Utilization of Resist Stencil Lithography for Multidimensional

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Utilization of Resist Stencil Lithography for MultiDimensional Fabrication on Curved Surface Hongbing Cai, Qiushi Meng, Huaiyi Ding, Kun Zhang, Yue Lin, Wenzhen Ren, Xinxin Yu, Yukun Wu, Guanghui Zhang, Mingling Li, Nan Pan, Zeming Qi, Yang-Chao Tian, Yi Luo, and Xiaoping Wang ACS Nano, Just Accepted Manuscript • DOI: 10.1021/acsnano.8b06534 • Publication Date (Web): 06 Sep 2018 Downloaded from http://pubs.acs.org on September 7, 2018

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Utilization of Resist Stencil Lithography for MultiDimensional Fabrication on Curved Surface Hongbing Cai†,‡,#, Qiushi Meng†,#, Huaiyi Ding†, Kun Zhang†,‡, Yue Lin†, Wenzhen Ren†, Xinxin Yu§, Yukun Wu∥, Guanghui Zhang∥, Mingling Li†, Nan Pan†, Zeming Qi⊥, Yangchao Tian⊥, Yi Luo†,‡*, Xiaoping Wang†,‡,∥*

†Hefei National Laboratory for Physical Sciences at the Microscale & Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, Hefei Anhui 230026, China. ‡

USTC Center for Micro- and Nanoscale Research and Fabrication, University of Science and Technology of China, Hefei Anhui 230026, China. §

∥Department

Physics School, Anhui University, Hefei Anhui 230601 China.

of Physics, University of Science and Technology of China, Hefei Anhui 230027, China.

⊥

National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei Anhui 230027, China.

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E-mail: [email protected], [email protected]

KEYWORDS: Resist stencil lithography; curved surface; multi-dimensional fabrication; wavy nanostructures; curved gratings.

ABSTRACT: The limited ability to fabricate nanostructures on nonplanar rugged surfaces has severely hampered the applicability of many emerging technologies. Here we report a resist stencil lithography based approach for in-situ fabrication of multi-dimensional nanostructures on both planar and uneven substrates. By using the resist film as a flexible stencil to form suspending membrane with pre-designed patterns, a variety of nanostructures have been fabricated on curved or uneven substrates of diverse morphologies on demand. The ability to realize 4 inch wafer scale fabrication of nanostructures as well as the line width resolution of sub-20 nm is also demonstrated. Its extraordinary capacity is highlighted by the fabrication of three-dimensional wavy nanostructures with diversified cell morphologies on substrates of different curvatures. A robust general scheme is also developed to construct various complex 3D nanostructures. The use of conventional resists and processing ensures the versatility of the method. Such an in-situ lithography technique has offered exciting possibilities to construct nanostructures with high dimensionalities that can otherwise not be achieved with existing nanofabrication methods.

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Planar lithography has played a critical role in the progress of modern electronics. However, the demands for non-planar lithography at irregular surfaces with changeable morphologies has become urgent for epidermal device,1, 2 flexible electronics,3, 4 plasmonics,5, 6 and bionics.7 It is known that the most well-established top-down lithography techniques, such as electron beam lithography (EBL), deep ultraviolet (DUV) lithography and focused ion beam (FIB) , can only be used to fabricate nano-structures on planar substrates due to the intrinsic limitation of photoresist spin-coating and the focus of the beam. Many efforts have been made to circumvent the problems through the elastic transfer printing,2, 8, 9 the direct writing10, 11 and the deformation of flexible substrates.7, 12-16 Each of these approaches works well for certain applications but has some inherent weaknesses. It either requires special materials for nanostructures, stamps and substrates employed, or faces the problems of deformations, cracks and the loss of structure elements during the fabricating process. Among all the methods that intend to realize the nonplanar fabrication, stencil lithography is a resist free fabrication method with many advantages, which usually employs a solid thin film such as Si3N4 membrane as the shadow mask.17,

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It is noticed that in order to fabricate

nanostructures on non-planer substrates, some flexible stencils were introduced with good performance for microscale patterning.19-21 However, those proposed techniques such as the use of polydimethylsiloxane (PDMS) film often involve in complicated stencil fabrication process and have very limited ability to reach the nanoscale resolution. Moreover, the lack of alterable patterning capability has further hampered their applicability. RESULTS AND DISSCUSSIONS


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Here we proposed a resist stencil lithography (RSL) based approach to fabricate nano-structures on curved substrates through the introduction of soft resist stencil.

