250 g) were suspended by bath sonication in 200 l of

10 mM sulfo-LC-SPDP in phosphate buffer saline (PBS) and

reacted for 30 min under light shielding conditions, repeating

the ultrasonication every 5 min. The treated nanoparticles

were washed three times with PBS through ultrasonication

and centrifugation and collected magnetically. The centrifu-

gation was performed for 5 min with a gravitational force of

20,400g (14,000 rpm). The nanoparticles with sulfo-LC-

SPDP complexes were then reacted with 300 l of 20 mM

dithiothreitol (DTT) in PBS and reacted under light shielding

Fig. 1. (Color online) Schematic view of experimental setup: (1) quartz bell jar, (2) sample stage, (3) copper coil connected to the water cooling system,(4) pressure gauge, (5) leaking valve, (6) gas inlet, (7) gas outlet connected to the turbo and rotary pump, and (8) biasing power supply. The black rectangle

represents the timeline of experimental stages during plasma processing;tp and tb represent the total time for plasma treatment and the initial time for biasing,

respectively.

Jpn. J. Appl. Phys. 53, 010205 (2014) SELECTED TOPICS IN APPLIED PHYSICS



3/8

conditions, repeating the ultrasonication every 5 min. After a

15 min reaction, 5 min centrifugation at 20,400g (14000 rpm)

was performed and the cleavage product pyridine-2-thione

liberated from the sulfo-LC-SPDP present in the recovered

supernatant liquid, was determined by spectrophotometry

at 343 nm. The number of amino groups in 250 g of the

modied nanoparticles was quantitatively determined from

the calibration curve or by theoretical evaluation using theextinction coefcient of pyridine-2-thione at 343 nm: 8.08

103 M1 cm1. The number of amino groups per nanoparticle

was calculated when the number of nanoparticles per gram

was 1.14 1014. This number was estimated by measuring

the ratio of the mass of the nanoparticles to their volume

under the assumption that the nanoparticles have a regular

spherical shape mainly of 20 nm diameter determined from

the nanoparticle size distribution taken by HR-TEM.27,30)

2.4 Dispersion property

The nanoparticle dispersion before and after the plasma

treatment in both cases with and without the biasing systemwas also observed. The observation was performed by

dispersing equal numbers of nanoparticles in the same

volume of distilled water by ultrasonication for about 5 min.

3. Results and discussion

The present study was started by preparing nanoparticle

samples by the arc discharge method. The TEM images and

EDS proles of successfully fabricated nanoparticles are

shown in Fig. 2. Using TEM, we conrmed that iron com-

pound magnetic nanoparticles are clearly encapsulated by

graphitic carbon. This result shows good agreement with the

EDS proles of the selected particles that reveal at least three

possible phases: particles that exhibit the presence of O, Fe,

and C. The interplanar distances of the graphite lattice and

iron fringes are about 0.34 and 0.202 nm, respectively.

Following the nanoparticle fabrication, we placed nano-

particle samples (about 5 mg) on the metal substrate of the

sample holder located at the center of the glass dish. After

applying a pulse bias with a voltage of1 kV, a frequency of

1 kHz, and a duty ratio of 50%, the particles were exploded,

as shown in the successive images in Fig.3. These sequential

images were captured during the pulsed biasing. The rst

image (left top) in Fig. 3shows the condition before starting

the experiment (plasma OFF). The next image shows the

situation just after turning the plasma on. Then, it generallytook time to produce a stable plasma. Until the time of

turning the bias on, the sample particles are still in the metal

stage. Plasma generation will be easily achieved if the

matching is adjusted at the desired power beforehand. The

shorter time interval for turning on the bias provides an

effective interaction between the plasma and the particle

sample because the lifetime of an NH2radical is short (a few

microseconds).3436) The lifetime of these plasma species is

important because we used the no-ow gas condition, that is,

the chamber gate valve was closed during plasma treatment,

maintaining a pressure at 50 Pa. The negative pulsed bias

voltage was turned on about 11.4 s after turning on the

plasma. At the biasing-on time, the particles started to

explode and dropped back to the substrate stage after half

a second. After a certain biasing time (called tb), the bias

voltage was turned off, but the plasma treatment was con-

tinued without biasing up to the desired treatment timetp

. For

clarity, red dashed lines are added in the pictures to show

when and how the particles began to y and ended up.

