石墨烯,一種二維的平面材料,由於材料的特異性使得在電子元件 化學 與生物領域均帶來革命性的衝擊,然而目前挑戰在於如何製造出高品質的石墨烯 .
CVD成長法是一種能夠成長出大尺寸同時具有高品質的石墨烯生長法 然而這種方法成長出的石墨烯需要從生長基板轉印到目標基板 傳統的轉映過程需要鍍上高分子做保護層防止在過程中石墨烯的破損 在移除高分子保護層時,高分子的殘留物會吸附在石墨烯上且無法移除 而這些殘留物產生的參雜效果會改變其電性降低石墨烯的品質
在這篇論文裡 我們嘗試利用自己設計的自動轉印系統轉印無高分子保護層之CVD石墨烯藉以得到高品質 低殘留的石墨烯 藉由自動轉印系統可以降低在過程中產生的振動與擾動 使石墨烯可以安穩地完成轉印 我們已成功地將石墨烯完整地轉印到矽基板 並在光學顯微鏡與拉曼光譜儀中確認了轉印石墨烯的高品質 並且從原子力顯微鏡與電子顯微鏡的結果得到如何有效降低並避免蝕刻液的殘留 最後 從電子性質的量測中 石墨烯呈現出低電阻 與高載子遷移率.

Graphene is a two-dimensional material that could revolutionize electronics, chemistry, and biology. One major challenge is to produce high quality graphene on suitable substrates.
While CVD graphene growth can produce high quality graphene at large scale, the choice of growth substrates is very limited and we need to transfer the graphene to other substrates. The conventional transfer process employs a polymer as support layer to protect graphene from tearing or folding during etching and transfer process. However, polymer residue which cannot be removed causes undesired doping and degraded quality of graphene.
Here we report a polymer free graphene transfer method that aims at producing clean graphene. By using an automated transfer system we are able to minimize vibrations and increase the stability of graphene during the transfer process. We successfully conducted graphene transfer to Si substrates without breaking the graphene film.
Characterization by optical microscopy and Raman spectroscopy demonstrate the high quality of the transferred graphene. Atomic force microscopy and electron spectroscopy reveal the importance of process optimization to avoid residue. Finally, electric measurements show high carrier mobility and low sheet resistance

[1] W. H. Lin, T. H. Chen, J. K. Chang, J. I. Taur, Y. Y. Lo, W. L. Lee, et al., "A Direct and Polymer-Free Method for Transferring Graphene Grown by Chemical Vapor Deposition to Any Substrate," Acs Nano, vol. 8, pp. 1784-1791, Feb 2014.
[2] D. Y. Wang, I. S. Huang, P. H. Ho, S. S. Li, Y. C. Yeh, D. W. Wang, et al., "Clean-lifting transfer of large-area residual-free graphene films," Adv Mater, vol. 25, pp. 4521-6, Aug 27 2013.
[3] A. K. Geim and K. S. Novoselov, "The rise of graphene," Nature Materials, vol. 6, pp. 183-191, Mar 2007.
[4] D. S. L. Abergel, V. Apalkov, J. Berashevich, K. Ziegler, and T. Chakraborty, "Properties of graphene: a theoretical perspective," Advances in Physics, vol. 59, pp. 261-482, 2010 2010.
[5] K. S. Novoselov, A. K. Geim, S. V. Morozov, D. Jiang, Y. Zhang, S. V. Dubonos, et al., "Electric field effect in atomically thin carbon films," Science, vol. 306, pp. 666-669, Oct 22 2004.
[6] Y. B. Zhang, Y. W. Tan, H. L. Stormer, and P. Kim, "Experimental observation of the quantum Hall effect and Berry's phase in graphene," Nature, vol. 438, pp. 201-204, Nov 10 2005.
[7] K. I. Bolotin, K. J. Sikes, Z. Jiang, M. Klima, G. Fudenberg, J. Hone, et al., "Ultrahigh electron mobility in suspended graphene," Solid State Communications, vol. 146, pp. 351-355, Jun 2008.
[8] R. R. Nair, P. Blake, A. N. Grigorenko, K. S. Novoselov, T. J. Booth, T. Stauber, et al., "Fine structure constant defines visual transparency of graphene," Science, vol. 320, pp. 1308-1308, Jun 6 2008.
[9] W. Cai, A. L. Moore, Y. Zhu, X. Li, S. Chen, L. Shi, et al., "Thermal Transport in Suspended and Supported Monolayer Graphene Grown by Chemical Vapor Deposition," Nano Letters, vol. 10, pp. 1645-1651, May 2010.