This technique allows

employing commonly used resists and is compatible with the conventional planar lithography techniques. The typical fabrication process with PMMA resist as an example is described in Figure 1a. The desirable nano patterns were first produced by EBL in PMMA resist on Si/SiO2 substrate. The developed sample was then immersed in 1 M KOH solution at 95 °C. The hydrolyzed SiO2 film became the sacrificial layer to detach the patterned PMMA membrane that was ready to be used as a flexible stencil for the following nanofabrication.22 The highly flexible soft PMMA stencil could be stretched smoothly on the curved substrate23 after dragged out from the deionized water. The evaporation of the water could then make the soft stencil tightly attached onto the surface of the substrate thanks to the capillary force between the membrane and the substrate. After the deposition or growth of required materials into the patterned PMMA stencil, and detaching the mask in deionized water, the designed nanostructures could be finally made onto the non-planar substrate. We have successfully fabricated a variety of nanostructures on different types of curved substrates. The first example, as shown in Figure 1b, is the fabrication of high quality gold nanowire grating on the half-cylinder substrate made of AZ resist. It is known that fibers are probably the most widely used optical elements and their surface modification can gives rise to many specialized applications. In Figure 1c, we show the full pattern of gold nanorod arrays on the entire fiber surface with a diameter of 125 µm. To achieve that, a special alignment of the stencil and deposition method was introduced, which is fully described in Figure S1. The magnified SEM images at different sites, such as the middle and the edge of the fiber, given in Figures 1d-g clearly show the high uniformity of the nanorods array.


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The RSL method also works well on the poly-symmetric surface by the expansion deformation of the resist membrane. In Figure 2a, we demonstrate its fabricating ability on a convex lens surface. From the SEM images in Figures 2b-2d we can see that ultrafine split-ring resonators (SRR) are arrayed uniformly on the middle and the edge of the convex surface with the radius of curvature about 7.7 mm. In Figure 2e, the magnified SEM image corresponding to the SRR elements given in Figure 2d is displayed, which demonstrates that by using RSL method metastructures with the smallest feature size of sub-40 nm can be utilized in a controlled manner. Moreover, by using a thinner PMMA with the thickness of about 100 nm, the limitation of the smallest feature size can go below 20 nm both in the stencil (Figure S2a) and the as-prepared metal nanostructures (Figure S2b). It is noted that the typical size of the stencil employed in this study is about 10 mm×10 mm as shown in Figure S3a. However, the ability of transferring a PMMA and photoresist stencil as large as 4 inch to the convex surface can also be achieved as illustrated in Figure S3b-c. The wafer scale fabrication of nano-electrodes on the curved surface is displayed in Figures 2f-2h. The typical width of the gap between the electrodes can be as small as about 36 nm. We have found that the size of the patterns shrank uniformly after the stencil was peeled off from the original substrate (Figure S4), but there was no visible size change when the stencil was transferred to the substrates of different morphologies. The most exciting advantage of the RSL method is to fabricate complex three-dimensional (3D) wavy nanostructures on different substrates with excellent controllability and multiple modulability. A variety of 3D nanostructures were constructed on uneven substrate with sacrificial microscale convex protrusion following the process flow given in Figure 3a. Specifically, the cuboid PMMA bases were firstly fabricated on the silicon substrate with EBL. After sending the sample into the oven to bake at 130 oC for 30 minutes, the vitrified PMMA


