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We report an interfacial approach for fabricating coordination polymer (CP) crystal films and patterns on a polymer surface using a metal ion-doped polymer substrate.

The interaction between negatively charged all-inorganic silicon quantum dots (Si QDs) and bovine serum albumin (BSA) is studied. It is shown that a small difference in the size of Si QDs affects the structure of Si QD–BSA composites significantly. When the diameter of Si QDs is 4 nm, a heterodimer (~20 nm) composed of one Si QD and one BSA molecule is a preferable and stable structure. On the other hand, when the diameter is 7 nm, the size of the composites increases to ~50 nm. The Si QD–BSA composites exhibit stable photoluminescence in the near-infrared range in phosphate-buffered saline.

A simple composition control route to mixed-lanthanide metal-organic frameworks (MOFs) was developed based on an interfacial reaction with mixed-lanthanide metal ion-doped polymer substrates. By controlling the composition of lanthanide ion (Eu3+ and Tb3+) dopants in polymer substrates to be used as metal ion precursors and scaffolding for the formation of MOFs, [EuxTb2−x(bdc)3(H2O)4]n crystals with a tunable metal composition could be routinely prepared on polymer substrates. Inductively coupled plasma (ICP) measurements revealed that the composition of the obtained frameworks was almost the same as that of the initial polymer substrates. In addition, the resulting [EuxTb2−x(bdc)3(H2O)4]n crystals showed strong phosphorescence because of Eu3+ transitions, indicating that the energy transfer from Tb3+ to Eu3+ ions in the frameworks could be achieved with high efficiency.

The widespread demand of coating, corrosion protection, metallurgy, and microelectronics industries for electrodeposition has been met by developing current successful, commercially-available deposition baths containing metallic salts at higher concentration, highly concentrated supporting electrolytes, and various kinds of organic additives, enabling higher deposition rate, greater current efficiency, and long-term stability for the baths. However, developing effective deposition systems for high-performance electrodeposition is challenging, because, (1) in product point of view, the additives sometimes and rather often cause mechanical and/or electrical problems for deposited metal circuit elements due to inclusion of such additives during deposition process, and, (2) in processing point of view, commercial electrodeposition setups cause huge amount of detrimental effluents that can be a serious environmental and cost problems. These issues may be a product of compromise that is particularly relevant for structure and properties of the deposited metals (film resistivity, surface roughness, mechanical and adhesion strength), and processing (costs and manufacturing steps including rinsing and detrimental effluents treatment). The current solution-based electrodeposition systems are generally incapable of significantly increasing reaction rate (deposition rate constant) form dilute electrolyte solution, because diffusion-limiting current that needs to be higher for industrial manufacturing depends on the concentration (and its gradient) of electrolyte solution, which can be described by Fick’s first law in a steady-state electrodeposition. Additionally, current electrodeposition systems are optimized for large area substrate and mass production manufacturing, thereby cannot be suitable for small-lot, on-demand, and multi-product microfabrication. These have inspired the use of polyelectrolyte membranes to encapsulate metallic ions within inside their channels to concentrate from electrolyte solution while maintaining efficient ion transport properties owing to high density anionic counterparts inside channels and the swelling nature of the membrane.We now show that when the polyelectrolyte membrane does not anchor itself to the cathode substrate, stable electrodeposition of metals on cathode surface is achieved, not as much like a solution-phase electrodeposition, resulting in a new type of solid-state electrodeposition (SED) system (Fig. 1). The SED system consists of cathode electrode, polyelectrolyte membrane (PE), electrolyte solution, and anode electrode.PE works as an additional interfacial phase, in which metal ions are transferred through ion exchange reaction based on concentration gradient of metal ions bound with sulfonic acid functional groups in PE layer. Most important feature of the use of PE at the electrode surface is their ability for metal ions to be concentrated in inner ion transport channels with high density sulfonic anions inside the channels (Fig.1). In the current contribution, we describe transfer process of copper ions between electrodes where the additional PE-solution interfacial layer has been introduced to explain concentration behavior of PE layer for copper ions and electrodeposition characteristics in the present system. From detailed theoretical (both thermodynamic and kinetic) and experimental study regarding with the ion concentration process for PE membrane suggest that (1) the “ion penetration” process is slower than ion exchange (diffusion) process inside PE layer and is therefore rate-determining step for ion concentration, and (2) ion penetration rate increases exponentially as the concentration of copper ions in PE layer decreases.The effect of cation concentration, temperature, and electrochemical deposition conditions on the current efficiency, deposition rate, growth process and morphology of the films has been investigated to optimize the deposition conditions to achieve higher deposition rate. This strategy can be suitable for small-lot, on-demand, and multi-product microfabrication. Figure 1