In Fig. 4, we summarized the phenomenon observed in

Fig.3as the temporal behavior of the height changes of the

(a) (b)

Intensity

(arb.unit) (d)(c)

Fig. 2. (a) Low- and (b) high-magnication TEM images of the graphite-

encapsulated iron compound nanoparticle successfully fabricated by arc

discharge, (c) energy-dispersive X-ray spectra of the synthesized

nanoparticles, and (d) magnied image showing the interplanar distance of

graphite coating and iron core.

Fig. 3. (Color online) Time-sequential images of particle-explosion event

during biased-plasma processing.




4/8

exploding particles, attb= 15 s andtp= 3 min. The height ofthe exploding particles was measured as the highest position

taken from each image frame. The inset gure shows a

magnied view of the peak area. The letters shown in Fig. 4

denote the main events. A and B represent the timer ON

and plasma ON, which correspond to the rst (0.000 s) and

second (0.417 s) images in Fig.3, respectively. C represents

the time when the biasing was turned on, shown in the fourth

image (11.791 s) in Fig.3. The gap between B and C

indicates the time required for the impedance matching

between the RF source and the plasma. The particles started

to explode at C, reached their maximum height at D

(12.125 s), and ended up at E (12.5 s). F represents the time

when the bias was turned off after 15 s of having the bias

turned on, and G represents the time when the plasma was

switched off after 180 s (3 min).

The explosion event is explained by the ion bombardment

mechanism. After turning on the biasing, the pulsed negative

high voltage caused a high electric eld in the sheath between

the plasma and the substrate. The existence of a high electric

eld caused the ions in the plasma to accelerate toward

the substrate where the particles were placed. Because the

particles were placed on the stage in powder form, once

the powder was bombarded by plasma ions, the particles

spontaneously popped out and exploded upwards in a very

fast manner. This phenomenon is similar to a conventionalion sputtering event. The ion bombardment energy depends

on the difference in potential between the plasma and the

substrate (V= Vp Vsub) and is subsequently expressed as

e(Vp Vsub). In this study, if the estimated plasma potential

Vpis more or less on the order of 10 V, the ion bombardment

energy when biasing is turned on is approximately 1 keV,

estimated from a biasing voltage of1 kV. This proposed

mechanism also enables agglomerated nanoparticles to

separate into ne particles during the explosion process. By

using a small (diameter 10 mm) metal substrate with a high

negative voltage, the particles explode and do not return back

to the substrate but fall on the glass dish area surrounding the

metal substrate owing to gravitational force. The dynamic

behavior of the particles and the forces acting on them under

biasing have been discussed in several papers,3741) which are

beyond the scope of our present paper.

After the plasma treatment, the treated particles were

characterized by XPS. Figure5 shows the data set of the

N 1s peak of the XPS proles with various biasing times tbreferred to as the C F range (see Fig. 4). The observed

N 1s peaks located at approximately 399.8 eV are considered

as a signal of the nitrogen-containing group for the amino

group, which was successfully grafted on the surface.Figure5 shows the N 1s spectra at different biasing times

oftb= 0 (no biasing), 2, 15, 30, and 60 s, each of which was

obtained for various plasma treatment times tp of up to

30 min. Comparing the biasing system with the nonbiasing

system (tb= 0 s), the intensity of the N 1s peak of the biasing

system (tb= 2, 15, 30, and 60 s) is signicantly increased.

