메뉴 건너뛰기




Volumn 5, Issue 10, 2012, Pages 1933-1953

Guidelines for the bandgap combinations and absorption windows for organic tandem and triple-junction solar cells

Author keywords

Absorption window; Bandgap; Modeling; Multi junction solar cells; Organic solar cells; Power conversion efficiency; Tandem solar cells; Triple junction solar cells

Indexed keywords

MULTI JUNCTION SOLAR CELLS; ORGANIC SOLAR CELL; POWER CONVERSION EFFICIENCIES; TANDEM SOLAR CELLS; TRIPLE JUNCTION SOLAR CELLS;

EID: 84870007189     PISSN: None     EISSN: 19961944     Source Type: Journal    
DOI: 10.3390/ma5101933     Document Type: Article
Times cited : (32)

References (54)
  • 1
    • 79954612131 scopus 로고    scopus 로고
    • Outlook brightens for plastic solar cells
    • Service, R.F. Outlook brightens for plastic solar cells. Science 2011, 332, 293-293.
    • (2011) Science , vol.332 , pp. 293-1293
    • Service, R.F.1
  • 4
    • 2042544776 scopus 로고    scopus 로고
    • Low bandgap polymers for photon harvesting in bulk heterojunction solar cells
    • Winder, C.; Sariciftci, N.S. Low bandgap polymers for photon harvesting in bulk heterojunction solar cells. J. Mater. Chem. 2004, 14, 1077-1086.
    • (2004) J. Mater. Chem. , vol.14 , pp. 1077-1086
    • Winder, C.1    Sariciftci, N.S.2
  • 6
    • 34548017181 scopus 로고    scopus 로고
    • Highly efficient organic tandem solar cells using an improved connecting architecture
    • 073519 3
    • Janssen, A.G.F.; Riedl, T.; Hamwi, S.; Johannes, H.H.; Kowalsky, W. Highly efficient organic tandem solar cells using an improved connecting architecture. Appl. Phys. Lett. 2007, 91, 073519:1-073519:3.
    • (2007) Appl. Phys. Lett. , vol.91 , pp. 1-073519
    • Janssen, A.G.F.1    Riedl, T.2    Hamwi, S.3    Johannes, H.H.4    Kowalsky, W.5
  • 7
    • 34648843615 scopus 로고    scopus 로고
    • Folded reflective tandem polymer solar cell doubles efficiency
    • 123514 3
    • Tvingstedt, K.; Andersson, V.; Zhang, F.; Inganas, O. Folded reflective tandem polymer solar cell doubles efficiency. Appl. Phys. Lett. 2007, 91, 123514:1-123514:3.
    • (2007) Appl. Phys. Lett. , vol.91 , pp. 1-123514
    • Tvingstedt, K.1    Andersson, V.2    Zhang, F.3    Inganas, O.4
  • 8
    • 34047249929 scopus 로고    scopus 로고
    • Double and triple junction polymer solar cells processed from solution
    • Gilot, J.; Wienk, M.M.; Janssen, R.A.J. Double and triple junction polymer solar cells processed from solution. Appl. Phys. Lett. 2007, 90, 143512:1-143512:3
    • (2007) Appl. Phys. Lett. , vol.90 , pp. 1143512-3143512
    • Gilot, J.1    Wienk, M.M.2    Janssen, R.A.J.3
  • 9
    • 34447504948 scopus 로고    scopus 로고
    • Efficient tandem polymer solar cells fabricated by all-solution processing
    • Kim, J.Y.; Lee, K.; Coates, N.E.; Moses, D.; Nguyen, T.-Q.; Dante, M.; Heeger, A.J. Efficient tandem polymer solar cells fabricated by all-solution processing. Science 2007, 317, 222-225.
    • (2007) Science , vol.317 , pp. 222-225
    • Kim, J.Y.1    Lee, K.2    Coates, N.E.3    Moses, D.4    Nguyen, T.-Q.5    Dante, M.6    Heeger, A.J.7
  • 12
    • 84860324032 scopus 로고    scopus 로고
    • Solution processed polymer tandem solar cell using efficient small and wide bandgap polymer: Fullerene blends
    • Gevaerts, V.S.; Furlan, A.; Wienk, M.M.; Turbiez, M.; Janssen, R.A.J. Solution processed polymer tandem solar cell using efficient small and wide bandgap polymer: Fullerene blends. Advan. Mater. 2012, 24, 2130-2134.
