Wettability-patterned Surfaces Research Articles

Enhanced boiling heat transfer performance on wettability-patterned surface

As an efficient heat transfer method, boiling heat transfer (BHT) plays an important role in strengthening the thermal management of high-power electronics, etc. In this work, the wettability patterns are prepared on copper substrate by mask-assisted chemical processing method, which enhances the BHT performance. We firstly treat the copper surface into superhydrophilic by chemical immersion, and then it is modified by fluorosilane into superhydrophobic, and wettability patterns are formed with the assistance of mask. Then, the BHT performances and the corresponding bubble dynamics of the wettability-patterned surfaces are experimentally investigated. Finally, the optimal BHT performances of the wettability-patterned surface prepared by the proposed method are compared with other modified surfaces. The results show that the BHT is improved dramatically on the wettability-patterned surface, the critical heat flux (CHF) and the heat transfer coefficient (HTC) improve by 23% and 56%, respectively. Under high heat flux, the decrease of hydrophobic pattern size can significantly improve the BHT performances, while under low heat flux, reducing the hydrophobic pattern pitch can improve the BHT performances to a certain extent. The reduction of the hydrophobic area has a significant effect on the CHF and HTC.

Freezing propagation between condensed droplets: Visualization and formulation of governing equation from ice bridge growth velocity

Condensation frosting causes performance degradation and other problems in various fields, such as wind power generation and heat exchangers. During the initial stage of condensation frosting, freezing propagation from frozen to supercooled water droplets is often observed, the dynamics of which must be clarified to solve these problems. A frozen droplet forms a protrusion to an adjacent supercooled droplet, known as an ice bridge; the growth velocity of the ice bridge is essential for discussing freezing propagation. In this study, we fabricated wettability-patterned surfaces on silicon wafers to obtain droplets with controlled spacing and size and visualized and evaluated the ice bridge formation process under reproducible conditions, and the local velocity change in the ice bridge growth was measured for the first time. Experiments showed the local velocity of the ice bridge growth increased as the tip of the ice bridge approached the adjacent supercooled droplet. Simple model equations for the freezing propagation velocity and ice bridge growth were proposed. The proposed model agreed well with the measured velocity and did not include any fitting or geometric parameters of the ice bridge or droplets, such as volume or shape.

Nanosecond laser textured superhydrophobic/superhydrophilic patterned surface for efficient fog harvesting

Fresh water shortage is considered as growing global problem due to increasing climate crisis in recent years. Fog harvesting is identified as one of the most sustainable means of freshwater collection. Wettability-patterned surfaces are recognized to have a great potential for fog harvesting. In this work, patterned superhydrophobic/superhydrophilic surface has been fabricated directly on aluminum alloy AA6061 via a nanosecond laser texturing. The superhydrophobic region contains low-roughness, isotropic, random nanostructures whereas the superhydrophilic regions contains highly structured porous microchannels. The fabricated AA6061 surface demonstrated ∼72% enhanced fog harvesting capability compared to the untreated one. Moreover, unlike other fabrication processes, the whole process has more flexibility to create innovative patterns without any requirement of mask.

Efficient fog harvesting on metal surfaces with venation-inspired wetting patterns fabricated via laser-based maskless approach

The issue of global freshwater scarcity has become more pressing as climate change effects intensify. Fog harvesting has emerged as a sustainable and promising solution to address this problem, and wettability-patterned surfaces have shown potential in enhancing fog harvesting efficiency. In this study, two venation-like surface wetting patterns, i.e., the broadleaf and coniferous tree patterns, were directly fabricated on an aluminum alloy (AA6061) using a laser-assisted functionalization method, which offers greater flexibility in creating innovative patterns without the need for a mask. The superhydrophobic region featured low-roughness, isotropic, random nanostructures, while the superhydrophilic regions consisted of highly structured porous microchannels. The resulting surface patterns demonstrated a significant increase of up to 100 % in fog harvesting capability compared to the untreated surface. By adjusting the number of leaves, the fog harvesting efficiency of the venation-like patterns can be further improved while maintaining the same energy investment.

