Next-Generation. Organic Solar Cell Technology. and Market Forecast

Transcription

1 Next-Generation Organic Solar Cell Technology and Market Forecast Feb 2010

2 Next-Generation Organic Solar Cell Technology and Market Forecast Feb 2010 Displaybank Co., Ltd. 8F 810, Yatap Leaders Bldg Yatap-dong, Bundang-gu, Seongnam-si, Gyeonggi-do, Korea Phone: (82) , Fax: (82)

3 Copyright 2010 Displaybank Co., Ltd. All rights reserved. No material contained in this report may be reproduced in whole or in part without the express written permission of Displaybank Co., Ltd. This report is intended for the sole and exclusive use of the original purchaser and may not be distributed or transferred in any form to any other person or entity. Displaybank Co., Ltd. provides the information in this report for informational purposes only and does not grant any express or implied warranty, guaranty, or representation concerning the information contained in this report, its merchantability, or its fitness for a particular purpose or function. Any reference to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by Displaybank Co., Ltd. Neither Displaybank nor any of its affiliates shall be liable to you or any third party in damages of whatever kind that may result from any reliance on (or use of) any information contained in this report. By receiving this report, you acknowledge that any reliance on information contained in this report shall be at your sole risk and that no representations have been made to you that are inconsistent with the foregoing.

4 1. Introduction <Table of Contents> 1.1. Overview 1.2. Need for Organic Solar Cell 1.3. Potential of Organic Solar Cell 2. Organic Solar Cell Technology Trend 2.1. History of Organic Solar Cell 2.2. Operating Principal of Organic Solar Cell Photoelectric Conversion Effect Solar Cell Effect 2.3. Type of Organic Solar Cell Polymer Donor-PCBM Acceptor Type Polymer Donor-Non-PCBM Acceptor Type Polymer Donor-Polymer Acceptor Type Polymer Donor-Inorganic Acceptor Type 2.4. Organic Solar Cell Application Field 3. Organic Solar Cell Material Development Trend 3.1. Photoactive Layer Material Organic Semiconductor Material for Donor (p-type) Organic Semiconductor Material for Acceptor (n-type) Inorganic Acceptor (n-type) Material 3.2. Substrate and Transparent Electrode Type of Flexible Substrate Material Performance Requirement of Flexible Substrate Material Transparent Electrode Material for Flexible Substrate 4. Organic Solar Cell Device and Module Technology 4.1. Organic Solar Cell Device Regular Structure

5 Tandem Structure Inverted Structure 4.2. Organic Solar Cell Device Evaluation Organic Solar Cell Efficiency Measurement Technology Energy Conversion Efficiency Measurement Error Organic Solar Cell Device Lifetime Measurement Technology 4.3. Organic Solar Cell Module Technology 5. Organic Solar Cell Printing Process Technology and Development Status 5.1. Screen Printing Based Organic Solar Cell 5.2. Pad(gravure offset) printing 5.3. Ink-jet Printing Based Organic Solar Cell 5.4. Aerosol Jet Printing Based Organic Solar Cell 5.5. Spray printing 5.6. Roll-to-Roll Printing Based Organic Solar Cell 5.7. Micro-contacting printing 5.8. Brush painting 6. Organic Solar Cell Patent Analysis 6.1. Global Patent Trend 6.2. Korea Patent Trend 6.3. Key Patent Analysis 7. Organic Solar Cell R&D Trend 7.1. Support Policy of Each Country Organic Solar Cell Field Support Status of Major Global Countries Korea s Organic Solar Cell Field Support Status 7.2. R&D Trend of Major Global Countries Konarka (US) Plextronics (US) Solarmer Energy (US) Heliatek (Germany)

6 Mitsubishi Chemicals (Japan) Teijin DuPont Fims (Japan) Toray (Japan) Sumitomo Chemicals (Japan) 7.3. Korea R&D Trend Kolon KNP Energy GIST KRICT KIST KIMM Konkuk University Others 8. Organic Solar Cell Market Forecast 8.1. OPV Market Forecast 8.2. OPV Market Forecast by Application Field 8.3. OPV Price Forecast by Application Field 8.4. Market Size Forecast by Application Field (Revenue Based) 9. Conclusion 10. Index Tables Figures References