    • (2012) Advan. Mater. , vol.24 , pp. 2130-2134
    • Gevaerts, V.S.1    Furlan, A.2    Wienk, M.M.3    Turbiez, M.4    Janssen, R.A.J.5
  • 13
    • 14544288595 scopus 로고    scopus 로고
    • Tandem-type organic solar cells by stacking different heterojunction materials
    • Triyana, K.; Yasuda, T.; Fujita, K.; Tsutsui, T. Tandem-type organic solar cells by stacking different heterojunction materials. Thin Solid Films 2005, 477, 198-202.
    • (2005) Thin Solid Films , vol.477 , pp. 198-202
    • Triyana, K.1    Yasuda, T.2    Fujita, K.3    Tsutsui, T.4
  • 16
    • 84870971732 scopus 로고    scopus 로고
    • Heliatek sets new world record efficiency of 10.7% for its organic tandem cell. 2012. Available online (accessed on 27 April 2012)
    • Heliatek, G. Heliatek sets new world record efficiency of 10.7% for its organic tandem cell. 2012. Available online: http://www.heliatek.com/wp-content/uploads/2012/09/120427_PI_Heliatekworld-record-10_7-percent-efficiency.pdf (accessed on 27 April 2012).
    • Heliatek, G.1
  • 17
    • 84863229720 scopus 로고    scopus 로고
    • Polymer solar cells
    • Li, G.; Zhu, R.; Yang, Y. Polymer solar cells. Nat. Photonics 2012, 6, 153-161.
    • (2012) Nat. Photonics , vol.6 , pp. 153-161
    • Li, G.1    Zhu, R.2    Yang, Y.3
  • 18
    • 33645392241 scopus 로고    scopus 로고
    • Design rules for donors in bulk-heterojunction solar cells-towards 10% energy-conversion efficiency
    • Scharber, M.C.; Wuhlbacher, D.; Koppe, M.; Denk, P.; Waldauf, C.; Heeger, A.J.; Brabec, C.L. Design rules for donors in bulk-heterojunction solar cells-towards 10% energy-conversion efficiency. Advan. Mater. 2006, 18, 789-794.
    • (2006) Advan. Mater. , vol.18 , pp. 789-794
    • Scharber, M.C.1    Wuhlbacher, D.2    Koppe, M.3    Denk, P.4    Waldauf, C.5    Heeger, A.J.6    Brabec, C.L.7
  • 19
    • 8544235033 scopus 로고    scopus 로고
    • Conjugated polymer photovoltaic cells
    • Coakley, K.M.; McGehee, M.D. Conjugated polymer photovoltaic cells. Chem. Mater. 2004, 16, 4533-4542.
    • (2004) Chem. Mater. , vol.16 , pp. 4533-4542
    • Coakley, K.M.1    McGehee, M.D.2
  • 20
    • 37549010776 scopus 로고    scopus 로고
    • Design of efficient organic tandem cells: On the interplay between molecular absorption and layer sequence
    • 123109 6
    • Dennler, G.; Forberich, K.; Ameri, T.; Waldauf, C.; Denk, P.; Brabec, C.J.; Hingerl, K.; Heeger, A.J. Design of efficient organic tandem cells: On the interplay between molecular absorption and layer sequence. J. Appl. Phys. 2007, 102, 123109:1-123109:6.
    • (2007) J. Appl. Phys. , vol.102 , pp. 1-123109
    • Dennler, G.1    Forberich, K.2    Ameri, T.3    Waldauf, C.4    Denk, P.5    Brabec, C.J.6    Hingerl, K.7    Heeger, A.J.8
  • 21
    • 33748985664 scopus 로고    scopus 로고
    • Organic tandem solar cells-modelling and predictions
    • Persson, N.-K.; Inganas, O. Organic tandem solar cells-modelling and predictions. Solar Energy Mater. Solar Cells 2006, 90, 3491-3507.