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was shrank from cuboid wires to half-cylinder wires (HCWs) as shown in Figure S5. Then, another PMMA stencil with patterned nanoslits pre-made by the procedure described in Figure 1 could then be transferred on the basal PMMA HCWs. In order to place the stencil on the right place on the basal PMMA HCWs, two different alignment methods were employed as illustrated in Figure S6. After a conformal contact of the flexible stencil onto the curved PMMA basal surface, evaporated material was deposited through the slits on the flexible stencil to form wavy metal belts along the curved surface. Finally, the PMMA stencil was detached from the underneath molds to keep the metal nanostructures on their surface. After dissolving the underlying PMMA HCWs in acetone, the metallic 3D nanostructures were arranged on the substrate. The as prepared wavy nanorings have attracted considerable attentions not only because of its isotropic optical properties which can be used as fundamental metastructure elements, but also due to its potential application as flexible skeleton in bionics or robotics.24, 25 With our RSL method, it is now possible to fabricate the metallic nanorings on almost any substrate with negligible internal stress or manufacturing defect as shown in Figure 3. By the modification of the PMMA stencil and the underlying molds, we can conveniently arrange the period, geometry, size and orientation of the nanorings array to manipulate their scattering properties. These results are collected and shown in Figure 3 and Figure S7. The modulation ability of the wavy nanoblets (also named as air-bridge) as metasurface is examined by fabricating a series of wavy nanobelts with different spans ranged from about 0.88 µm to 3.86 µm as shown in Figure 3b to j, for which the distances between each air-bridges remain the same of 2 µm. The obvious red-shift of the peak as the function of the span length can be observed in reflective IR spectra in Figure 3k, which directly demonstrates the capability to modulate the optical properties of the wavy nanobelts by controllable structure modifications.


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By the special treatment of the underlying PMMA mold, other irregular nanostructures shown in Figures 4 can also be obtained. It started with place the PMMA stencil on the curved edge of the basal PMMA layer. Nanobelts with circular arc shape could be formed after the metal deposition. By removing the basal PMMA layer in the acetone, the nanoblets on the basal film would partially collapse to form asymmetric air-bridges in Figure 4a. The air-bridges array with a gradually varied span in Figure 4b was fabricated by the use of a basal PMMA HCWs with gradually varied width. The hooklike nanobelts in Figure 4c were fabricated using a glancingangle deposition with the direction vertical to the basal PMMA HCWs. Moreover, we can also improve the controllability of the metastructures by adding multivariate in one cell. In Figure 4d and 4e, two and three nanorings of different sizes in one metastructure cell are made by using the cover of PMMA stencil onto the neighbor basal PMMA HCWs with different widths. In Figure 4f, we show the complex metastructures with two crossed nanorings in one cell by fabricating nanobelts on two basal PMMA HCWs gradually moving together. The RSL method also can fabricate the wavy nanobelts with different shape in one cell to form more complex metastructures that are difficult to be realized by other methods. For instance, the image in Figure 4g shows the wavy nanobelts array with periodically changed width in the direction vertical to the metal lines. By using a discontinued PMMA basal rod, we can also fabricate a more complicated metasurface, in which wavy belts and planar belts are interpenetrated to each other, as shown in Figure 4h. It should be noted that the previous strategy that uses buckling stretching on flexible substrates has gained some popularities in fabricating nanodevices.3, 24, 26 However, the in-situ fabrication of such nanodevices still faces formidable engineering challenges in manufacturing. We demonstrate here that such a difficulty can be overcome to some extent by our proposed RSL


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method. Figure S8a shows the gold nanorings array on the flexible substrate made by PDMS (Sylgard 184, Dow Corning). Due to the flexibility of PDMS, the as-prepared nanorings can be compressed and bended to modify their optical properties. The SEM images in Figure S8b, indicate that even at a compress ratio of 20% the nanorings remain undamaged, illustrating their potential applications for flexible devices. Moreover, in Figure S8c, nanorings with different width are successfully prepared on the fiber surface by the transfer of PMMA nanowires mold to the fiber. We will further show that the RSL method can produce various flexible stencils with different resist and the results are given in Figure 5. UV lithography is an essential technology for the electronics industry, but it has not been possible to operate on nonplanar substrates. The RSL method offers an indirect solution to this problem by transferring the patterned photoresist from the Si surface to the nonplanar substrate. As shown in Figures 5a, b, widely used photoresist ARP 5350 is employed to achieve this goal with the proposed procedures. In order to avoid the chemical reaction of the resist in the transfer solution, we chose Cu film as the sacrificial layer instead of SiO2 film in this case and the photoresist membrane was detached from the substrate in the 0.1 g/mL FeCl3 solution. In Figures 5c, d, another negative photoresist SU-8 2025 is used to realize the nonplanar patterning on the curved surface. Furthermore, we also demonstrate the stacking ability to produce multilayers with different resists on the same nonplanar surface by repeatedly applying the RSL method. The first layer of honeycomb SU-8 patterns is transferred to a rod surface in Figure 5e. The sample is then covered by a new layer of PMMA with dense gridding as shown in Figure 5f. The stacking ability of different resists not only enables us to fabricate more complex nanostructures, but also the resist itself can serve as the component of dielectrics metastructures.27, 28