For example, the intensity of the N 1s peak of the nano-

particles treated in the biasing system (tb= 15s) is raised to

about 34 times higher than those in the nonbiasing system

(tb= 0 s) for short plasma treatment times tp of up to 3 min.

This indicates that the plasma treatment with applied biasing

had a signicant effect of increasing N 1s peak intensity.

These increases in the N 1s peak intensity are supposed to be

due to the enhancement of the efcient interaction between

the particles and the plasma species, particularly nitrogen-

containing species, during an explosion event.

Fig. 4. (Color online) Explosion height vs plasma treatment time under

experimental conditions oftb=15s; tp=3 min. A: timer ON. B: plasma

ON. C: bias ON, explosion starts. D: maximum height of explosion event.

E: explosion ends. F: bias OFF. G: plasma OFF.

Intensity

(arb.unit)

Intensity

(arb.un

it)

Fig. 5. (Color online) Comparison of N 1s XPS proles for various

plasma-treatment times (tp=0, 1, 2, 3, 6, 8, 10, 15, and 30 min) and biasing

times (tb=0, 2, 15, 30, and 60s).




5/8


6/8


7/8

to the treated nanoparticles under various (tb, tp) conditions

of (0s, 3 min), (2s, 3 min), (15 s, 3 min), (30 s, 3 min),

(60 s, 3 min), and (15 s, 30 min). All of the images conrm that

no damage or destruction was induced in the nanoparticle

structure after performing the plasma treatment in the

nonbiasing or biasing system. The structure of the graphite

layers was found to be stable under all the experimental

conditions. Similarly to the graphite coating, the iron com-pound core also remained encapsulated inside the graphite

layers even when the particles were subjected to long-term

plasma treatment, as shown in Fig. 9(f ). This result indicates

that the pulsed-biasing particle explosion technique per-

formed in the present study is highly efcient in amino group

functionalization. Furthermore, it is also suitable for surface

modication, particularly for powder samples because of its

ability to retain the structural stability of nanoparticles.

4. Conclusions

The surface of graphite-encapsulated iron compound mag-

netic nanoparticles fabricated by arc discharge was success-fully modied by a pulsed particle explosion technique. This

technique was performed by applying a high negative bias of

1 kV to the substrate stage for 260 s at a repetition fre-

quency of 1 kHz and a duty ratio of 50% in ammonia plasma

generated using a radio frequency inductively coupled

plasma device. The intensity of the N 1s peak in the XPS

spectrum of the nanoparticles treated in the biasing system

was three to four times higher than that treated in the

nonbiasing system owing to the enhancement of the interac-

tion between the nanoparticles and the plasma species. The

present results also indicate the efcient enhancement of

amino group modication by approximately fourfold from

about 1.9 104 molecules/nanoparticle in the case of

(tb= 0 s, tp= 3 min) to 8.2 104 molecules/nanoparticle

in the case of (tb= 15s, tp= 3 min) by the negative pulsed

biasing during the NH3 plasma processing. Moreover, the

results also showed that the dispersion of the treated nano-

particles in biasing system was improved compared with

those of the untreated and treated samples in the nonbiasing

system.

In addition, analysis by HR-TEM showed no signicant

damage on the nanoparticle structures, indicating that the

present technique is suitable mainly for the surface mod-

ication of particle samples owing to its high efciency in

surface modication without causing any signicant changeor destruction of the structural and morphological properties.

Acknowledgments

This work was supported in part by a Grant-in-Aid for

Scientic Research (No. 2110010) from the Japan Society for

the Promotion of Science (JSPS). The authors would like to

thank Associate Professor A. Ogino of Shizuoka University

for technical assistance in the plasma chamber development

and UVvis absorption spectroscopy measurement.

1) M. E. McHenry, S. A. Majetich, and E. M. Kirkpatrick,Mater. Sci. Eng. A

204, 19 (1995).

2) L. Kong, X. Lu, X. Bian, W. Zhang, and C. Wang,ACS Appl. Mater.

Interfaces 3 , 35 (2011).