Nickel-nanoparticle-containing polyimide composite films were prepared by liquid-phase reduction of Ni2+ ions with potassium borohydride (KBH4). The nanoparticles were amorphous with diameters of approximately 10–20 nm, depending on the KBH4 concentration and reduction temperature. At high KBH4 concentrations, the nanoparticles appeared to contain various nickel boride species. The number of nanoparticles and Ni content both increased upon repeated adsorption/reduction of Ni2+ ions, where the particle growth was inhibited by the rigid polymer chain and the formation of smaller particles was favored.

We report a unique method for the site-selective growth of metal–organic frameworks (MOFs). The site-selective growth of MOFs can be achieved by fabricating a pattern of polymer photoresist on the metal-ion-doped polymer substrate and then constructing frameworks by immersion in an organic ligand solution.

In situ formation of Cu–Ni alloy nanoparticles with controlled composition in thin polyimide layers was investigated. The ferromagnetic properties of the nanoparticles were found to depend on the composition and the interparticle distance between the nanoparticles.

Aberrant activation of RAS signalling pathways contributes to aggressive phenotypes of cancer cells. The RAS-targeted therapies for cancer, therefore, have been recognised to be effective; however, current developments on targeting RAS have not advanced due to structural features of the RAS protein. Here, we show that expression of NRAS, a major isoform of RAS, can be controlled by photo-irradiation with an anionic phthalocyanine, ZnAPC, targeting NRAS mRNA. In vitro experiments reveal that ZnAPC binds to a G-quadruplex–forming oligonucleotide derived from the 5′-untranslated region of NRAS mRNA even in the presence of excess double-stranded RNA, which is abundant in cells, resulting in selective cleavage of the target RNA’s G-quadruplex upon photo-irradiation. In line with these results, upon photo-irradiation, ZnAPC decreases NRAS mRNA and NRAS expression and thus viability of cancer cells. These results indicate that ZnAPC may be a prominent photosensitiser for a molecularly targeted photodynamic therapy for cancer., Hyperactivity of the gene NRAS contributes to the proliferation and metastatic nature of many types of cancer cells. Here, the authors show that NRAS can be controlled by an anionic phthalocyanine coordinating Zn2+ in combination with photo-irradiation.

Near-monodisperse, micrometer-sized polypyrrole-palladium (PPy-Pd) nanocomposite-coated polystyrene (PS) particles have been coated with Ni overlayers by electroless plating in aqueous media. Good control of the Ni loading was achieved for 1.0 μm diameter PPy-Pd nanocomposite-coated PS particles and particles of up to 20 μm in diameter could also be efficiently coated with the Ni. Laser diffraction particle size analysis studies of dilute aqueous suspensions indicated that an additional water-soluble colloidal stabilizer, poly(N-vinyl pyrrolidone), in the electroless plating reaction media was crucial to obtain colloidally stable Ni-coated composite particles. Elemental microanalysis indicated that the Ni loading could be controlled between 61 and 78 wt% for the 1.0 μm-sized particles. Scanning/transmission electron microscopy studies revealed that the particle surface had a flaked morphology after Ni coating. Spherical capsules were obtained after extraction of the PS component from the Ni-coated composite particles, which indicated that the shell became rigid after Ni coating. X-ray diffraction confirmed the production of elemental Ni and X-ray photoelectron spectroscopy studies indicated the existence of elemental Ni on the surface of the composite particles.

Silica hemispheres containing gold nanoparticle cores have been synthesized via immobilization of gold nanoparticles on a substrate and site-selective growth of silica followed by removal of the hemispherical particles. The structure of these asymmetric heteronanoparticles allows selective etching or overgrowth of the core gold seeds, which results in the respective formation of hemispherical capsules or gold homodimers.