    • (2006) Solar Energy Mater. Solar Cells , vol.90 , pp. 3491-3507
    • Persson, N.-K.1    Inganas, O.2
  • 22
    • 54849415346 scopus 로고    scopus 로고
    • Design rules for donors in bulk-heterojunction tandem solar cells-towards 15% energy-conversion efficiency
    • Dennler, G.; Scharber, M.C.; Ameri, T.; Denk, P.; Forberich, K.; Waldauf, C.; Brabec, C.J. Design rules for donors in bulk-heterojunction tandem solar cells-towards 15% energy-conversion efficiency. Advan. Mater. 2008, 20, 579-583.
    • (2008) Advan. Mater. , vol.20 , pp. 579-583
    • Dennler, G.1    Scharber, M.C.2    Ameri, T.3    Denk, P.4    Forberich, K.5    Waldauf, C.6    Brabec, C.J.7
  • 23
    • 33947701671 scopus 로고    scopus 로고
    • Offset energies at organic semiconductor heterojunctions and their influence on the open-circuit voltage of thin-film solar cells
    • 115327 11
    • Rand, B.P.; Burk, D.P.; Forrest, S.R. Offset energies at organic semiconductor heterojunctions and their influence on the open-circuit voltage of thin-film solar cells. Phys. Rev. B 2007, 75, 115327:1-115327:11.
    • (2007) Phys. Rev. B , vol.75 , pp. 1-115327
    • Rand, B.P.1    Burk, D.P.2    Forrest, S.R.3
  • 25
    • 33646493320 scopus 로고    scopus 로고
    • How to model the behaviour of organic photovoltaic cells
    • Moliton, A.; Nunzi, J.M. How to model the behaviour of organic photovoltaic cells. Polym. Int. 2006, 55, 583-600.
    • (2006) Polym. Int. , vol.55 , pp. 583-600
    • Moliton, A.1    Nunzi, J.M.2
  • 26
    • 31944431810 scopus 로고    scopus 로고
    • Ultimate efficiency of polymer/fullerene bulk heterojunction solar cells
    • 093511 3
    • Koster, L.J.A.; Mihailetchi, V.D.; Blom, P.W.M. Ultimate efficiency of polymer/fullerene bulk heterojunction solar cells. Appl. Phys. Lett. 2006, 88, 093511:1-093511:3.
    • (2006) Appl. Phys. Lett. , vol.88 , pp. 1-093511
    • Koster, L.J.A.1    Mihailetchi, V.D.2    Blom, P.W.M.3
  • 27
    • 77950860606 scopus 로고    scopus 로고
    • Simulation of the influence of the absorption window for stacked and monolithic organic tandem solar cells
    • Minnaert, B.; Burgelman, M.; De Vos, A.; Veelaert, P. Simulation of the influence of the absorption window for stacked and monolithic organic tandem solar cells. Solar Energy Mater. Solar Cells 2010, 94, 1125-1131.
    • (2010) Solar Energy Mater. Solar Cells , vol.94 , pp. 1125-1131
    • Minnaert, B.1    Burgelman, M.2    De Vos, A.3    Veelaert, P.4
  • 28
    • 84862289265 scopus 로고    scopus 로고
    • Modelling of Organic Triple-Junction Solar Cells
    • Proceeding of SPIE 8435, Brussels, Belgium, 16 April 2012; Rand, B.P., Adachi, C., van Elsbergen, V., Eds.; SPIE: Bellingham, WA, USA doi:10.1117/12.921779
    • Minnaert, B.; Veelaert, P. Modelling of Organic Triple-Junction Solar Cells. In Organic Photonics V, Proceeding of SPIE 8435, Brussels, Belgium, 16 April 2012; Rand, B.P., Adachi, C., van Elsbergen, V., Eds.; SPIE: Bellingham, WA, USA, 2012; Volume 8435, doi:10.1117/12.921779.
    • (2012) Organic Photonics V , vol.8435
    • Minnaert, B.1    Veelaert, P.2
  • 29
    • 0022594397 scopus 로고
    • Two-layer organic photovoltaic cell
    • Tang, C.W. Two-layer organic photovoltaic cell. Appl. Phys. Lett. 1986, 48, 183-185.