3) G. Pastorin, Pharmacol. Res. 26 , 746 (2009).

4) Q. A. Pankhurst, N. T. K. Thanh, S. K. Jones, and J. Dobson,J. Phys. D42,

224001 (2009).

5) Q. A. Pankhurst, J. Connolly, S. K. Jones, and J. Dobson,J. Phys. D 36,

R167 (2003).

6) A.-H. Lu, E. L. Salabas, and F. Schth,Angew. Chem., Int. Ed. 46, 1222

(2007).

7) S. Kim, E. Shibata, R. Sergiienko, and T. Nakamura,Carbon 46, 1523

(2008).

8) A. Ito, M. Shinkai, H. Honda, and T. Kobayashi,J. Biosci. Bioeng. 100, 1

(2005).

9) C. C. Berry and A. S. G. Curtis, J. Phys. D 36, R198 (2003).

10) C. C. Berry, J. Phys. D 42, 224003 (2009).

11) C. Chen, A. Ogino, X. Wang, and M. Nagatsu,Appl. Phys. Lett. 96, 131504

(2010).

12) A. B. Garca, A. Martnez-Alonso, C. A. Leon y Leon, and J. M. D. Tascn,

Fuel77 , 613 (1998).

13) J. P. Boudou, A. Martinez-Alonzo, and J. M. D. Tascon,Carbon 38 , 1021

(2000).

14) D. Shi and P. He,Rev. Adv. Mater. Sci. 7 , 97 (2004).

15) V. Brser, M. Heintze, W. Brandl, G. Marginean, and H. Bubert, Diamond

Relat. Mater. 13, 1177 (2004).

16) F. Bretagnol, M. Tatoulian, F. Are-Khonsari, G. Lorang, and J. Amouroux,

React. Funct. Polym. 61 , 221 (2004).

17) F. Are-Khonsari, M. Tatoulian, F. Bretagnol, O. Bouloussa, and F.

Rondelez,Surf. Coatings Technol. 200, 14 (2005).

18) M. Tatoulian, F. Brtagnol, F. Are-Khonsari, J. Amouroux, O. Bouloussa,

F. Rondelez, A. J. Paul, and R. Mitchell, Plasma Processes Polym. 2 , 38

(2005).

19) S. H. Jung, S. H. Park, D. H. Lee, and S. D. Kim, Polym. Bull. 47, 199

(2001).

20) S. H. Jung, S. H. Park, and S. D. Kim,J. Chem. Eng. Jpn. 37, 166 (2004).

21) J.-W. Kim, Y.-S. Kim, and H.-S. Choi, Korean J. Chem. Eng. 19, 632

(2002).

22) C. Arpagaus, A. Rossi, and P. Rudolf von Rohr,Appl. Surf. Sci. 252, 1581

(2005).

23) T. Ihara, S. It, and M. Kiboku, Chem. Lett. 15, 675 (1986).

24) K. Tsutsui, K. Nishizawa, and S. Ikeda, J. Coatings Technol.60 , 107

(1988).25) M. R. Wertheimer, H. R. Thomas, M. J. Perri, J. E. Klemberg-Sapieha, and

L. Martinu, Pure Appl. Chem. 68, 1047 (1996).

26) C. Arpagaus, Dr. Thesis, Swiss Federal Institute of Technology Zurich,

Zurich (2005).

27) T. E. Saraswati, T. Matsuda, A. Ogino, and M. Nagatsu,Diamond Relat.

Mater. 20, 359 (2011).

28) M. Nagatsu, T. Yoshida, M. Mesko, A. Ogino, T. Matsuda, T. Tanaka, H.

Tatsuoka, and K. Murakami, Carbon 44, 3336 (2006).

29) Y. Saito, T. Yoshikawa, M. Okuda, N. Fujimoto, S. Yamamuro, K. Wakoh,

K. Sumiyama, K. Suzuki, A. Kasuya, and Y. Nishina, Chem. Phys. Lett.

212, 379 (1993).