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An intriguing aspect of fabricating nanostructures on a surface of a lens is to achieve the integration of multifunction components in a relative small space that can introduce many properties different from the usual optical elements.29 In this case, the ability to fabricate on the curved surface is essential. We have successfully attached the gold nanorods array on the surface of a convex. As schematically shown in Figure 6a, the spectrometer and focus lens of the convex grating is combined together in one structure. The gold nanorods array fabricated by RSL method is displayed in Figure 6b, in which the iridescent area due to the alignment of periodical structures can be clearly seen. From the SEM image in Figure 6c, the gold nanorods have a uniform size of 1500 nm×300 nm, which highlights the excellent performance of the RSL method in fabricating nanostructures with arbitrary shape on such a curved surface. Two coaxial parallel lasers of the same light spot size with the wavelength of 532 nm and 633 nm, respectively, are used as the incident light in Figure 6a. The diffraction spectrum indicates that this nanostructure works as beam splitting and focuses on just one surface (See Figure S9). It is known that the distance between the first order green and red diffraction spots is determined by f∆λ/p, where p~2.5 µm is the period of the two dimensional grating, the focus length of the lens, f , is about 35 mm and ∆λ is the wavelength difference of two incident lights (101 nm). The calculated distance is estimated to be about 1.4 mm, which is well reproduced by the measured value of 1.3 mm. We also apply this method on the surface of the concave lens to fabricate the widely used concave grating as schematically shown in Figure 6e. The expected dispersion ability is observed from the diffraction spectrum of a white light in Figure 6f, which also reflects the ability to integrate multifunctions in one structure. We could identify at least four advantages for our proposed RSL approach with respect to previously reported nonplanar lithography methods. Firstly, our method naturally inherits the


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good properties of the conventional planar lithography. For example, when the e-beam resist is chosen as the stencil film, the fabrication of masks inherits the high resolution of EBL processes (Figure S2). While with the choice of the photoresist, the high throughput and low cost fabrication of masks can be naturally realized. Secondly, the in-situ fabrication with the resist mask enables to construct nanostructures from different types of materials and synthetic methods. Thirdly, the flexibility and tunable thickness of the resist membrane allow the stencil to be conformably attached to a variety of nonplanar substrates.30 As shown in Figure S10, the thinner the resist stencil is, the more conformable it will be. Fourthly, the as-grown nanostructures do not carry any stresses possibly induced by the transfer or deformation process, resulting in much more stable nano-patterns. In other words, our RSL method has the ability to fabricate complex nanostructures that are otherwise very difficult, if not completely impossible, to utilize by other methods. CONCLUSION In summary, we have applied resist stencil as the lithography mask to successfully fabricate multi-dimensional nanostructures on non-planar substrates of different materials. Thanks to the flexibility of resist membrane, the soft stencil can attach comfortably to non-planar surfaces of different types, while the following-up deposition process gives more choices of materials to construct nanostructures. Its versatility and high resolution strongly suggest that the RSL method is a powerful tool that is ready to be employed for practical fabrication of nanostructures on arbitrary non-planar substrates that are essential for applications in optics, optoelectronic, robotics and bionics. METHODS