    • (1986) Appl. Phys. Lett. , vol.48 , pp. 183-185
    • Tang, C.W.1
  • 30
    • 24344458529 scopus 로고    scopus 로고
    • High-efficiency photovoltaic devices based on annealed poly(3-hexylthiophene) and 1-(3-methoxycarbonyl)-propyl-1-phenyl-(6
    • 083506 3
    • Reyes-Reyes, M.; Kim, K.; Carroll, D.L. High-efficiency photovoltaic devices based on annealed poly(3-hexylthiophene) and 1-(3-methoxycarbonyl)-propyl-1-phenyl-(6,6)c-61 blends. Appl. Phys. Lett. 2005, 87, 083506:1-083506:3.
    • (2005) Appl. Phys. Lett. , vol.87 , pp. 1-083506
    • Reyes-Reyes, M.1    Kim, K.2    Carroll, D.L.3
  • 31
    • 0141789891 scopus 로고    scopus 로고
    • Effect of local molecular structure on the chain-length dependence of the electronic properties of thiophene-based pi-conjugated systems
    • Frere, P.; Raimundo, J.M.; Blanchard, P.; Delaunay, J.; Richomme, P.; Sauvajol, J.L.; Orduna, J.; Garin, J.; Roncali, J. Effect of local molecular structure on the chain-length dependence of the electronic properties of thiophene-based pi-conjugated systems. J. Org. Chem. 2003, 68, 7254-7265.
    • (2003) J. Org. Chem. , vol.68 , pp. 7254-7265
    • Frere, P.1    Raimundo, J.M.2    Blanchard, P.3    Delaunay, J.4    Richomme, P.5    Sauvajol, J.L.6    Orduna, J.7    Garin, J.8    Roncali, J.9
  • 32
    • 33644945010 scopus 로고    scopus 로고
    • Triphenylaminethienylenevinylene hybrid systems with internal charge transfer as donor materials for heterojunction solar cells
    • Roquet, S.; Cravino, A.; Leriche, P.; Aleveque, O.; Frere, P.; Roncali, J. Triphenylaminethienylenevinylene hybrid systems with internal charge transfer as donor materials for heterojunction solar cells. J. Am. Chem. Soc. 2006, 128, 3459-3466.
    • (2006) J. Am. Chem. Soc. , vol.128 , pp. 3459-3466
    • Roquet, S.1    Cravino, A.2    Leriche, P.3    Aleveque, O.4    Frere, P.5    Roncali, J.6
  • 34
    • 37249075009 scopus 로고    scopus 로고
    • Efficiency potential of organic bulk heterojunction solar cells
    • Minnaert, B.; Burgelman, M. Efficiency potential of organic bulk heterojunction solar cells. Prog. Photovoltaics 2007, 15, 741-748.
    • (2007) Prog. Photovoltaics , vol.15 , pp. 741-748
    • Minnaert, B.1    Burgelman, M.2
  • 36
    • 23644434419 scopus 로고    scopus 로고
    • Flexible conjugated polymer-based plastic solar cells: From basics to applications
    • Dennler, G.; Sariciftci, N.S. Flexible conjugated polymer-based plastic solar cells: From basics to applications. Proc. IEEE 2005, 93, 1429-1439.
    • (2005) Proc. IEEE , vol.93 , pp. 1429-1439
    • Dennler, G.1    Sariciftci, N.S.2
  • 37
    • 10644228400 scopus 로고    scopus 로고
    • Photovoltaic action of conjugated polymer/fullerene bulk heterojunction solar cells using novel ppe-ppv copolymers
    • Hoppe, H.; Egbe, D.A.M.; Muhlbacher, D.; Sariciftci, N.S. Photovoltaic action of conjugated polymer/fullerene bulk heterojunction solar cells using novel ppe-ppv copolymers. J. Mater. Chem. 2004, 14, 3462-3467.
    • (2004) J. Mater. Chem. , vol.14 , pp. 3462-3467
    • Hoppe, H.1    Egbe, D.A.M.2    Muhlbacher, D.3    Sariciftci, N.S.4
  • 38
    • 1642635074 scopus 로고    scopus 로고
    • Correlation between oxidation potential and open-circuit voltage of composite solar cells based on blends of polythiophenes/fullerene derivative
    • Gadisa, A.; Svensson, M.; Andersson, M.R.; Inganas, O. Correlation between oxidation potential and open-circuit voltage of composite solar cells based on blends of polythiophenes/fullerene derivative. Appl. Phys. Lett. 2004, 84, 1609-1611.