30) T. E. Saraswati, A. Ogino, and M. Nagatsu, Carbon 50, 1253 (2012).

31) J. Carlsson, H. Drevin, and R. Axn, Biochem. J.173, 723 (1978).

32) G. Hermanson, Bioconjugate Techniques (Academic Press, New York,

2008) 2nd ed., p. 277.

33) B. Yoza, A. Arakaki, and T. Matsunaga, J. Biotechnol. 101, 219 (2003).34) X.-Y. Gong, X. R. Duan, H. Lange, and A. A. Meyer-Path,Chin. Phys. Lett.

18, 939 (2001).

35) E. R. Fisher,Plasma Processes Polym. 1 , 13 (2004).

36) A. Fateev, F. Leipold, Y. Kusano, B. Stenum, E. Tsakadze, and H. Bindslev,

Plasma Processes Polym. 2 , 193 (2005).

37) T. Moriya, M. Shimada, K. Okuyama, and H. Setyawan,Jpn. J. Appl. Phys.

44, 4871 (2005).

38) C. M. Tico, A. Dyson, and P. W. Smith,Plasma Sources Sci. Technol. 13,

395 (2004).

39) J. Liu, D. Wang, T. C. Ma, Y. Gong, Q. Sun, J. X. Ma, and C. X. Yu,Phys.

Plasmas6 , 1405 (1999).

40) V. E. Fortov, A. V. Ivlev, S. A. Khrapak, A. G. Khrapak, and G. E. Morll,

Phys. Rep. 421, 1 (2005).

41) H. Kersten, H. Deutsch, E. Stoffels, W. W. Stoffels, and G. M. W. Kroesen,

Int. J. Mass Spectrom. 223224, 313 (2003).

42) M. Krl, A. Ogino, and M. Nagatsu, J. Phys. D 41 , 105213 (2008).