Facile methods for fabricating wettability patterns on metal substrates

Extreme-wettability-patterned surfaces have attracted great attention due to their excellent application prospects for liquid manipulation. However, developing a simple and universal method to fabricate wettability patterns on a variety of metals remains a great challenge. In this work, three specific preparation approaches were developed to fabricate wettability patterns on copper substrates using chemical processing combined with mask technology. Surface wettability can be suitably controlled by changing the solution concentration and immersion time. The surface has good stability and low pollution under external action. The three preparation methods have differences in preparation process, wettability and mask function. On the basis of these approaches, various complex wettability patterns could be prepared on different metal substrates using designed masks. Furthermore, various wettability-patterned surfaces were successfully fabricated for liquid manipulation applications, such as controlling the fluid shape and water transport. The methods proposed are expected to have promising application potential in patternable printing, water collection and heat-dissipation devices.

Influence of hydrophobic area fraction of a wettability-patterned evaporator in an ultrathin vapor chamber

Integrating wettability-patterned surfaces into a multiscale micro/nanostructured evaporator has demonstrated promising thermal performance enhancement of an ultrathin vapor chamber (UTVC). However, the mechanism behind it still remains unknown. To investigate the synergetic effect of wettability-patterned micro/nanostructures on the thermal performance of the UTVC, the hydrophobic area fraction of the wettability-patterned surface in this study varies from 6.25% to 66.9%. The wettability-patterned surface is fabricated on the substrate of the evaporator, and a micro/nanostructured mesh functions as a multiscale wick structure intimately pressed on the wettability-patterned surface to form the evaporator. The total thickness of UTVCs under the investigation is less than 250 µm including the multiscale evaporator, the condenser, and the supporting micropillar array. The thermal performance of UTVCs with different hydrophobic area fractions is evaluated under the optimum charge ratio. To understand the mechanism of the enhancement of wettability-patterned surfaces, a visualization experiment was conducted utilizing a wettability-patterned glass substrate. It is found that the wettability-patterned surface can increase the length of the triple contact line, which enhances the evaporation process. Specifically, the optimum hydrophobic area fraction was found at around 34%. The UTVC with the wettability-patterned surface achieves a maximum 13,820 W/(m·K) in-plane effective thermal conductivity, which is a 162% enhancement compared to the one with a hydrophilic surface. Furthermore, it also provides a 29.1% maximum reduction of vertical thermal resistance of UTVCs. An evaporation model of the wettability-patterned surface integrated with the wire mesh is proposed based on its elongation effect on the triple contact line. The optimum hydrophobic area fraction predicted by the model is 29.9%, which is very close to the experimental results.

Low-profile heat pipe consisting of wick-lined and non-adiabatic wickless wettability-patterned surfaces

Heat pipes are metal-wick equipped systems that circulate a phase-changing liquid and transfer heat more effectively than solid-metal compact heat spreaders. Metal wicks are effective fluid transporters, but they can face capillary limits due to significant pressure drops and pore clogging. Wettability-patterned (WP) surfaces, on the other hand, are not limited by these constraints and, as demonstrated in this work, may offer a viable supplement for metal wicks in heat pipes, which come in many shapes and sizes. The use of WP surfaces facilitates the collection and efficient transport of condensate, thus improving heat transfer from the hot (evaporator) to the cold (condenser) side of the device. Most commonly, flat heat pipes consisting of a fully wick-lined plate opposed to a wickless surface, are evaluated considering a uniform adiabatic condition on the wickless plate, which does not promote condensation. However, in a practical scenario, the heat pipe portions in contact with an external heat sink could induce condensation on the wickless side, thus affecting the heat pipe’s operation and thermal resistance. To explore this scenario, a flat heat pipe of 10 cm operating length with axially graded copper-wick evaporator and non-adiabatic wickless WP surface is designed, fabricated and tested. A wettability pattern is imparted on the wickless surface to control the maximum droplet size of the condensate and condensation mode via spatially designed superhydrophilic/hydrophobic juxtaposed areas to regulate both Dropwise Condensation (DwC) and Filmwise Condensation (FwC) towards enhanced heat transfer with reduced overall system thermal resistance. Low capillary pressure domains are allocated in this design to collect condensate on the wickless plate and return it to the evaporator’s wick. On the evaporator side of the system, variable-porosity copper wicks are being used to improve liquid conveyance from the cold to the hot domains. Four heat-transfer fluid charging ratios are examined with the best thermal resistance 0.27 K/W achieved at 105 W. The effect of wettability patterning on the wickless surface and the wick characteristics of the wick-lined evaporator are investigated. • Low-profile hybrid heat pipe comprised of wick-lined and wickless components. • Three distinct wick structures and wettability patterns investigated and compared. • Axially-graded wick structure outperforms uniform wicks. • Wettability-patterned wickless plate lowers thermal resistance. • Highest-performing system’s thermal resistance below 0.3 K/W.