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Electronic beam lithography. The patterns in PMMA membrane were fabricated with EBL. A PMMA (950K, 4 wt% in chlorobenzene) electron beam resist was firstly spin-coated onto the substrate at an initial rotary speed of 700 rpm for 20 s and then at 2000 rpm for 35 s. The sample was then baked atmospherically on a hot plate at 180 °C for 2 min and was naturally cooled down to room temperature. The thickness of PMMA was about 280 nm. After baking, the PMMA was exposed in an EBL system (Raith e_Line). Fabrication of the basal half-cylinders wires (HCWs). AZ cuboid on silicon was first fabricated with UV light lithography, using an AZ photoresist (AZ 9260, Shipely). The photoresist is spinning coating at 2000 rpm, baking on hot plate at 110 °C for 5 minutes and then repeating the former processes again, to form cubic grating nanowires with a height of 40 µm and widths ranging from 40 µm to 100 µm. The AZ gratings were then annealed in an oven for 2 hours at 95 °C, and cooled down to room temperature naturally. Because of the glass transition of the AZ photoresist, the cubic gratings shrunk to be half cylinders with the width remaining almost unchanged. PMMA cuboid on silicon was fabricated by EBL and its thickness was about 1.2 µm (PMMA, AR-P 671.06, 6 wt% in chlorobenzene), then the sample was annealed in an oven for 30 minutes at 130 °C, and cooled down to room temperature to form PMMA HCWs. Metal deposition. The metal deposition was carry out in the E-beam evaporator system with the rate of 0.6 Å/s. In order to get a well collimation in the deposition process, the metallic source was chosen to be smaller than 3 mm while the distance from the crucible to the substrate was more than 1 m. The typical thickness of the obtained metallic structures was about 55nm. (5 nm Ti and 50 nm Au). However, in order to get a full patterning on entire fiber surface and avoid the deposition of metal film on the sidewall of the resist patterns caused by the loss of


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collimation, a slit was used in the deposition and the fiber was rotated to get a uniform metallic pattern as shown in Figure S1.


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Figure 1. Fabrication of nanostructures on non-planar substrates using resist stencil lithography with flexible PMMA membrane. (a) Schematic process flow of the RSL method. Nanopatterns on PMMA resist are produced by EBL and the silicon substrate is covered with 300 nm thickness silicon oxide layers. Then PMMA layer is hydrolyzed to detach from the substrate as a soft stencil transferred to the non-planar substrates for the further fabrication. Finally, after removal of PMMA membrane, the as-prepared nanostructures are maintained on the non-planar substrate. (b) Gold nanowires grating on AZ resist half-cylinder substrate. (c-d) Fabrication of gold nanorods array on glass fiber surface with the diameter of 125 µm and (e-g) its magnified SEM images of different places on the fiber surface.


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Figure 2. Fabrication of nanostructures on convex surface. (a) Photography and (b-d) magnified SEM images of gold SRR array on the different places of the convex lens surface. (e) Magnified SEM image of the SRRs on the curved substrate given in Figure 2d. (f) Wafer scale fabricating of nano-electrodes array on curved surface. (g-h) The magnified SEM image of a single nanogap electrode, and the gap between the electrodes was about 36 nm.


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Figure 3. The fabrication of wavy belts and its application as metastructures. (a) Schematic draws of fabrication process for nano-rings array. PMMA nano-cuboid wire array is firstly fabricated on Si/SiO2 substrate with EBL, its shape is deformed from cuboid to half cylinder when annealed in oven below its glass transition temperature, another PMMA membrane with nanoslits as a soft stencil is transferred to the non-planar substrates for metal deposition, nanorings are finally made after removal of PMMA membrane and underneath half cylinder. (bj) The fabricated wavy gold belts with the width ranged from 0.88 µm to 3.86 µm. (k) The modulation of reflective IR spectra of the wavy belts with respect to the width of the air-bridges.


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Figure 4. Schematics of fabricating process and SEM images of 3D metastructures with different morphologies. (a) Asymmetric nano-rings gold belt. (b) Array with gradual changed width. (c) Fishhook-like gold belts by controlling deposition angle. (d-e) Two and three arrays of wavy nanoblets with different width and height composed in one cell of the metastructure. (f) Two arrays of wavy nanoblets that gradually merge. (g) Wavy belts with different period size in the direction vertical to the metal belts. (h) Metastructures composed of wavy belts and planar belts that are interspersed with each other.


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Figure 5. Applications of RSL method with different resists for flexible stencil on nonplanar surface. (a) SEM image of the patterned positive photoresist AR-P 5350 on the quartz capillary surface and b) its magnified image. (c) Photography of the patterned negative photoresist SU8 2025 on the convex cylindrical lens surface and (d) its magnified SEM image. (e) SEM image of the first SU-8 2025 stencil layer on a rod surface and (f) Complex patterns resist stencil composed with a secondary patterned PMMA stencil on the first SU-8 layer in Figure 5e.