http://dx.doi.org/10.1016/0921-5093(95)09930-1http://dx.doi.org/10.1016/0921-5093(95)09930-1http://dx.doi.org/10.1016/0921-5093(95)09930-1http://dx.doi.org/10.1021/am101077ahttp://dx.doi.org/10.1021/am101077ahttp://dx.doi.org/10.1021/am101077ahttp://dx.doi.org/10.1021/am101077ahttp://dx.doi.org/10.1007/s11095-008-9811-0http://dx.doi.org/10.1007/s11095-008-9811-0http://dx.doi.org/10.1007/s11095-008-9811-0http://dx.doi.org/10.1088/0022-3727/42/22/224001http://dx.doi.org/10.1088/0022-3727/42/22/224001http://dx.doi.org/10.1088/0022-3727/42/22/224001http://dx.doi.org/10.1088/0022-3727/42/22/224001http://dx.doi.org/10.1088/0022-3727/36/13/201http://dx.doi.org/10.1088/0022-3727/36/13/201http://dx.doi.org/10.1088/0022-3727/36/13/201http://dx.doi.org/10.1088/0022-3727/36/13/201http://dx.doi.org/10.1002/anie.200602866http://dx.doi.org/10.1002/anie.200602866http://dx.doi.org/10.1002/anie.200602866http://dx.doi.org/10.1002/anie.200602866http://dx.doi.org/10.1016/j.carbon.2008.05.027http://dx.doi.org/10.1016/j.carbon.2008.05.027http://dx.doi.org/10.1016/j.carbon.2008.05.027http://dx.doi.org/10.1016/j.carbon.2008.05.027http://dx.doi.org/10.1263/jbb.100.1http://dx.doi.org/10.1263/jbb.100.1http://dx.doi.org/10.1263/jbb.100.1http://dx.doi.org/10.1263/jbb.100.1http://dx.doi.org/10.1088/0022-3727/36/13/203http://dx.doi.org/10.1088/0022-3727/36/13/203http://dx.doi.org/10.1088/0022-3727/36/13/203http://dx.doi.org/10.1088/0022-3727/42/22/224003http://dx.doi.org/10.1088/0022-3727/42/22/224003http://dx.doi.org/10.1088/0022-3727/42/22/224003http://dx.doi.org/10.1063/1.3377007http://dx.doi.org/10.1063/1.3377007http://dx.doi.org/10.1063/1.3377007http://dx.doi.org/10.1063/1.3377007http://dx.doi.org/10.1016/S0016-2361(97)00111-7http://dx.doi.org/10.1016/S0016-2361(97)00111-7http://dx.doi.org/10.1016/S0016-2361(97)00111-7http://dx.doi.org/10.1016/S0008-6223(99)00209-2http://dx.doi.org/10.1016/S0008-6223(99)00209-2http://dx.doi.org/10.1016/S0008-6223(99)00209-2http://dx.doi.org/10.1016/S0008-6223(99)00209-2http://dx.doi.org/10.1590/S1516-14392004000100014http://dx.doi.org/10.1590/S1516-14392004000100014http://dx.doi.org/10.1590/S1516-14392004000100014http://dx.doi.org/10.1016/j.diamond.2003.10.061http://dx.doi.org/10.1016/j.diamond.2003.10.061http://dx.doi.org/10.1016/j.diamond.2003.10.061http://dx.doi.org/10.1016/j.diamond.2003.10.061http://dx.doi.org/10.1016/j.reactfunctpolym.2004.06.003http://dx.doi.org/10.1016/j.reactfunctpolym.2004.06.003http://dx.doi.org/10.1016/j.reactfunctpolym.2004.06.003http://dx.doi.org/10.1016/j.surfcoat.2005.02.184http://dx.doi.org/10.1016/j.surfcoat.2005.02.184http://dx.doi.org/10.1016/j.surfcoat.2005.02.184http://dx.doi.org/10.1002/ppap.200400029http://dx.doi.org/10.1002/ppap.200400029http://dx.doi.org/10.1002/ppap.200400029http://dx.doi.org/10.1002/ppap.200400029http://dx.doi.org/10.1007/s002890170012http://dx.doi.org/10.1007/s002890170012http://dx.doi.org/10.1007/s002890170012http://dx.doi.org/10.1007/s002890170012http://dx.doi.org/10.1252/jcej.37.166http://dx.doi.org/10.1252/jcej.37.166http://dx.doi.org/10.1252/jcej.37.166http://dx.doi.org/10.1007/BF02699309http://dx.doi.org/10.1007/BF02699309http://dx.doi.org/10.1007/BF02699309http://dx.doi.org/10.1007/BF02699309http://dx.doi.org/10.1016/j.apsusc.2005.02.099http://dx.doi.org/10.1016/j.apsusc.2005.02.099http://dx.doi.org/10.1016/j.apsusc.2005.02.099http://dx.doi.org/10.1016/j.apsusc.2005.02.099http://dx.doi.org/10.1246/cl.1986.675http://dx.doi.org/10.1246/cl.1986.675http://dx.doi.org/10.1246/cl.1986.675http://dx.doi.org/10.1351/pac199668051047http://dx.doi.org/10.1351/pac199668051047http://dx.doi.org/10.1351/pac199668051047http://dx.doi.org/10.1016/j.diamond.2011.01.027http://dx.doi.org/10.1016/j.diamond.2011.01.027http://dx.doi.org/10.1016/j.diamond.2011.01.027http://dx.doi.org/10.1016/j.diamond.2011.01.027http://dx.doi.org/10.1016/j.carbon.2006.06.005http://dx.doi.org/10.1016/j.carbon.2006.06.005http://dx.doi.org/10.1016/j.carbon.2006.06.005http://dx.doi.org/10.1016/0009-2614(93)89341-Ehttp://dx.doi.org/10.1016/0009-2614(93)89341-Ehttp://dx.doi.org/10.1016/0009-2614(