Rupture of bar-coated liquid films on wettability-patterned surfaces

Rupture of bar-coated liquid films on wettability-patterned surfaces

Enhancement of flow boiling heat transfer using heterogeneous wettability patterned surfaces with varying inter-spacing

This study experimentally investigated the influence of heterogeneous wettability-patterned surfaces with varying inter-spacing on flow boiling heat transfer characteristics. The test surfaces consisted of three fluorooctyltrichlorosilane hydrophobic-patterned array structures having a triangle, inverted triangle, and circular shape on a SiO2- hydrophilic substrate, with an inter-spacing of 0.75 or 1 mm. The working fluid was deionized water, and the Reynolds number was 6,000 at atmospheric pressure. Among the test surfaces, varying the inter-spacing between neighboring hydrophobic patterns slightly enhanced the heat transfer coefficient (HTC) due to changing the bubble characteristics. In terms of the shape effect of hydrophobic patterns, the heterogeneous wettability-patterned surfaces dominated the overall flow boiling heat transfer performance showing a significant increase in critical heat flux (CHF) compared to the Si surface, by 40–43%. In addition, all of the wettability test surfaces showed a markedly higher heat transfer coefficient than the Si surface, by 35–163%. This experiment is explained by analyzing the relationship between bubble lift forces and the various hydrophobic-patterned shapes in a horizontal flow channel, in an attempt to better understand flow boiling heat transfer and optimize the pattern design.

Pattern geometry optimization on superbiphilic aluminum surfaces for enhanced pool boiling heat transfer

In this study, the optimal surface pattern of low and high wettability regions for enhanced boiling heat transfer is investigated using aluminum superbiphilic surfaces. Samples are fabricated by combining chemical vapor deposition of a fluorinated silane to turn them superhydrophobic and nanosecond laser texturing to render selected areas superhydrophilic. Triangular lattice pattern of superhydrophobic circular spots is utilized with spot diameters between 0.25 mm and 1.0 mm and pitch values of 0.5–2.5 mm. Pool boiling heat transfer performance of superbiphilic surfaces is evaluated using saturated water at atmospheric pressure. A strong wettability contrast is shown to be important in ensuring high heat transfer performance of wettability-patterned surfaces. Highest heat transfer performance is achieved using 0.5 mm diameter spots with a spot pitch of 1 mm and a corresponding superhydrophobic area fraction of approx. 23%. The optimal pitch value will provide a high density of potentially active nucleation sites but still allow for the development of the thermal boundary layer thus not inhibiting the activation of neighboring spots. The size of (super)hydrophobic spots appears not to have a major influence on the boiling performance when using the optimal spot pitch. The developed superbiphilic surfaces increase the CHF and provide greatly enhanced heat transfer coefficients especially at medium and high heat fluxes, making them suitable especially for high-heat-flux applications.

Numerical simulation of droplet impact on wettability-patterned surfaces

Numerical simulations have unexplored potential in the study of droplet impact on nonuniform wettability surfaces. In this paper, we compare numerical and experimental results to investigate the application potential of a volume-of-fluid method utilized in OpenFOAM. The approach implements the Kistler model for the dynamic contact angle of impacting droplets. We begin with an investigation into the influence of the most important solver parameters to optimize the computational setup and reach the best compromise between computational cost and solution errors, as assessed in comparison to experimental results. Next, we verify the accuracy of the predictions for droplet impact on uniformly hydrophilic or superhydrophobic surfaces. Benchmarking the maximal spreading factor, contact, and spreading times, as well as contact-line behavior, we show strong agreement between the present numerical results and the models of Pasandideh-Fard et al., Phys. Fluids 8, 650 (1996) and Clanet et al., J. Fluid Mech. 517, 199 (2004). Lastly, we demonstrate the capability of the model to accurately predict outcome behaviors of droplets striking distributed-wettability surfaces, which introduce 3D outcome characteristics, even in orthogonal impact. The model successfully predicts droplet splitting and vectoring, as reported in the experiments of Schutzius et al., Sci. Rep. 4, 7029 (2014). Finally, we demonstrate a configuration wherein a droplet centrally strikes a circular disk of different wettability than its surrounding domain. The main contribution of the present paper is a numerical model capable of accurately simulating droplet impact on spatially nonuniform wettability patterns of any foreseeable design.