    • (2004) Appl. Phys. Lett. , vol.84 , pp. 1609-1611
    • Gadisa, A.1    Svensson, M.2    Andersson, M.R.3    Inganas, O.4
  • 39
    • 33847797254 scopus 로고    scopus 로고
    • Increasing the open circuit voltage of bulk-heterojunction solar cells by raising the lumo level of the acceptor
    • Kooistra, F.B.; Knol, J.; Kastenberg, F.; Popescu, L.M.; Verhees, W.J.H.; Kroon, J.M.; Hummelen, J.C. Increasing the open circuit voltage of bulk-heterojunction solar cells by raising the lumo level of the acceptor. Org. Lett. 2007, 9, 551-554.
    • (2007) Org. Lett. , vol.9 , pp. 551-554
    • Kooistra, F.B.1    Knol, J.2    Kastenberg, F.3    Popescu, L.M.4    Verhees, W.J.H.5    Kroon, J.M.6    Hummelen, J.C.7
  • 41
    • 47249146849 scopus 로고    scopus 로고
    • Tuning the lumo level of the acceptor to increase the open-circuit voltage of polymer-fullerene solar cells: A quantum chemical study
    • Morvillo, P.; Bobeico, E. Tuning the lumo level of the acceptor to increase the open-circuit voltage of polymer-fullerene solar cells: A quantum chemical study. Solar Energy Mater. Solar Cells 2008, 92, 1192-1198.
    • (2008) Solar Energy Mater. Solar Cells , vol.92 , pp. 1192-1198
    • Morvillo, P.1    Bobeico, E.2
  • 42
    • 0345377522 scopus 로고    scopus 로고
    • Cathode dependence of the open-circuit voltage of polymer: Fullerene bulk heterojunction solar cells
    • Mihailetchi, V.D.; Blom, P.W.M.; Hummelen, J.C.; Rispens, M.T. Cathode dependence of the open-circuit voltage of polymer: Fullerene bulk heterojunction solar cells. J. Appl. Phys. 2003, 94, 6849-6854.
    • (2003) J. Appl. Phys. , vol.94 , pp. 6849-6854
    • Mihailetchi, V.D.1    Blom, P.W.M.2    Hummelen, J.C.3    Rispens, M.T.4
  • 43
    • 29944439716 scopus 로고    scopus 로고
    • International Standard, IEC 60904-3, Photovoltaic Devices-Part 3: Measurement Principles for Terrestrial Photovoltaic (PV) Solar Devices with Reference Spectral Irradiance Data, 2nd ed.; International Electrotechnical Commission: Geneva, Switzerland
    • International Electrotechnical Commission. International Standard, IEC 60904-3, Photovoltaic Devices-Part 3: Measurement Principles for Terrestrial Photovoltaic (PV) Solar Devices with Reference Spectral Irradiance Data, 2nd ed.; International Electrotechnical Commission: Geneva, Switzerland, 2008.
    • (2008) International Electrotechnical Commission
  • 44
    • 9544247754 scopus 로고    scopus 로고
    • Optimal energy offsets for organic solar cells containing a donor/acceptor pair
    • Sun, S.S. Optimal energy offsets for organic solar cells containing a donor/acceptor pair. Solar Energy Mater. Solar Cells 2005, 85, 261-267.
    • (2005) Solar Energy Mater. Solar Cells , vol.85 , pp. 261-267
    • Sun, S.S.1
  • 45
    • 0037389306 scopus 로고    scopus 로고
    • Small molecular weight organic thin-film photodetectors and solar cells
    • Peumans, P.; Yakimov, A.; Forrest, S.R. Small molecular weight organic thin-film photodetectors and solar cells. J. Appl. Phys. 2003, 93, 3693-3723.
    • (2003) J. Appl. Phys. , vol.93 , pp. 3693-3723
    • Peumans, P.1    Yakimov, A.2    Forrest, S.R.3
  • 46
    • 56349141061 scopus 로고    scopus 로고
    • Small-molecule solar cells-status and perspectives
    • doi:10.1088/0957-4484/19/42/424001
    • Riede, M.; Mueller, T.; Tress, W.; Schueppel, R.; Leo, K. Small-molecule solar cells-status and perspectives. Nanotechnology 2008, 19, doi:10.1088/0957-4484/19/42/424001.