93)89341-Ehttp://dx.doi.org/10.1016/j.carbon.2011.10.044http://dx.doi.org/10.1016/j.carbon.2011.10.044http://dx.doi.org/10.1016/j.carbon.2011.10.044http://dx.doi.org/10.1016/S0168-1656(02)00342-5http://dx.doi.org/10.1016/S0168-1656(02)00342-5http://dx.doi.org/10.1016/S0168-1656(02)00342-5http://dx.doi.org/10.1088/0256-307X/18/7/331http://dx.doi.org/10.1088/0256-307X/18/7/331http://dx.doi.org/10.1088/0256-307X/18/7/331http://dx.doi.org/10.1002/ppap.200400011http://dx.doi.org/10.1002/ppap.200400011http://dx.doi.org/10.1002/ppap.200400011http://dx.doi.org/10.1002/ppap.200400051http://dx.doi.org/10.1002/ppap.200400051http://dx.doi.org/10.1002/ppap.200400051http://dx.doi.org/10.1143/JJAP.44.4871http://dx.doi.org/10.1143/JJAP.44.4871http://dx.doi.org/10.1143/JJAP.44.4871http://dx.doi.org/10.1088/0963-0252/13/3/005http://dx.doi.org/10.1088/0963-0252/13/3/005http://dx.doi.org/10.1088/0963-0252/13/3/005http://dx.doi.org/10.1088/0963-0252/13/3/005http://dx.doi.org/10.1063/1.873389http://dx.doi.org/10.1063/1.873389http://dx.doi.org/10.1063/1.873389http://dx.doi.org/10.1063/1.873389http://dx.doi.org/10.1016/j.physrep.2005.08.007http://dx.doi.org/10.1016/j.physrep.2005.08.007http://dx.doi.org/10.1016/j.physrep.2005.08.007http://dx.doi.org/10.1016/S1387-3806(02)00867-9http://dx.doi.org/10.1016/S1387-3806(02)00867-9http://dx.doi.org/10.1016/S1387-3806(02)00867-9http://dx.doi.org/10.1016/S1387-3806(02)00867-9http://dx.doi.org/10.1016/S1387-3806(02)00867-9http://dx.doi.org/10.1088/0022-3727/41/10/105213http://dx.doi.org/10.1088/0022-3727/41/10/105213http://dx.doi.org/10.1088/0022-3727/41/10/105213http://dx.doi.org/10.1088/0022-3727/41/10/105213http://dx.doi.org/10.1016/S1387-3806(02)00867-9http://dx.doi.org/10.1016/j.physrep.2005.08.007http://dx.doi.org/10.1063/1.873389http://dx.doi.org/10.1063/1.873389http://dx.doi.org/10.1088/0963-0252/13/3/005http://dx.doi.org/10.1088/0963-0252/13/3/005http://dx.doi.org/10.1143/JJAP.44.4871http://dx.doi.org/10.1143/JJAP.44.4871http://dx.doi.org/10.1002/ppap.200400051http://dx.doi.org/10.1002/ppap.200400011http://dx.doi.org/10.1088/0256-307X/18/7/331http://dx.doi.org/10.1088/0256-307X/18/7/331http://dx.doi.org/10.1016/S0168-1656(02)00342-5http://dx.doi.org/10.1016/j.carbon.2011.10.044http://dx.doi.org/10.1016/0009-2614(93)89341-Ehttp://dx.doi.org/10.1016/0009-2614(93)89341-Ehttp://dx.doi.org/10.1016/j.carbon.2006.06.005http://dx.doi.org/10.1016/j.diamond.2011.01.027http://dx.doi.org/10.1016/j.diamond.2011.01.027http://dx.doi.org/10.1351/pac199668051047http://dx.doi.org/10.1246/cl.1986.675http://dx.doi.org/10.1016/j.apsusc.2005.02.099http://dx.doi.org/10.1016/j.apsusc.2005.02.099http://dx.doi.org/10.1007/BF02699309http://dx.doi.org/10.1007/BF02699309http://dx.doi.org/10.1252/jcej.37.166http://dx.doi.org/10.1007/s002890170012http://dx.doi.org/10.1007/s002890170012http://dx.doi.org/10.1002/ppap.200400029http://dx.doi.org/10.1002/ppap.200400029http://dx.doi.org/10.1016/j.surfcoat.2005.02.184http://dx.doi.org/10.1016/j.reactfunctpolym.2004.06.003http://dx.doi.org/10.1016/j.diamond.2003.10.061http://dx.doi.org/10.1016/j.diamond.2003.10.061http://dx.doi.org/10.1590/S1516-14392004000100014http://dx.doi.org/10.1016/S0008-6223(99)00209-2http://dx.doi.org/10.1016/S0008-6223(99)00209-2http://dx.doi.org/10.1016/S0016-2361(97)00111-7http://dx.doi.org/10.1063/1.3377007http://dx.doi.org/10.1063/1.3377007http://dx.doi.org/10.1088/0022-3727/42/22/224003http://dx.doi.org/10.1088/0022-3727/36/13/203http://dx.doi.org/10.1263/jbb.100.1http://dx.doi.org/10.1263/jbb.100.1http://dx.doi.org/10.1016/j.carbon.2008.05.027http://dx.doi.org/10.1016/j.carbon.2008.05.027http://dx.doi.org/10.1002/anie.200602866http://dx.doi.org/10.1002/anie.200602866http://dx.doi.org/10.1088/0022-3727/36/13/201http://dx.doi.org/10.1088/0022-3727/36/13/201http://dx.doi.org/10.1088/0022-3727/42/22/224001http://dx.doi.org/10.1088/0022-3727/42/22/224001http://dx.doi.org/10.1007/s11095-008-9811-0http://dx.doi.org/10.1021/am101077ahttp://dx.doi.org/10.1021/am101077ahttp://dx.doi.org/10.1016/0921-5093(95)09930-1http://dx.doi.org/10.1016/0921-5093(95)09930-1