Dynamic wetting and heat transfer during droplet impact on bi-phobic wettability-patterned surfaces

This paper reports the dynamic wetting behavior and heat transfer characteristics for impinging droplets on heated bi-phobic surfaces (superhydrophobic matrix with hydrophobic spots). A non-patterned superhydrophobic and a sticky hydrophobic surface acted as control wettability surfaces. As expected, differences in wetting and heat transfer dynamics were noticeable for all surfaces with the most pronounced variation during the receding phase. During spreading, inertia from the impact dominated the droplet dynamics, and heat transfer was dominated by convection at the contact line and internal flow. As contact line velocities decreased over time, evaporative cooling at the contact line gained importance, especially for the bi-phobic surfaces, where liquid remained trapped on the hydrophobic spots during receding. These satellite droplets increased the contact area and contact line length and assisted heat transfer and substrate cooling after lift-off of the main droplet. Compared with the hydrophobic surface, the contribution of the contact line heat transfer increased by 17%–27% on the bi-phobic surfaces depending on the location of impact relative to the hydrophobic spots. Nonetheless, the bi-phobic surfaces had a lower total thermal energy transfer. However, compared with the plain superhydrophobic surface, heat transfer was enhanced by 33%–46% by patterning the surface. Depending on the application, a trade-off exists between the different surfaces: the sticky hydrophobic surface provides the best cooling efficiency yet is prone to flooding, whereas the superhydrophobic surface repels the liquid but has poor cooling efficiency. The bi-phobic surfaces provide a middle path with reasonable cooling effectiveness and low flooding probability.

Experimental investigation of a vapor chamber featuring wettability-patterned surfaces

Vapor-chamber heat spreaders are hermetically-sealed systems that rely on metal wicks to circulate a phase-changing liquid and spread heat more efficiently than solid-metal heat sinks. But metal wicks also impose capillary limitations due to their high pressure drop. Surface-wettability patterning does not pose the same limitations and, as shown in this work, could replace metal wicks in vapor chambers to transport the condensate faster and more efficiently. Combining the fast condensate transport characteristic of wettability patterning with the added advantage of domain-regulated dropwise condensation (DWC) and filmwise condensation (FWC) towards enhanced condensation performance, an intriguing hypothesis is explored here by incorporating surface-wettability patterning inside vapor chambers made of copper with and without wicking posts. Wettability patterns with different ratios of superhydrophilic (FWC-promoting) to hydrophobic (DWC-promoting) domains are explored and compared with a control case of unpatterned mirror-finish copper, all located on the condenser side. The heat-spreading capability of the devices from a heated spot of ~0.9 cm2 to an effective vapor chamber area of ~25.8 cm2 is tested at a horizontal orientation where gravity acts perpendicular to the vapor chamber plane and at a vertical orientation. The lowest thermal resistance achieved is 0.24 K/W at 87 W heat load (heat flux of 97 W/cm2) with a horizontally-placed vapor chamber that has a 0.5 mm-thick evaporator wick, a wettability-patterned condenser plate and no wicking posts. The work offers quantitative arguments for incorporating wettability patterning in vapor-chamber technology, and motivates further optimization towards achieving the full potential of this approach.

Deterioration of boiling heat transfer on biphilic surfaces under very low pressures