    • (2008) Nanotechnology , pp. 19
    • Riede, M.1    Mueller, T.2    Tress, W.3    Schueppel, R.4    Leo, K.5
  • 47
    • 34250882186 scopus 로고    scopus 로고
    • Empirical study of the characteristics of current-state organic bulk heterojunction solar cells
    • Minnaert, B.; Burgelman, M. Empirical study of the characteristics of current-state organic bulk heterojunction solar cells. Eur. Phys. J. Appl. Phys. 2007, 38, 111-114.
    • (2007) Eur. Phys. J. Appl. Phys. , vol.38 , pp. 111-114
    • Minnaert, B.1    Burgelman, M.2
  • 48
    • 17244379019 scopus 로고    scopus 로고
    • The unusual effect of bandgap lowering by c-60 on a conjugated polymer
    • Sonmez, G.; Shen, C.K.F.; Rubin, Y.; Wudl, F. The unusual effect of bandgap lowering by c-60 on a conjugated polymer. Advan. Mater. 2005, 17, 897-900.
    • (2005) Advan. Mater. , vol.17 , pp. 897-900
    • Sonmez, G.1    Shen, C.K.F.2    Rubin, Y.3    Wudl, F.4
  • 49
    • 49449095269 scopus 로고    scopus 로고
    • Small bandgap polymers for organic solar cells (polymer material development in the last 5 years)
    • Kroon, R.; Lenes, M.; Hummelen, J.C.; Blom, P.W.M.; De Boer, B. Small bandgap polymers for organic solar cells (polymer material development in the last 5 years). Polym. Rev. 2008, 48, 531-582.
    • (2008) Polym. Rev. , vol.48 , pp. 531-582
    • Kroon, R.1    Lenes, M.2    Hummelen, J.C.3    Blom, P.W.M.4    De Boer, B.5
  • 50
    • 33749534699 scopus 로고    scopus 로고
    • Soluble narrow band gap and blue propylenedioxythiophene-cyanovinylene polymers as multifunctional materials for photovoltaic and electrochromic applications
    • Thompson, B.C.; Kim, Y.-G.; McCarley, T.D.; Reynolds, J.R. Soluble narrow band gap and blue propylenedioxythiophene-cyanovinylene polymers as multifunctional materials for photovoltaic and electrochromic applications. J. Am. Chem. Soc. 2006, 128, 12714-12725.
    • (2006) J. Am. Chem. Soc. , vol.128 , pp. 12714-12725
    • Thompson, B.C.1    Kim, Y.-G.2    McCarley, T.D.3    Reynolds, J.R.4
  • 51
    • 56449105933 scopus 로고    scopus 로고
    • Narrow energy gap polymers with absorptions up to 1200nm and their photovoltaic properties
    • Yi, H.N.; Johnson, R.G.; Iraqi, A.; Mohamad, D.; Royce, R.; Lidzey, D.G. Narrow energy gap polymers with absorptions up to 1200nm and their photovoltaic properties. Macromol. Rapid Commun. 2008, 29, 1804-1809.
    • (2008) Macromol. Rapid Commun. , vol.29 , pp. 1804-1809
    • Yi, H.N.1    Johnson, R.G.2    Iraqi, A.3    Mohamad, D.4    Royce, R.5    Lidzey, D.G.6
  • 53
    • 0038662042 scopus 로고    scopus 로고
    • Organic photovoltaic materials and devices
    • Nunzi, J.M. Organic photovoltaic materials and devices. C. R. Phys. 2002, 3, 523-542.
    • (2002) C. R. Phys. , vol.3 , pp. 523-542
    • Nunzi, J.M.1
  • 54
    • 77749327531 scopus 로고    scopus 로고
    • Controlled current matching in small molecule organic tandem solar cells using doped spacer layers
    • 044503 6
    • Schueppel, R.; Timmreck, R.; Allinger, N.; Mueller, T.; Furno, M.; Uhrich, C.; Leo, K.; Riede, M. Controlled current matching in small molecule organic tandem solar cells using doped spacer layers. J. Appl. Phys. 2010, 107, 044503:1-044503:6.
    • (2010) J. Appl. Phys , vol.107 , pp. 1-044503
    • Schueppel, R.1    Timmreck, R.2    Allinger, N.3    Mueller, T.4    Furno, M.5    Uhrich, C.6    Leo, K.7    Riede, M.8


* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.