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Figure 6. Fabrication of nanostructures on the surface of optical elements. (a) Schematics of the nanorods array on convex lens to make it a spectrophotometer with self-focus. The transmission light with different wave length are focus on different point. (b) Fabrication of gold nanorods array on a surface of convex lens with the focus length of 35 mm. (c) SEM images of gold nanostructures in the lens’ nonplanar surface of Figure 6b. (d) Spectrum of two coaxial parallel green and red laser with the same size of light spots propagated through the convex grating surface. (e) Schematics of gold nanorods array on a surface of concave lens with the focus length of 27 mm. (f) Spectrum of white light reflected from the gold nanorods array on concave lens surface. .


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ASSOCIATED CONTENT Supporting Information. The Supporting Information is available free of charge on the ACS Publications website at DOI: Full patterning on fiber surface , typical performance of the stencil, fabrication of half-cylinder basal wires, alignment method of the RSL, the application of RSL method for the 3D fabrication, integration of multifunction by the convex grating, and contact of the stencil with the non-planar after transfer. (PDF) AUTHOR INFORMATION Corresponding Author *E-mail: [email protected]. *E-mail: [email protected]. ORCID Hongbing Cai: 0000-0003-3186-1041 Huaiyi Ding: 0000-0002-2512-4013 Yue Lin: 0000-0001-5333-511X Xiaoping Wang: 0000-0002-8296-385X Author Contributions #

These authors contributed equally.


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H.B.C., Y.L. and X.P.W. supervised the project and designed the experiments. H.B.C., H.Y.D., K.Z., Y.L., W.Z.R., X.X.Y., Y.K.W., G.H.Z., Q.S.M, M.L.L., N.P., Z.M.Q. and Y.C.T. performed experiments and analyzed data. H.B.C., X.P.W. and Y.L. wrote the manuscript.

ACKNOWLEDGMENT We thank G. Liu, Y. Xiong, W. Z. Ren and Y. Y. Wang for helpful discussion. This work was supported by the Ministry of Science and Technology of China (2016YFA0200602, 2017YFA0303500), the Natural Science Foundation of China (21421063, 21633007, 21790350, 11504359, 11474260, 11504364), Anhui Initiative in Quantum Information Technologies (AHY090200)，the Fundamental Research Funds for the Central Universities and Hefei Science Center of the Chinese Academy of Sciences (2016HSC-IU003). This work was partially carried out at the USTC Center for Micro and Nanoscale Research and Fabrication REFERENCES (1)

Kim, D.-H.; Lu, N.; Ma, R.; Kim, Y.-S.; Kim, R.-H.; Wang, S.; Wu, J.; Won, S. M.; Tao,

H.; Islam, A.; Yu, K. J.; Kim, T.-i.; Chowdhury, R.; Ying, M.; Xu, L.; Li, M.; Chung, H.-J.; Keum, H.; McCormick, M.; Liu, P.; et al. Epidermal Electronics. Science 2011, 333, 838-843. (2)

Liu, Y.; Norton, J. J. S.; Qazi, R.; Zou, Z.; Ammann, K. R.; Liu, H.; Yan, L.; Tran, P. L.;

Jang, K.-I.; Lee, J. W.; Zhang, D.; Kilian, K. A.; Jung, S. H.; Bretl, T.; Xiao, J.; Slepian, M. J.; Huang, Y.; Jeong, J.-W.; Rogers, J. A. Epidermal Mechano-Acoustic Sensing Electronics for Cardiovascular Diagnostics and Human-Machine Interfaces. Science Advances 2016, 2, e1601185.


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(3)

Page 22 of 25

Jang, K. I.; Li, K.; Chung, H. U.; Xu, S.; Jung, H. N.; Yang, Y. Y.; Kwak, J. W.; Jung, H.