Surface wettability engineering has attracted growing attention in recent years as an effective tool to enhance boiling heat transfer. On wettability-patterned (so-called biphilic) surfaces in particular, subatmospheric boiling has been shown to be nearly free of the severe degradation of heat transfer rate that tends otherwise to prevail on plain surfaces. The surprisingly consistent performance under reduced-pressure conditions can be attributed to the rather strong pinning of the three-phase contact line (TPCL) at the border between the hydrophobic and hydrophilic surfaces, which essentially eliminates the waiting period between bubble cycles. Only when the pressure is decreased sufficiently low does the transition to the undesired mode of intermittent boiling eventually occur on the biphilic surface. The purpose of the present study is to investigate the physical mechanism for the heat transfer deterioration on a mixed-wettability surface at very low pressures. To that end, we performed high-speed visualization experiments of the process of bubble nucleation and growth on a smooth copper surface coated with a single hydrophobic polytetrafluoroethylene (PTFE) spot, under different surface superheats and system pressures. The results show an interesting correlation between the TPCL behavior and the bubble growth dynamics. Specifically, under some certain threshold of pressure, it would become increasingly likely for the TPCL to be dislodged from its pinned position on the biphilic surface under a particularly rapid bubble expansion. As a result, full flooding of the hydrophobic surface might ensue, which is deemed responsible for temporary deactivation of the hydrophobic spot as a viable nucleation site. Furthermore, based on the diffuse-interface simulations of TPCL propagation across heterogeneous wettabilities, a comparison of cases with different bubble expansion rates offered qualitative evidence supporting the critical role of such accelerated bubble growth rate in driving the TPCL to overcome the energy barrier raised at the wettability divide.

Rapid Prototyping of an Open-Surface Microfluidic Platform Using Wettability-Patterned Surfaces Prepared by an Atmospheric-Pressure Plasma Jet.

Open-surface microfluidics is promising in terms of enabling economical and rapid biochemical analysis for addressing challenges associated with medical diagnosis and food safety. To this end, we present a simple and economical approach to develop an open-surface microfluidic platform suitable for facile liquid transport and mixing. Customizable patterns with tailored wettability are deposited using a plasma-assisted deposition technique under atmospheric pressure. The flow of the dispensed liquid is driven by gravity, and the tilting angle of the device determines the extent of mixing. First, a hexamethyldisiloxane film was deposited to create hydrophobic patterns on glass, and then, hydrophilic acrylic acid was deposited by a patterned cardboard mask to construct a channel suitable for forming channels to transport aqueous liquids without the need of an external energy input; the liquid can be confined to designated pathways. Several designs including Y-junctions, serpentine-shaped patterns, splitting channels, and concentration gradient generation patterns are presented. The proposed method can spatially pattern a surface with a hydrophobic/hydrophilic area, which can function as a microfluidic channel, and the surface can be applied in microfluidic devices with other types of substrates.

Superhydrophilic–superhydrophobic patterned surfaces on glass substrate for water harvesting

Directional water harvesting is a special ability of flora and fauna in nature. Wettability-patterned surfaces inspired by natural structures have been extensively researched and could be a great potential avenue for easing water shortage. However, preparation strategies for these nature-inspired cases, including UV irradiation with mask technology, femtosecond laser direct writing and chemical treatment, are time-consuming, cost-ineffective and environmentally unfriendly. In this paper, robust and durable superhydrophobic (SHB) glass substrate was prepared by using laser-induced backward transfer technique and fluoroalkylsilane modification. Then wedge-shaped superhydrophilic (SHL) patterns on the SHB surfaces were rapidly constructed by inexpensive and commercially available fibre laser ablation for fog harvesting. This facile, cost-effective and non-corrosive preparation method described herein could be an alternative way to construct SHL–SHB patterns on glass substrate, which could be used for microfluidic devices, droplet manipulation and cell screening.

Enhanced pool boiling of ethanol on wettability-patterned surfaces

Due to the considerably reduced boiling point, organic fluids such as ethanol provide an attractive alternative to water as the working fluid in two-phase thermal management systems for high-heat-flux applications. The state-of-the-art enhancement methods for ethanol boiling normally involve surface structure engineering. Here we report, for the first time, enhancement of nucleate boiling of ethanol using wettability-patterned surfaces. By depositing onto a polished copper surface an array of circular spots of superamphiphobic coating of modified halloysite nanotubes (HNT) with fluoropolymer, which was shown to repel low-surface-tension fluids, we managed to create a meaningful biphilic pattern of alternating hydrophobicity (with ethanol contact angle exceeding 100°) and hydrophilicity (with contact angle close to 0°) on the surface. Boiling heat transfer was found to be improved dramatically on the coated surface. Specifically, the onset of nucleate boiling was found to drop by more than 35%. Moreover, at 20 K surface superheat (above the boiling point), a maximum heat transfer enhancement over 300% compared with a plain copper surface occurred on the surface with a pitch-to-spot ratio close to 2.5. The significantly increased heat transfer rate of the biphilic surfaces could be attributed to facilitated bubble nucleation and stronger agitation effect.