[10] C. Lee, X. Wei, J. W. Kysar, and J. Hone, "Measurement of the elastic properties and intrinsic strength of monolayer graphene," Science, vol. 321, pp. 385-388, Jul 18 2008.
[11] Y. M. Lin, C. Dimitrakopoulos, K. A. Jenkins, D. B. Farmer, H. Y. Chiu, A. Grill, et al., "100-GHz Transistors from Wafer-Scale Epitaxial Graphene," Science, vol. 327, pp. 662-662, Feb 5 2010.
[12] Y.-M. Lin, A. Valdes-Garcia, S.-J. Han, D. B. Farmer, I. Meric, Y. Sun, et al., "Wafer-Scale Graphene Integrated Circuit," Science, vol. 332, pp. 1294-1297, Jun 10 2011.
[13] H. Yang, J. Heo, S. Park, H. J. Song, D. H. Seo, K. E. Byun, et al., "Graphene barristor, a triode device with a gate-controlled Schottky barrier," Science, vol. 336, pp. 1140-3, Jun 1 2012.
[14] M. Hempel, D. Nezich, J. Kong, and M. Hofmann, "A novel class of strain gauges based on layered percolative films of 2D materials," Nano Lett, vol. 12, pp. 5714-8, Nov 14 2012.
[15] F. Schedin, A. K. Geim, S. V. Morozov, E. W. Hill, P. Blake, M. I. Katsnelson, et al., "Detection of individual gas molecules adsorbed on graphene," Nature Materials, vol. 6, pp. 652-655, Sep 2007.
[16] J. D. Fowler, M. J. Allen, V. C. Tung, Y. Yang, R. B. Kaner, and B. H. Weiller, "Practical Chemical Sensors from Chemically Derived Graphene," Acs Nano, vol. 3, pp. 301-306, Feb 2009.
[17] F. Xia, T. Mueller, Y.-m. Lin, A. Valdes-Garcia, and P. Avouris, "Ultrafast graphene photodetector," Nature Nanotechnology, vol. 4, pp. 839-843, Dec 2009.
[18] W. Xuan, Z. Linjie, and K. Mullen, "Transparent, conductive graphene electrodes for dye-sensitized solar cells," Nano Letters, vol. 8, pp. 323-7, Jan. 2008.
[19] H. Park, J. A. Rowehl, K. K. Kim, V. Bulovic, and J. Kong, "Doped graphene electrodes for organic solar cells," Nanotechnology, vol. 21, Dec 17 2010.
[20] L. G. De Arco, Y. Zhang, C. W. Schlenker, K. Ryu, M. E. Thompson, and C. Zhou, "Continuous, Highly Flexible, and Transparent Graphene Films by Chemical Vapor Deposition for Organic Photovoltaics," Acs Nano, vol. 4, pp. 2865-2873, May 2010.
[21] H. Park, P. R. Brown, V. Buloyic, and J. Kong, "Graphene As Transparent Conducting Electrodes in Organic Photovoltaics: Studies in Graphene Morphology, Hole Transporting Layers, and Counter Electrodes," Nano Letters, vol. 12, pp. 133-140, Jan 2012.
[22] S. K. Min, W. Y. Kim, Y. Cho, and K. S. Kim, "Fast DNA sequencing with a graphene-based nanochannel device," Nature Nanotechnology, vol. 6, pp. 162-165, Mar 2011.
[23] P. Dhiman, F. Yavari, X. Mi, H. Gullapalli, Y. Shi, P. M. Ajayan, et al., "Harvesting Energy from Water Flow over Graphene," Nano Letters, vol. 11, pp. 3123-3127, Aug 2011.
[24] W. Hu, C. Peng, W. Luo, M. Lv, X. Li, D. Li, et al., "Graphene-Based Antibacterial Paper," Acs Nano, vol. 4, pp. 4317-4323, Jul 2010.
[25] L. Grande, V. T. Chundi, D. Wei, C. Bower, P. Andrew, and T. Ryhaenen, "Graphene for energy harvesting/storage devices and printed electronics," Particuology, vol. 10, pp. 1-8, Feb 2012.
[26] A. Zurutuza and C. Marinelli, "Challenges and opportunities in graphene commercialization," Nat Nano, vol. 9, pp. 730-734, 10//print 2014.
[27] K. S. Novoselov, V. I. Fal'ko, L. Colombo, P. R. Gellert, M. G. Schwab, and K. Kim, "A roadmap for graphene," Nature, vol. 490, pp. 192-200, Oct 11 2012.
[28] K. S. Novoselov, D. Jiang, F. Schedin, T. J. Booth, V. V. Khotkevich, S. V. Morozov, et al., "Two-dimensional atomic crystals," Proceedings of the National Academy of Sciences of the United States of America, vol. 102, pp. 10451-10453, Jul 2005.