H.; Song, J.; Yang, C.; Wang, A.; Liu, Z. J.; Lee, J. Y.; Kim, B. H.; Kim, J. H.; Lee, J.; Yu, Y.; Kim, B. J.; Jang, H.; Yu, K. J.; et al. Self-Assembled Three Dimensional Network Designs for Soft Electronics. Nat. Commun. 2017, 8, 15894. (4)

Rogers, J. A.; Someya, T.; Huang, Y. G. Materials and Mechanics for Stretchable

Electronics. Science 2010, 327, 1603-1607. (5)

Cai, H.; Ren, W.; Zhang, K.; Tian, Y.; Pan, N.; Luo, Y.; Wang, X. Fabrication of

Metallic Nanopatterns with Ultrasmooth Surface on Various Substrates through Lift-Off and Transfer Process. Opt. Express 2013, 21, 32417-32424. (6)

Yoo, D.; Johnson, T. W.; Cherukulappurath, S.; Norris, D. J.; Oh, S. H. Template-

Stripped Tunable Plasmonic Devices on Stretchable and Rollable Substrates. ACS Nano 2015, 9, 10647-10654. (7)

Song, Y. M.; Xie, Y. Z.; Malyarchuk, V.; Xiao, J. L.; Jung, I.; Choi, K. J.; Liu, Z. J.;

Park, H.; Lu, C. F.; Kim, R. H.; Li, R.; Crozier, K. B.; Huang, Y. G.; Rogers, J. A. Digital Cameras with Designs Inspired by the Arthropod Eye. Nature 2013, 497, 95-99. (8)

Meitl, M. A.; Zhu, Z. T.; Kumar, V.; Lee, K. J.; Feng, X.; Huang, Y. Y.; Adesida, I.;

Nuzzo, R. G.; Rogers, J. A. Transfer Printing by Kinetic Control of Adhesion to an Elastomeric Stamp. Nat. Mater. 2006, 5, 33-38. (9)

Li, Z.; Gu, Y.; Wang, L.; Ge, H.; Wu, W.; Xia, Q.; Yuan, C.; Chen, Y.; Cui, B.;

Williams, R. S. Hybrid Nanoimprint-Soft Lithography with Sub-15 nm Resolution. Nano Lett. 2009, 9, 2306-10.


22

Page 23 of 25 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

ACS Nano

(10) Pfeiffer, C.; Xu, X.; Forrest, S. R.; Grbic, A. Direct Transfer Patterning of Electrically Small Antennas onto Three-Dimensionally Contoured Substrates. Adv. Mater. 2012, 24, 11661170. (11) Thiele, S.; Arzenbacher, K.; Gissibl, T.; Giessen, H.; Herkommer, A. M. 3D-Printed Eagle Eye: Compound Microlens System for Foveated Imaging. Science Advances 2017, 3, e1602655. (12) Ko, H. C.; Stoykovich, M. P.; Song, J. Z.; Malyarchuk, V.; Choi, W. M.; Yu, C. J.; Geddes, J. B.; Xiao, J. L.; Wang, S. D.; Huang, Y. G.; Rogers, J. A. A Hemispherical Electronic Eye Camera Based on Compressible Silicon Optoelectronics. Nature 2008, 454, 748-753. (13) Kim, D. H.; Ahn, J. H.; Choi, W. M.; Kim, H. S.; Kim, T. H.; Song, J. Z.; Huang, Y. G. Y.; Liu, Z. J.; Lu, C.; Rogers, J. A. Stretchable and Foldable Silicon Integrated Circuits. Science 2008, 320, 507-511. (14) Wang, S.; Weil, B. D.; Li, Y.; Wang, K. X.; Garnett, E.; Fan, S.; Cui, Y. Large-Area Free-Standing Ultrathin Single-Crystal Silicon as Processable Materials. Nano Lett. 2013, 13, 4393-4398. (15) Li, N.; Bedell, S.; Hu, H.; Han, S.-J.; Liu, X. H.; Saenger, K.; Sadana, D. Single Crystal Flexible Electronics Enabled by 3D Spalling. Adv. Mater. 2017, 29, 1606638. (16) Tran Quang, T.; Lee, N.-E. Recent Progress on Stretchable Electronic Devices with Intrinsically Stretchable Components. Adv. Mater. 2017, 29, 1603167.