7 1.2. Need for Organic Solar Cell The use of fossil energy has radically increased in the 21 st century joined with advancements of developing countries. Here, the fossil energy refers to an energy source which is created by dead bodies of animals and plants after a long period of time. It includes fossil fuels such as petroleum and coal. It was imperative for the fossil energy use to increase in order to obtain massive power through industrialization. However, this fossil energy requires a long period of time for creation. Its use rapidly increases compared to the rate of creation that it faces exhaustion in the next several centuries. If it does exhaust, the world s scientific civilization, which had been growing based on the fossil energy, must come to a halt and not only the energy, but the survival of mankind is predicted to be risk. Hence, the mankind must focus on developing a new renewable energy source in this century. The solar cell market has been showing nearly CAGR 40% for the past decade. Such super fast growth is closely connected to the price of crude oil, which is the world s most widely used fossil fuel. As shown in figure 3, R&D activities regarding in organic solar cell such as Si solar cell began in the 70s as the first oil shock occurred. The solar cell market expanded explosively in the 2000s as the crude oil price, which maintained a stable level since the end of 80s, sky-rocketed. In addition, the price dropped in the end of 2008 due to the global economic recession to result in a steady solar cell market in 2009 for the first time after it was commercialized. The increasing rate of crude oil price is expected to continue for a while since the fossil fuel is at risk of exhaustion by the end of the century. The solar cell R&D is inevitable for the mankind as the energy is renewed infinitely and as the issue of CO2 discharge regulation emerges on the surface based on the understanding of its role in the global warming.

8 Figure 4. Best Cell Efficiency of Thin Film Solar Cell However, the low energy conversion still remains to be a shortcoming of organic solar cell. Figure 4 illustrates thin film solar cell s device efficiency change by year. In comparison to CIGS, a-poly Si, and DSSC, the device efficiency is found to be 1/2~1/4. Though, the organic solar cell device efficiency has been showing increases every year since 2000 through a new donor-acceptor material s design and synthesis that it is expected to reach about 10% which is equivalent to DSSC. In addition, makers must enhance photoactive layer materials stability and develop materials to maintain a steady morphology in order to expand the device lifetime. They must first develop flexible substrates with outstanding barrier properties and encapsulation/passivation technologies. Fortunately, the organic solar cell has many similarities with OLED that the issues of flexible substrates and encapsulation/passivation technologies may be resolved through an

9 import of OLED result. Lastly, makers must bring down the manufacturing cost to $0.5/Wp by developing roll-to-roll continuous printing process. Inorganic solar cells targeted manufacturing cost is about $1/Wp and this is converted to electricity cost for homes. When converting this to a manufacturing cost per unit area based on 5% organic solar cell, about 30W/1m2 is generated at aperture 60%. This means the area of 1m2 must be manufactured at $30. Surely, half of the solar cell cost is installation expense that, in reality, the area of 1m2 needs to be manufactured with $15. Considering the fact that current ITO transparent glass substrate costs about $15 per m2, this is very challenging. Hence, it is important to develop flexible substrates with excellent barrier properties. Figure 5. Key Technology and Requirement for Flexible Organic solar cell Commercialization (KRICT)

10 2. Organic solar cell Technology Trend 2.1. History of Organic Solar Cell The organic solar cell using conjugated system based organic semiconductor materials began to show a rise in its potential as Eastman Kodak s C.W. Tang PhD presented a device in At that time, Tang accomplished about 1% energy conversion efficiency under AM 1.5G light source by forming a bilayer through a vacuum deposition of CuPc and perylene dimmide based p-type and n-type organic semiconductor material between ITO transparent electrode and Al cathode. This result was an innovative advancement. The photoelectric conversion efficiency has increased to about 7.9% now after about 20 years based on an improvement through organic semiconductor s p-n junction. Unofficially, even higher energy conversion efficiencies allegedly wait to be announced. The organic solar cell is divided into a vacuum deposition based device and solution process based device according to the device manufacturing process. In terms of OLED, a vacuum deposition based device was commercialized first. On the other hand, the organic solar cell s solution process based device forms a bulk heterojunction between a donor and acceptor well that its property is known to be better. Hence, it is expected to realize low-cost/large-area productions through printing processes. Next, we will take a look at improvement steps of bulk heterojunction organic solar cell using a polymer donor, which enables low-cost/massive production through the solution process, and a PCBM based acceptor (figure 6).