[29] X. K. Lu, M. F. Yu, H. Huang, and R. S. Ruoff, "Tailoring graphite with the goal of achieving single sheets," Nanotechnology, vol. 10, pp. 269-272, Sep 1999.
[30] X. G. Liang, V. Giacometti, A. Ismach, B. D. Harteneck, D. L. Olynick, and S. Cabrini, "Roller-style electrostatic printing of prepatterned few-layer-graphenes," Applied Physics Letters, vol. 96, Jan 2010.
[31] S. Stankovich, D. A. Dikin, G. H. B. Dommett, K. M. Kohlhaas, E. J. Zimney, E. A. Stach, et al., "Graphene-based composite materials," Nature, vol. 442, pp. 282-286, Jul 2006.
[32] W. S. Hummers and R. E. Offeman, "Preparation of Graphitic Oxide," Journal of the American Chemical Society, vol. 80, pp. 1339-1339, 1958/03/01 1958.
[33] D. Li, M. B. Muller, S. Gilje, R. B. Kaner, and G. G. Wallace, "Processable aqueous dispersions of graphene nanosheets," Nat Nanotechnol, vol. 3, pp. 101-5, Feb 2008.
[34] C.-Y. Su, A.-Y. Lu, Y. Xu, F.-R. Chen, A. N. Khlobystov, and L.-J. Li, "High-Quality Thin Graphene Films from Fast Electrochemical Exfoliation," Acs Nano, vol. 5, pp. 2332-2339, Mar 2011.
[35] K. V. Emtsev, A. Bostwick, K. Horn, J. Jobst, G. L. Kellogg, L. Ley, et al., "Towards wafer-size graphene layers by atmospheric pressure graphitization of silicon carbide," Nature Materials, vol. 8, pp. 203-207, Mar 2009.
[36] M. Sprinkle, M. Ruan, Y. Hu, J. Hankinson, M. Rubio-Roy, B. Zhang, et al., "Scalable templated growth of graphene nanoribbons on SiC," Nature Nanotechnology, vol. 5, pp. 727-731, Oct 2010.
[37] Q. Yu, J. Lian, S. Siriponglert, H. Li, Y. P. Chen, and S.-S. Pei, "Graphene segregated on Ni surfaces and transferred to insulators," Applied Physics Letters, vol. 93, Sep 15 2008.
[38] S.-Y. Kwon, C. V. Ciobanu, V. Petrova, V. B. Shenoy, J. Bareno, V. Gambin, et al., "Growth of Semiconducting Graphene on Palladium," Nano Letters, vol. 9, pp. 3985-3990, Dec 2009.
[39] P. W. Sutter, J.-I. Flege, and E. A. Sutter, "Epitaxial graphene on ruthenium," Nature Materials, vol. 7, pp. 406-411, May 2008.
[40] J. Coraux, A. T. N'Diaye, C. Busse, and T. Michely, "Structural coherency of graphene on Ir(111)," Nano Letters, vol. 8, pp. 565-570, Feb 2008.
[41] X. Li, W. Cai, J. An, S. Kim, J. Nah, D. Yang, et al., "Large-Area Synthesis of High-Quality and Uniform Graphene Films on Copper Foils," Science, vol. 324, pp. 1312-1314, Jun 5 2009.
[42] A. N. Obraztsov, E. A. Obraztsova, A. V. Tyurnina, and A. A. Zolotukhin, "Chemical vapor deposition of thin graphite films of nanometer thickness," Carbon, vol. 45, pp. 2017-2021, Sep 2007.
[43] Y. Lee, S. Bae, H. Jang, S. Jang, S.-E. Zhu, S. H. Sim, et al., "Wafer-Scale Synthesis and Transfer of Graphene Films," Nano Letters, vol. 10, pp. 490-493, Feb 2010.
[44] X. Li, Y. Zhu, W. Cai, M. Borysiak, B. Han, D. Chen, et al., "Transfer of Large-Area Graphene Films for High-Performance Transparent Conductive Electrodes," Nano Letters, vol. 9, pp. 4359-4363, Dec 2009.
[45] Y.-H. Lee and J.-H. Lee, "Scalable growth of free-standing graphene wafers with copper(Cu) catalyst on SiO2/Si substrate: Thermal conductivity of the wafers," Applied Physics Letters, vol. 96, Feb 22 2010.