Demand for the development of deposition strategies of well-defined metal thin films with good chemical and physical characteristics has been rapidly growing in the field of various electronics applications. The conventional plating bath for electro- or electroless copper deposition involves various chemical reagents such as deposition promoter (or inhibiter), brightening and smoothing agent, etc. These additives, typically organic molecules, sometimes cause mechanical problems due to inclusion of such additives during deposition process, and the discharge from the deposition bath can be a serious environmental issue. Therefore, the development of a facile process that enables additive-free deposition of metallic thin films as well as low environmental toxicity is an important challenge for the fabrication of next generation microelectronic elements. In this context, herein we report that metallic thin films can be deposited through polyelectrolyte thin layers placed on the cathode electrode by the diffusion of metallic ions from the interior of polyelectrolyte, which is essentially different to conventional solution-phase electrodeposition processes (Figure 1). As a proof of concept study, we present the successful electrochemical deposition of copper thin films at the interface between an electrode and ion-doped polyelectrolyte layers from the baths containing only metal salts (without any additives). In the case for the present three-phase electrochemical system consisting of cathode electrode, polyelectrolyte membrane (PE), and electrolyte solution, PE works as an additional interfacial phase, in which metal ions are transferred through ion exchange reaction based on concentration gradient of metal ions bound with sulfonic acid functional groups in PE layer. Most important feature of the use of PE at the electrode surface is their ability for metal ions to be concentrated in inner ion transport channels with high density sulfonic anions inside the channels. In this electrochemical system, reduction of metal ions to form metal atoms (thus metal films) occurs at electrode-PE interface, and ion exchange reaction occurs inside PE and also at the interface between PE and electrolyte solution. Specific characteristics for the present three-phase electrochemical deposition system can be described as follows. In the case that the deposition rate of metals is below maximum ion exchange rate for PE, (1) concentration of metal ions in PE phase remain unchanged due to higher ion exchange rate than deposition rate in this condition, thus enabling constant current and deposition rate during electroplating, and (2) ion transport number is nearly unity in PE phase because sulfonic anions in PE layer can form metal salts in this condition, i.e., there are mostly no protons to be reduced to form hydrogen bubble, where higher current efficiency for metal deposition can be guaranteed. In the current contribution, the effect of cation concentration, temperature, and electrochemical deposition conditions on the current efficiency, deposition rate, growth process and morphology of the films has been investigated. Several electrochemical, microscopic and quantitative analysis revealed that the metallic films have been successfully deposited at the cathode-polyelectrolyte interface, the deposition rate of which are substantially determined by ion exchange rate of cations. This strategy offers an opportunity to translate solution-phase electrochemical deposition into an on-demand, high-throughput, cost-effective, and environmentally-friendly process for the fabrication of microelectronics circuit elements. Figure 1

We describe the use of ion-exchangeable, highly cross-linked polymer films as a matrix for the synthesis of nanocomposite thin films and patterns with embedded Cu and Ni nanoparticles. We have successfully controlled the size of metal nanoparticles and thus optical and magnetic properties of the films by varying the initial amount of doped metal ions.

ガラス基板上に銅微細回路パターンを形成することを目的として，カルボン酸を電子ドナーとする光化学還元法について検討した。銅イオンの光化学還元反応は，UV照射部全面で起こるが，それを水で洗浄するとあらかじめガラス基板上に形成した疎水性のn-octadecyl trimethoxysilaneパターン上にのみ銅析出物が残存した。親水性のガラス表面に析出した銅薄膜は，水のような極性溶媒による洗浄により，選択的にリフトオフされる。析出する銅薄膜の厚さは，UV照射の時間により容易に制御することができる。局部分極曲線の測定の結果，本研究の光化学還元法において混成電位理論が成立することが明らかとなった。

This report describes a new process for ULSI minute copper-wiring formation. It relies on microcontact printing [μCP] of polyethylene glycol bis(1,2,3-benzotriazolylether) [PBTA]—synthesized from polyethylene glycol and benzotriazole—to the surface of copper seed layer, with preferential copper electrodeposition in PBTA-free regions (contact hole and trench) using an acid copper sulfate bath. The copper electrodeposition was done using an insoluble anode in the basic bath without additives. The microcontact printed PBTA on the copper seed-layer surface strongly inhibits copper electrodeposition. Using this process, because of the effect of site-selective printing of PBTA, a minute contact hole can be filled completely with copper without causing voids and seams.