11 Figure 1. Efficiency Improvement Status of Organic solar cell Unit Device (KRICT, 2009) In 2003, J.C. Hummelen Group has reported 0.2% photoelectric conversion efficiency by combining P3HT with PCBM. At that time, PPV [poly(phenylenevinylene)] based donor materials were widely used that the combination with PCBM was done in 1:4. This result was improved to 3.5% in the same year by F. Padingger Group as they changed the combination ratio of P3HT to PCBM to 1:1 and operated photoactive layer annealing at 75 C for 4 minutes. Thereafter, various groups such as C.J. Brabec 1, D.A. Carroll 2, Y. Yang 3, D.D.C. Bradley 4, G.C. Bazan 5, and A.J. Heeger have enhanced the device efficiency through methods regulating either heat treatment or solvent vaporization. As a result, over 5% efficiency was reported in In particular, Konarka was officially approved of 5.21% efficiency with cm2 unit device by NREL in 2006 through using P3HT:PCBM photoactive layer. In addition, GIST s Professor Gwang-hee Lee team and UCSB s A.J. He6eger group reported that they have manufactured a tandem structure device based on solution process by using a new low-bandgap donor (PCPDTBT) and have accomplished 6.5% photoelectric conversion efficiency.

12 3.5 (80) ITO/PEDOT:PSS (100) P3HT:PCBM ( ) LiF/Al (0.6/60) Spin Cast (DCB) 75 C/4min (100) ITO/PEDOT:PSS (30) P3HT:PCBM (1:2,200) LiF/Al (0.6/100) Spin Cast (CB) 100 C/5min (100) 0.28 ITO/PEDOT:PSS (50) P3HT:PCBM (1:1, 70-80) LiF/Al (0.8/100) Spin Cast (CB) 100 C/30min (100) ITO/PEDOT:PSS (38) P3HT:PCBM (1:1, 225) LiF/Al (0.7/100) Spin Cast (DCB) 80 C/4min (100) - ITO/PEDOT:PSS P3HT:PCBM (1:1, 300) LiF/Al Spin Cast (DCB) 110 C/4min (100) 0.05 ITO P3HT:PCBM Al Spin Cast (100) - ITO/PEDOT:PSS (30) P3HT:PCBM (1:1, 63) Ca/Al (25/80) Spin Cast (DCB) 110 C/10min (100) ITO/PEDOT:PSS (50) P3HT:PCBM (1:1, 200) LiF/Al (0.7/100) Spin Cast (DCB) 80 C/4min (100) 0.11 ITO/PEDOT:PSS (25) P3HT:PCBM (1:1, 210) Ca/Al (25/80) Spin Cast (DCB) 110 C/10min (80) 0.19 ITO/PEDOT:PSS P3HT:PCBM (1:0.8) LiF/Al (3/100) Spin Cast (CB) 155 C/5min (80) ITO/PEDOT:PSS (40) P3HT:PCBM (1:0.8) Al (100) Spin Cast (CB) 150 C/30min

13 Polymer Donor-Inorganic Acceptor Type Since 2001, inorganic materials other than C60, PCBM, or n-type polymer materials began to be applied in organic solar cell s acceptor materials. The device was manufactured by making TiO2, which was widely used in the conventional DSSC, and other n-type inorganic semiconductor materials into particles or nano-bar shape and combining them with polymer donor materials (figure 4). These inorganic materials have excellent electron affinity and high electron mobility that they are expected to have advantages in organic solar cell applications, but there has not yet been a device with higher efficiency than the PCBM reported. Though, a device with improved efficiency is expected to be manufactured through a combination with a donor which has a proper HOMO/LUMO level and by reducing an interface resistance between the polymer donor and inorganic materials. Therefore, this clearly is one of critical R&D fields in a long run. Figure 11. CdSe Nano Particle TEM Image by Aspect Ratio (a) 7nm:7nm, (b) 7nm:30nm, (c) 7nm:60nm (A.P. Alivisatos et al, Science, 295, 2425 (2002)) Of this, let s take a closer look at the organic solar cell which uses CdSe nano particles as acceptor. In 2002, U.C. Berkeley s A.P. Alivisatos group has reported synthesis of CdSe nano particles with various aspect ratios (figure 11). These nano particles are used to manufacture organic solar cell devices through a combination with