23

ACS Nano 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 24 of 25

(17) Flauraud, V.; van Zanten, T. S.; Mivelle, M.; Manzo, C.; Garcia Parajo, M. F.; Brugger, J. Large-Scale Arrays of Bowtie Nanoaperture Antennas for Nanoscale Dynamics in Living Cell Membranes. Nano Lett. 2015, 15, 4176-4182. (18) Yesilkoy, F.; Flauraud, V.; Rueegg, M.; Kim, B. J.; Brugger, J. 3D Nanostructures Fabricated by Advanced Stencil Lithography. Nanoscale 2016, 8, 4945-4950. (19) Pendergraph, S. A.; Park, J. Y.; Hendricks, N. R.; Crosby, A. J.; Carter, K. R. Facile Colloidal Lithography on Rough and Non-planar Surfaces for Asymmetric Patterning. Small 2013, 9, 3037-3042. (20) Choi, J. H.; Kim, G. M. Micro-Patterning on Non-Planar Surface Using Flexible Microstencil. Inter.J. Precis. Eng. Man. 2011, 12, 165-168. (21) Xia, Y. N.; Kim, E.; Whitesides, G. M. Micromolding of Polymers in Capillaries: Applications in Microfabrication. Chem. Mater. 1996, 8, 1558-1567. (22) Shih, F.-Y.; Chen, S.-Y.; Liu, C.-H.; Ho, P.-H.; Wu, T.-S.; Chen, C.-W.; Chen, Y.-F.; Wang, W.-H. Residue-Free Fabrication of High-Performance Graphene Devices by Patterned PMMA Stencil Mask. AIP Advances 2014, 4, 067129. (23) Wang, L.; Qiao, S.; Ameri, S. K.; Jeong, H.; Lu, N. A Thin Elastic Membrane Conformed to a Soft and Rough Substrate Subjected to Stretching/Compression. J. Appl. Mech.T. Asme 2017, 84, 111003. (24) Xu, S.; Yan, Z.; Jang, K.-I.; Huang, W.; Fu, H.; Kim, J.; Wei, Z.; Flavin, M.; McCracken, J.; Wang, R.; Badea, A.; Liu, Y.; Xiao, D.; Zhou, G.; Lee, J.; Chung, H. U.; Cheng, H.; Ren, W.;


24

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ACS Nano

Banks, A.; Li, X.; et al. Assembly of Micro/nanomaterials into Complex, Three-Dimensional Architectures by Compressive Buckling. Science 2015, 347, 154-159. (25) Yan, Z.; Zhang, F.; Liu, F.; Han, M.; Ou, D.; Liu, Y.; Lin, Q.; Guo, X.; Fu, H.; Xie, Z.; Gao, M.; Huang, Y.; Kim, J.; Qiu, Y.; Nan, K.; Kim, J.; Gutruf, P.; Luo, H.; Zhao, A.; Hwang, K.-C.; et al. Mechanical Assembly of Complex, 3D Mesostructures from Releasable Multilayers of Advanced Materials. Science Advances 2016, 2, e1601014. (26) Sun, Y. G.; Choi, W. M.; Jiang, H. Q.; Huang, Y. G. Y.; Rogers, J. A. Controlled Buckling of Semiconductor Nanoribbons for Stretchable Electronics. Nat. Nanotechnol. 2006, 1, 201-207. (27) Arbabi, A.; Horie, Y.; Bagheri, M.; Faraon, A. Dielectric Metasurfaces for Complete Control of Phase and Polarization with Subwavelength Spatial Resolution and High Transmission. Nat. Nanotechnol. 2015, 10, 937-944. (28) Jahani, S.; Jacob, Z. All-Dielectric Metamaterials. Nat. Nanotechnol. 2016, 11, 23-36. (29) Kamali, S. M.; Arbabi, A.; Arbabi, E.; Horie, Y.; Faraon, A. Decoupling Optical Function and Geometrical Form Using Conformal Flexible Dielectric Metasurfaces. Nat. Commun. 2016, 7, 11628. (30) Kim, J.; Wang, Y.; Park, H.; Park, M. C.; Moon, S. E.; Hong, S. M.; Koo, C. M.; Suh, K.-Y.; Yang, S.; Cho, H. Nonlinear Frameworks for Reversible and Pluripotent Wetting on Topographic Surfaces. Adv. Mater. 2017, 29, 1605078.


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Utilization of Resist Stencil Lithography for Multidimensional

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