In the basic concept of conventional electroplating, the additives, which determine the properties of the deposited film, are included in the plating bath. In this report, ULSI copper minute wiring formation by a new process is described. The process relies on the pre-adsorption of the polyethylene glycol bis (1, 2, 3-benzotriazolylether) [PBTA] synthesized from polyethylene glycol and benzotriazole, and copper electrodeposition from an acid copper sulfate bath without additives. The copper electrodeposition was done using an insoluble anode in the basic bath without additives after PBTA was pre-adsorbed on the silicon wafer with copper seed. The adsorbed PBTA on the surface of the copper seed strongly inhibited copper electrodeposition. In this process, a minute hole can be filled with copper without causing voids and seams due to the effect of site-selective adsorption of PBTA.

Nanoscale metal particles have been of great interest in the development of next generation micro- and nano-electronics devices. In this review, we describe the characteristics and applications of monolayer-protected metal nanoparticles as well as importance of controlling their surface and interfacial structures for electronics applications, on the basis on our recent experimental results. Recently, much effort has been devoted to directing monolayer-protected metal nanoparticles into organized structures onto solid supports by a variety of fabrication techniques. One of the emerging techniques for immobilization is to use organic monolayers attached on the nanoparticles and substrate of interest to guide the assembly of the nanoparticles through predesigned chemical and physical interactions. We demonstrate a novel technique for the fabrication of two-dimensional microscopic assembly of monolayer-protected gold nanoparticles onto substrates. Selective integration of the nanoparticles onto either hydrophobic or hydrophilic region on the substrates could be achieved by controlling dispersion-aggregation process of gold nanoparticles, thereby providing effective methodology for fabrication of various patterns of integrated mesoscopic nanoparticle assemblies that can be further used for development of metallic circuits. Our next interest is to develop simple strategy for fabrication of metallic circuits on polymeric substrate, with high adhesive strength achieved via novel concept of nanoscale interlocking mediated by metal nanoparticles. We proposed novel process for forming metallic circuit patterns on polyimide substrate, which has excellent electrical, thermal, chemical and dielectric properties. The process involved a surface modification of polyimide, incorporation of metallic ions followed by reduction to form thin films consisting of metal nanoparticles. We have succeeded to fabricate metallic silver and copper circuit patterns that are highly adhesive due to the interlocking mediated by metal nanoparticles at metal/polymer interface. The interfacial structures presented here are promising for future miniatulization of metallic circuit patterns in microelectronic devices.

A study aimed at investigating the process of formation of hybrid nanocomposites consisting of a thin polyimide layer containing copper nanoparticles of varying sizes (3−10 nm in diameter) is described. In this system, precursor layers in which copper ions are fully or modestly doped in a chemically modified polyimide matrix are annealed in a hydrogen atmosphere at a constant heating rate. Reduction behavior of doped copper ions and changes in the chemical structure of the matrix film were characterized by inductively coupled plasma atomic emission spectroscopy and Fourier transform infrared spectroscopy, respectively. The results revealed that there is a strong correlation between both the process of reduction to form copper nanoparticles and the dehydration reaction of the matrix that forms heterocyclic imide rings (re-imidization), depending on the initial loading of copper ions. Transmission electron microscopy coupled with nanobeam energy-dispersive X-ray analysis was utilized to observe that upon an...

Nylon 6 doped with Ag nanoparticles (nylon 6/Ag) was prepared by immersion of nylon 6 in aqueous AgNO3 solution followed by reductive treatment by heating under H2 gas or immersing in an aqueous NaBH4 solution. As a result of either reductions, Ag nanoparticles below 10nm in diameter were successfully dispersed within the nylon 6 matrix. The Ag content and the dispersion state of the Ag nanoparticles can be varied by the concentration of the AgNO3 solutions and the reduction methods, respectively. From the results of the absorbed Ag+ content in nylon 6 via immersion in AgNO3 solution, nylon 6 was found to have some affinity for silver ion. Nylon 6 doped with Ag2S nanoparticles (nylon 6/Ag2S) was also prepared by immersion in AgNO3 aqueous solution and the following immersion of Na2S aqueous solution. Ag2S particles having several nanometers in diameter were dispersed in nylon 6. The nylon 6/Ag2S film showed strong photoluminescence in the near infrared region.