14 P3HT donor. As a result, the nano particle based device s efficiency was very low, but a device based on CdSe nanoline with 7nm diameter and 60nm length is found to have about 1.7% energy conversion efficiency as it showed 5.7mA/cm2 short circuit current under AM 1.5G 1sun (figure 12 (c)).

15 2.4. Organic Solar Cell Application Field The organic solar cell has not yet been commercialized as of We will summarize its application field by utilizing reports from Konarka and Plextronics. First, Konarka limits the application in 4 fields; 1) personal mobile phone charger, 2) small home electronics and mobile electronics attachment, 3) BIPV such as building s exterior wall, window, or blinder, and 4) power generation. Konarka predicts the market may be pioneered in each of these fields according to the module efficiency. In particular, the company predicts that the organic solar cell will be initially applied for special uses such as military market first due to low efficiency and high power generation unit cost. In reality, R&D activities proceed in relation to this. Table 5. Strengths and Weaknesses of Organic Solar Cell Strength Weakness - convenient design/synthesis of new materials - simple device structure and solution process - enables flexible substrate based roll-to-roll process - utilizes the conventional production facilities - integrated application of the conventional organic electronic device technology - realizes transparent device - low efficiency as of now - vacuum deposition process of cathode electrode - complex morphology of photoactive layer As shown in the above, the low-cost organic solar cell may be produced due to its strengths in material and process (table 5). Though, its application in power generation field appears rather difficult due to the low device efficiency. Hence, it is expected to be utilized for mobile electronic device charger or military use in the early commercialization. Konarka selects three organic solar cell application fields: mobile-use, exterior-use, and interior-use. The company predicts the time for market entry in each application field (table 6). It is noteworthy that the company intends to commercialize 4W and 8W flexible organic solar cell module in 2H 08 and apply product to each application by 2012.

16 Richard Hess, CEO at Konarka, said that the company will first focus in niche markets such as umbrella and tent until the conversion efficiency improves from 7% to10%. He also added that he expects to see the product compete against the conventional solar cells in terms of cost once it reaches certain level. Figure 16. Chemical Structure of Organic solar cell Donor and Acceptor Materials As shown in figure 16, several donor and acceptor materials are being reported, but none of them allegedly obtains over 3% efficiency except for P3HT/PCBM or PCPDTBT/PCBM.

17 Organic Semiconductor Material for Acceptor (n-type) The most widely applied acceptor material in the current organic solar cell is the PCBM. It is a methanofullerene substituted in C60 or C70 and was first synthesized by F. Wudl group in 1995 (figure 31). This material was originally developed for anticancer drug and has been used for the organic solar cell acceptor in most references since its first application till now. The synthesized PCBM has two isomers; one is a [5,6] isomer substituted in a junction between 5-angle ring and 6- angle ring of fullerene and the other is a [6,6] isomer substituted in a junction in between two 6-angle rings. The [5,6] isomer, which has a kinetic advantage in initial reaction, allegedly is synthesized first and is transformed to the [6,6] isomer which is thermodynamically stable. Here, only the [6,6] isomer is used for the organic solar cell acceptor that an additional refining process is required in order to realize a device performance with better efficiency. Figure 31. Synthesis of PCBM The actual organic thin film solar cell device is manufactured by combining and coating more than two ingredients that the ratio and processing condition of each ingredient is extremely important. Nelson et al. have conducted a test in searching for an optimum composition ratio in P3HT/PCBM binary system and observed an optimum efficiency when the P3HT weight ratio was about 50~60%. In addition, the efficiency radically rises after a heat treatment at 140 and explained the phenomenon had occurred as PCBM crystal was produced after a phase separation. As illustrated in figure 32, about 90nm thickness