8/8

Teguh Endah Saraswati is currently a Lecturer and

Researcher in Chemistry Department, Mathematics

and Natural Sciences Faculty, Sebelas Maret Uni-

versity, Indonesia. She received Master of Science

degree in chemistry from Nagoya University in

2009, which was supported by Panasonic Scholar-

ship Program. In 2012, she completed the doctoral

program, which was partly supported by Amano

Foundation Scholarship. She obtained Ph. D degreeat Nanovision Technology Department, Graduate

School of Science and Technology, Shizuoka University under the

supervision of Prof. Masaaki Nagatsu. Her research interests are inorganic

and materials chemistry, and surface modication by plasma processing.

Shun Tsumurareceived the B.S. and M.S. degrees in electrical engineering

from Shizuoka University in 2011 and 2013, respectively. During his

bachelor and maste r cour ses, he engaged in the study of su rface modication

of magnetic nanoparticles by using an RF excited inductively coupled

plasma under the supervision of Prof. Masaaki Nagatsu.

Masaaki Nagatsu received the B.S., M.S., and Dr.

Eng. Degrees from Nagoya University in 1975,

1979, and 1985, respectively. During 1975 to 1976,he worked for Hitachi Research Laboratory, Hitachi,

Ltd. From 1982 to 2000, he was an assistant

professor (19821989), lecturer (19901991), and

associate professor (19912000) in the Department

of Electrical Engineering of Nagoya University.

During 19871989, he worked as a visiting

researcher in University of California, Los Angeles.

In 2001, he became a professor of Department of Engineering in Shizuoka

University. He became a Director of Graduate School of Science and

Technology, Research Division in 2006 and a Dean of Graduate School of

Science and Technology of Shizuoka University since 2008. His research

eld is the plasma production and surface modication of materials for bio-

medical and environmental application.



surface modification by plasma

Documents