スズ-亜鉛共晶合金は, 融点が現行のスズ-鉛共晶合金のそれに近いことから, 鉛フリーはんだの候補として期待されている。ポリオキシエチレン-α-ナフトール (POEN) を添加剤とするスルホコハク酸浴から, カソード電流密度0.5～3A/dm2において, 共晶組成 (亜鉛9mass%) を有する合金皮膜が得られた。POENの添加は, スズ析出の分極を増大し, 低電流密度領域におけるスズの優先析出を抑制することにより, 亜鉛の共析を可能にした。めっき浴は極めて安定であり, 6カ月経過後においてもSn4+化合物の沈殿形成は認められなかった。スズ-亜鉛共晶合金皮膜は, β-スズ相と亜鉛相からなり, その融点は198℃であった。銅素地上のスズ-亜鉛共晶合金皮膜には, 1年間の室温経時後においてもウイスカの発生は認められなかった。

The formation of LSI copper minute wiring by the electroless plating process is expected to become a dominant process for LSI interconnection because of the advantages in obtaining a film of uniform thickness on a dielectric film. Moreover, there is a possible application in three-dimensional wiring and three-dimensional mounting, which use the ball chip technology. However, the conformal deposition of metal basically takes place in electroless plating. The copper electroless deposition was done using neutral electroless plating after the copper seed layer of the sillicon wafer surface had pre-adsorbed PEG 4000 under the condition of coexistence with chloride ions. In the method utilizing pre-adsorption, a minute contacthole can be filled with copper without causing a seam due to the effect of the pre-adsorbed additive. The copper film obtained from this process is advantageous in electromigration (EM) resistance, because the priority orientation the (111) plane, which is the close-packed plane of the fcc structure, is shown and the crystallite size is 37nm. The specific resistance of the copper film is 1.85μΩ·cm.

In the basic concept of conventional electroplating, the additive, which determines the properties of the de-posited film, is included in the bath. However, it is difficult to solve the problems related to copper minute wiring as long as one clings to this concept. In this report, ULSI copper minute wiring formation by a new process, which consists of the pre-adsorption of the additive and copper electrodeposition from an acid copper sulfate bath without an additive, will be described. A copper layer of 1μum thickness was deposited from a basic bath on the copper electrode on which the additive had been pre-adsorbed, and the catholic polarization in the basic bath which does not contain an additive was then measured. The continuance of the efficacy of the additiveafter the copper electrodeposition was confirmed. The copper electrodeposition was done using an insoluble anode in the basic bath without an additive after the silicon wafer which formed the copper seed had pre-adsorbed the additive. In the method utilizing pre-adsorption., a minute hole can be filled with copper without causing voids and seams due to the effect of the pre-adsorbed additive.

Sn-Cu-Ag合金めっきは, Sn-Pbはんだめっきの代替として有望であり, 優れた耐熱疲労特性を有している。トリスー3ーヒドロキシプロピルホスフイン (T3HPP) , ポリオキシエチレンーαーナフトール (POEN) および2, 2, -ジチオジァニリン (DTDA) を添加剤とするメタンスルホン酸浴から, 電流密度0.5～5A/dm2において, 目的組成Sn-0.7Cu-0.3Ag (組成: mass%) の合金皮膜が得られた。T3HPPの添加は, 浴の安定性を著しく改善した。この合金皮膜は, β-Sn相とCu6Sn5相およびAg3Sn相からなり, その融点はほぼ225℃の値を示した。銅素地上のSn-0.7Cu-0.3Ag合金皮膜には, 6カ月の室温経時後においてもウイスカの発生は認められなかった。

Conventional electrodeposition process is widely used for various kinds of functional parts such as electronics, anti-corrosion, decoration and so on. However, this process has serious problem due to a large quantity of waste fluid including toxic substance. Recently, environmental regulation has been strengthened, so that the production line may be needed to be closed system for recycling the waste fluids. Moreover, the additionl processes such as masking and etching is indispensable in producing the patterned circuit board, leading to high cost for final products. We have developed the novel electrodeposition process to solve the environmental and cost problems of a conventional electrodeposition. As shown in Fig. 1, the novel deposition system is simply composed of electrodes, metal solution and polyelectrolyte. By applying potential between two electrodes, metal films are deposited at solid-solid interface, i.e., cathode electrode and polyelectrolyte; electrolyte solution is separated from cathode electrode by polyelectrolyte in which metallic ions can be diffused through ion-exchange reaction. Therefore, when this system is accumulated into small probe system, this process enables electrodeposition of metals only by attaching polyelectrolyte surface into cathode surface in a serial patterning manner, whereas conventional electrodeposition process is based on immersing the substrate of interest into electrolyte solution. We call this novel system, “solid electrodeposition (SED)”. The characteristics of the process are as follows. 1) The system needs only small amount of electrolyte solution, and washing of the cathode substrate after metal deposition is not necessary because of growth of the films at solid-solid interface, leading to much small amount of waste solution. 2) Site-selective deposition can be achieved only by controlling the contact area of the polyelectrolyte used for deposition (Fig. 2a). 3) Since the deposition can proceed through diffusion of metal ions through fine, large amount of ion channels in polyelectrolytes, metal films constructing of tiny crystallites are deposited (Fig. 2b). Electrical resistivity of the copper films deposited by SED process is comparable with that of bulk copper, indicating high purity, well-defined copper films are deposited on the substrates. From these results, this process offers an effective, environmentally friendly methodology for fabricating metal films in atmospheric conditions and can be, therefore, applied for various microelectronic applications. Figure 1