18 showed the best efficiency when P3HT: PCBM ratio was 60%, whereas devices with 140nm and 250nm thicknesses showed slightly better efficiencies when the ratio was 50%. Figure 50. Inverted Device Structure and Lamination Process Using Ag Nanowire as Transparent Electrode Figure 52. (a) Ag nanowire Transparent (b) Current Voltage Property of Inverted Device Upon Presence of Cs2CO3

19 Source: Sol. Energy Mater. Sol. Cells. 93 (2009) Figure 52. Illustration of the screen printing process (above) and examples of a laboratory screen printer (bottom left) and an industrial screen printer (bottom right). R&D results regarding screen printing method based large-area organic solar cell module production were also reported. In 2004, F. C. Krebs group had formed MEH-PPV (with 100,000 g/mol(pdi=2.0) molecular volume) thin film in screen printing method to manufacture a large-area module and evaluated its property. The group used ITO coated PET (200um thickness) as a substrate and formed ITO patterns through etching. In order to collect current generated by the light, electrical contacts are formed around active area edges. Here, Ag paste was printed in screen printing method and hardened at 150. The MEH- PPV solution (chlorobenzene solvent) was screen printed on the upper ITO pattern, C60 was proceeded with vacuum deposition, and Al electrode was formed to manufacture 100cm2 large-area module (PET/ITO/MEH-PPV/C 60 /Al). The manufacture module recorded 4.6x10-3 % (Voc=0.73V, Isc=20)IT 2 ) efficiency under AM 1.5(100 mw/cm 2 ) condition. An office laminator was used to laminate the PET foil in order to shield the manufactured module from the air and the lifetime (Isc decreasing rate) was evaluated.

20 6. Organic Solar Cell Patent Analysis 6.1. Global Patent Trend In April 2009, Japanese Patent Office has announced the result of patent (applied in 2000~2006) analysis by applicant s nationality (figure 70). Japan s patent application is predominant in the crystalline Si solar cell field, whereas Europe s patent application is relatively predominant in the organic solar cell field. Of about 7,980 solar cell related patents, Japanese makers accounted for 68.4% and far preceded Europe (15.3%) and US (10.6%). Japanese applicants recorded over 70% in the Si thin film solar cell field and over 50% in both crystalline compound semiconductor solar cell and thin film compound semiconductor solar cell fields. However, Japanese applicants accounted for 46% in the organic semiconductor based solar cell field to show only a slight predominance over US (29%) and Europe (19%). Therefore, it appears that not only Japan, but also U.S. and Europe conduct R&D in the organic solar cell field actively. In this analysis, the DSSC field was excluded. Figure 96. Number of Solar Cell Related Patent by Applicant s Nationality ( , Japanese Patent Office)

21 7. Organic Solar Cell R&D Trend The Si solar cell which has high manufacturing process expenses show delayed commercialization due to difficulties in overcoming its manufacturing cost limitation as Si wafer raw material supply shortage intensifies. On the other hand, the conjugated system organic/polymer material based organic solar cell is expected to reduce the manufacturing cost through new processes such as printing process. Therefore, the commercialization seems only possible by maximizing the energy conversion efficiency through a development of new conjugation system organic materials with reduced bandgap Support Policy of Each Country Organic Solar Cell Field Support Status of Major Global Countries As of 2007, US based Konarka, Holland based DPI (Dutch Polymer Institute), and other academies in US, Europe, and Japan proceeded with R&D activities focused in Lab level unit device. In March 2007, US DOE started a new solar cell development related business of which the R&D cost was $51,600,000 and 13 companies participated. Of this, Konarka planned a dye-sensitized organic solar cell inclusive organic solar cell R&D for 3 years with $1,200,000. Through this program, Konarka targets to accomplish less than $0.1/kWh LCOE (levelized cost of energy) and 1,000~3,000MW production capacity by Table 11 illustrates the organic solar cell support status of major global countries. Nearly all R&D groups are in process of manufacturing devices using the same materials (P3HT as donors and PCBM as acceptors). These materials have not been changed since In particular, no conjugated organic material with better property emerged for an acceptor since the PCBM began to be used by professor A. G. Heeger in 1995 that it is imperative to develop new materials with high conversion efficiency.