Uphill Water Transport on a Wettability-Patterned Surface: Experimental and Theoretical Results.

In nature, there exist many functional water-controlling surfaces, such as the water-repellent surface of lotus leaves, the superhydrophobic water-adhesive surface of rose petals, the water-harvesting surface of a beetle's back, and the water-transporting surface of the legs of Ligia exotica. These natural surfaces suggest that surface chemistry and hierarchical structures are essential for controlling the water behavior. We have reported the preparation of superhydrophobic and antireflection silicon nanospike-array structures using self-organized honeycomb-patterned films as three-dimensional dry-etching masks. Moreover, the surface wettability of the silicon nanospike-array structures can be easily transformed from superhydrophobic to superhydrophilic by changes in the surface chemistry. In this report, we show the preparation of water-controlling surfaces, such as water-harvesting and water-transporting surfaces, by the wettability patterning of silicon nanostructured surfaces. We prepared honeycomb-patterned films for dry-etching masks made from polystyrene and an amphiphilic polymer by casting a chloroform solution. After the fixation of the top layer of the honeycomb-patterned films on a single-crystal silicon substrate, reactive ion etching was performed. The as-prepared silicon nanospike-array structure showed superhydrophobicity, and the water contact angles were over 170°. After UV-O3 treatment with photomasks, only the UV-irradiated surfaces showed superhydrophilicity, suggesting that we can obtain superhydrophobic- and superhydrophilic-patterned surfaces for which the patterns are the same as those of the photomasks. On the basis of these wettability-patterned surfaces, we demonstrated water harvesting by superhydrophilic dot-patterned surfaces and water transportation against gravity by superhydrophilic triangular-patterned surfaces. In particular, we investigated uphill water transport through the motion of droplets on tilting slopes based on the equation of motion. These results suggested that we can obtain superior microfluidic devices suitable for various applications through the use of optional wettability patterns.

Calcination-free micropatterning of rare-earth-ion-doped nanoparticle films on wettability-patterned surfaces of plastic sheets

We demonstrate a patterning technique of rare-earth-ion-doped (RE) nanoparticle films directly on wettability-patterned surfaces fabricated on plastic sheets in one step. Self-assembled monolayers consisting of silane-coupling agent with hydrophobic groups were fabricated on plastic sheets. UV–ozone treatments were performed through a metal mask to selectively remove the self-assembled monolayers in a patterned manner, resulting in the formation of wettability-patterned surfaces on plastic sheets. Using a water dispersion of Er3+ and Yb3+-codoped Y2O3 nanoparticles at a diameter of 100nm, RE-nanoparticle films were fabricated on the wettability-patterned surfaces by a dip-coating technique. By adjusting the concentration of RE-nanoparticle dispersion, withdrawal speed, and withdrawal angle, amount of RE-nanoparticles, we were able to control the structures of the RE-nanoparticle films. Fluorescence microscope observations demonstrate that visible upconversion luminescence and near-infrared fluorescence were emitted from the RE-nanoparticle films on the wettability-patterned surfaces. This technique allows for the fabrication of flexible emitting devices with long-operating life time with minimized material consumption and few fabrication steps, and for the application to sensors, emitting devices, and displays in electronics, photonics, and bionics in the future.

Micropatterning of functional dye films on wettability-patterned surfaces using soft liquid-phase adsorption

We discuss a “soft” liquid-phase adsorption (SLPA) technique to control formation of organic dye films on wettability-patterned templates by using methanol/hexane emulsions. Wettability-patterned templates were fabricated by the formation of self-assembled monolayers of silane-coupling agents on glass plates followed by UV-ozone treatment through a metal mask. Rhodamine B and thymol blue films were formed selectively on the hydrophilic regions of the wettability-patterned templates. The thickness of the rhodamine B films increased with a decrease in immersion temperature and with an increase in immersion angle of the wettability-patterned templates in the emulsions. The thickness of the thymol blue films was significantly larger than that of the films fabricated by conventional film-forming techniques such as spin-coating and dip-coating. The thymol blue films served as pH-responsive devices under exposure to HCl and NH3 gasses. The SLPA technique allows for the fabrication of organic thin films on wettability-patterned templates with little material consumption and a few film-forming processes, contributing to application to the fabrication of organic photonics and electronics devices with reduction of environmental burdens.