Demand for the development of deposition strategies of well-defined metal thin films with good chemical and physical characteristics has been rapidly growing in the field of various electronics applications. For example, copper electro- or electroless deposition has been widely utilized and investigated in microelectronics industry due to its low electrical resistivity and high electromigration resistance, as compared with aluminum. The conventional plating bath for electro- or electrolless copper deposition involves various chemical reagents such as deposition promoter (or inhibiter), brightening and smoothing agent, etc. These additives, typically organic molecules, sometimes cause mechanical problems due to inclusion of such additives during deposition process, and the discharge from the deposition bath can be a serious environmental issue. Therefore, the development of a facile process that enables additive-free deposition of metallic thin films as well as low environmental toxicity is an important challenge for the fabrication of microelectronic elements. In order to sustain the demand for generating multichip packaging systems for future electronic devices, it would be exceedingly useful to develop novel electrochemical deposition strategy with high-throughput capability that would allow stability of electrochemical reaction at higher deposition rate from plating bath without organic additives. In this context, direct metal deposition processes though ion conducting films have been investigated, such as the fabrication of metallic patterns on polymer substrates using ion-doped precursor films. A variety of direct deposition techniques have been introduced by several groups, including ours,1,2) based on photoinduced chemistry, thermal treatment, and selective chemical reduction for polyimide and other functional polymers. We have also reported a chemical metallization strategy that utilizes electrochemical constructive lithography with post lift-off process, which enables the fabrication of metal patterns on the polyimide substrate.3) The use of ion-doped precursors has triggered the development of new concept for electrochemical deposition. Herein we report for the first time that metallic thin films can be deposited through polyelectrolyte thin layers placed on the cathode electrode by the diffusion of metallic ions from the interior of polyelectrolyte, which is essentially different to conventional solution-phase electrodeposition processes (Fig. 1). By taking advantage of the cation-exchangeable nature of polyelectrolyte layers used for creation of solid interface, we demonstrate in this study how it is possible to merge the electrochemical deposition at cathode-polyelectrolyte interface and diffusion of cations through polyelectrolytes for development of novel solid electrodeposition (SED) process. As a proof of concept study, we herein present the successful electrochemical deposition of copper and nickel thin films at the interface between an electrode and ion-doped polyelectrolyte layers from the baths containing only metal salts (without any additives). The effect of cation concentration, temperature, and electrochemical deposition conditions on the deposition rate, growth process and morphology of the films has been investigated. Several electrochemical, microscopic and quantitative analysis revealed that the metallic films have been successfully deposited at the cathode-polyelectrolyte interface through ion exchange reaction in the polyelectrolyte layers, the deposition rate of which are determined by ion exchange rate of cations. This strategy offers an opportunity to translate solution-phase electrochemical deposition into a high-throughput, cost-effective, environmentally-friendly process for the fabrication of metal thin films on substrates. 1) Matsumura, Y. Enomoto, T. Tsuruoka, K. Akamatsu, H. Nawafune, Langmuir, 26, 12448-12454 (2010). 2) S. Ikeda, H. Yanagimoto, K. Akamatsu, H. Nawafune, Adv. Funct. Mater., 17, 889-897 (2007). 3) K. Akamatsu, Y. Fukumoto, T. Taniyama, T. Tsuruoka, H. Yanagimoto, H. Nawafune, Langmuir, 27, 11761-11766 (2011). Figure 1