[46] A. Srivastava, C. Galande, L. Ci, L. Song, C. Rai, D. Jariwala, et al., "Novel Liquid Precursor-Based Facile Synthesis of Large-Area Continuous, Single, and Few-Layer Graphene Films," Chemistry of Materials, vol. 22, pp. 3457-3461, Jun 8 2010.
[47] In ASM Handbook Vol. 5 Surface Engineering, 1994
[48] S. Bae, H. Kim, Y. Lee, X. Xu, J.-S. Park, Y. Zheng, et al., "Roll-to-roll production of 30-inch graphene films for transparent electrodes," Nature Nanotechnology, vol. 5, pp. 574-578, Aug 2010.
[49] K. S. Kim, Y. Zhao, H. Jang, S. Y. Lee, J. M. Kim, K. S. Kim, et al., "Large-scale pattern growth of graphene films for stretchable transparent electrodes," Nature, vol. 457, pp. 706-710, Feb 5 2009.
[50] S. J. Clarson and J. A. Semlyen, Siloxane Polymers, Prentice Hall,Englewood Cliffs, NJ, 1993
[51] X.-D. Chen, Z.-B. Liu, C.-Y. Zheng, F. Xing, X.-Q. Yan, Y. Chen, et al., "High-quality and efficient transfer of large-area graphene films onto different substrates," Carbon, vol. 56, pp. 271-278, 2013.
[52] J. Song, F.-Y. Kam, R.-Q. Png, W.-L. Seah, J.-M. Zhuo, G.-K. Lim, et al., "A general method for transferring graphene onto soft surfaces," Nature Nanotechnology, vol. 8, pp. 356-362, May 2013.
[53] J. Kang, S. Hwang, J. H. Kim, M. H. Kim, J. Ryu, S. J. Seo, et al., "Efficient Transfer of Large-Area Graphene Films onto Rigid Substrates by Hot Pressing," Acs Nano, vol. 6, pp. 5360-5365, Jun 2012.
[54] A. Reina, H. Son, L. Jiao, B. Fan, M. S. Dresselhaus, Z. Liu, et al., "Transferring and Identification of Single- and Few-Layer Graphene on Arbitrary Substrates," Journal of Physical Chemistry C, vol. 112, pp. 17741-17744, Nov 20 2008.
[55] Z. Cheng, Q. Zhou, C. Wang, Q. Li, C. Wang, and Y. Fang, "Toward Intrinsic Graphene Surfaces: A Systematic Study on Thermal Annealing and Wet-Chemical Treatment of SiO2-Supported Graphene Devices," Nano Letters, vol. 11, pp. 767-771, Feb 2011.
[56] J. Kedzierski, P.-L. Hsu, A. Reina, J. Kong, P. Healey, P. Wyatt, et al., "Graphene-on-Insulator Transistors Made Using C on Ni Chemical-Vapor Deposition," Ieee Electron Device Letters, vol. 30, pp. 745-747, Jul 2009.
[57] Y.-C. Lin, C.-C. Lu, C.-H. Yeh, C. Jin, K. Suenaga, and P.-W. Chiu, "Graphene Annealing: How Clean Can It Be?," Nano Letters, vol. 12, pp. 414-419, Jan 2012.
[58] W. Regan, N. Alem, B. n. Alemán, B. Geng, C. a. l. Girit, L. Maserati, et al., "A direct transfer of layer-area graphene," Applied Physics Letters, vol. 96, p. 113102, 2010.
[59] Y. Ren, C. Zhu, W. Cai, H. Li, Y. Hao, Y. Wu, et al., "An Improved Method for Transferring Graphene Grown by Chemical Vapor Deposition," Nano, vol. 07, p. 1150001, 2012.
[60] A. C. Ferrari, J. C. Meyer, V. Scardaci, C. Casiraghi, M. Lazzeri, F. Mauri, et al., "Raman spectrum of graphene and graphene layers," Physical Review Letters, vol. 97, Nov 2006.
[61] L. M. Malard, M. A. Pimenta, G. Dresselhaus, and M. S. Dresselhaus, "Raman spectroscopy in graphene," Physics Reports-Review Section of Physics Letters, vol. 473, pp. 51-87, Apr 2009.
[62] Charles Kittel, Introduction to Solid State Physics, 6th ed. (Wiley, New York,1986).
[63] L. J. van der Pauw, "A Method of Measuring Specific Resistivity and Hall Effect of Discs of Arbitrary Shapes," Philips Res. Repts. 13, 1-9 (1958).
[64] E. H. Lock, M. Baraket, M. Laskoski, S. P. Mulvaney, W. K. Lee, P. E. Sheehan, et al., "High-Quality Uniform Dry Transfer of Graphene to Polymers," Nano Letters, vol. 12, pp. 102-107, Jan 2012.