22 Solarmer Energy (US) Solarmer was established after a spin-off from UCLA s Y. Yang group in March 2006 and develops flexible and transparent plastic solar cell panels. Recently, the company has developed a new low bandgap donor material through a joint R&D with Luping Yu group from U of Chicago. The company presents the world s top level Organic Solar Cell one after another using this. In December 2009, Solarmer has announced its development of a unit device (aperture: 0.047cm2) with 7.9% efficiency at US MRS meeting. This device recorded a high fill factor at 70.87%. Keith Energy from NREL has commented that this cell and module showed the best efficiency out of all Organic Solar Cell that have been measured thus far. Such comment adds to the optimism of organic solar cell commercialization. Moreover, the company presented Newport approved large-area (202 cm2) module which had accomplished 3.9% efficiency through 185 ma, Isc, 8.6 V, Voc, 49.1% fill factor (figure 80). Figure 2. Solarmer s Large-Area (202 cm2) Organic solar cell Module and Device Property

23 8.4. Market Size Forecast by Application Field (Revenue Based) The revenue based organic solar cell market by field is illustrated in the figure below. The mobile field is expected to reach $172M, the BIPV field will reach $93.5M, the military field will reach $38.35M, and the power generation facility field will reach $31.5M by Figure 117. Revenue by application Revenue (Mil.$) Conventional Solar panel Mobile application BIPV Military application Table 18. Revenue by application Conventional Solar panel Mobile application BIPV Military application

24 10. Index Tables Table 1. P3AT/PCBM Blend Organic solar cell Table 2. P3AT/non-PCBM fullerene Blend Organic solar cell Table 3. P3AT/Polymer Blend Organic solar cell Table 4. organic/inorganic hybrid organic solar cell Table 5. Strengths and Weaknesses of Organic solar cell Table 6. Required Property and Use of Applicable Organic solar cell by Field Table 7. Thermal Property Comparison of Poly(3-alkylthiophene)s Table 8. Commercially Purchasable P3HT Type based regioregularity and Molecular Volume Analysis Table 9. Performances of inkjet printed(ij) and doctor bladed(db) devices. Table 10. IPC Classification based Annual Number of Patent Comparison ( ) Table 11. Korea Patent IPC Classification based Annual Number of Patent Comparison Table 12. Organic solar cell Development Status of Major Countries Table 13. Korean Government s Organic solar cell Related Support Status Table 14. OPV Production and Market Size Forecast Table 15. OPV Production Capacity Forecast by Application Field (MW) Table 16. OPV Market Share Forecast by Application Field Table 17. OPV Price Forecast by Application Field Table 18. Revenue by application

25 10.2. Figures Figure 1. PV Installation Area to Replace Overall Energy Consumption in US (N. Lewis, Caltech) Figure 2. Monthly Average Electricity Consumption and PV Economy Analysis (Daewoo Securities Research Center, 2008) Figure 3. Crude Oil Prices (2008 Dollars, WTRG Economics) Figure 4. Best Cell Efficiency of Thin Film Solar Cell Figure 5. Key Technology and Requirement for Flexible Organic solar cell Business (KRICT) Figure 6. Organic solar cell Unit Device Efficiency Improvement Status (KRICT, 2009) Figure 7. 4 Steps of Photoelectric Conversion Effect and Effciency in Each Step [P. Peumans and S.R. Forrest et al, Chem. Phys. Lett., 398, 27 (2004)] Figure 8. Solar Cell Current-Voltage Property Curve Figure 9. Comparison of Voc Change According to (a) Change in Acceptor LUMO Level (b) Change in Work Function of Cathode [Brabec, C.J. et al, Adv. Func. Mater., 11, 374, (2001)] Figure 10. Representative Low Bandgap Donor Material Structure 오 Figure 11. CdSe Nano Particle TEM Image by Aspect Ratio (a) 7nm:7nm, (b) 7nm:30nm, (c) 7nm:60nm (A.P. Alivisatos et al, Science, 295, 2425 (2002) Figure 12. (a) P3HT/CdSe Organic/Inorganic Hybrid Solar Cell Device Structure, (b) CdSe Nano Particle Shape based Photoactive Layer s External Quantum Efficiency (c) Organic/Inorganic Hybrid Solar Cell Device Current-Voltage Property Using CdSe with 7nm:60nm aspect ratio [Huynh, W.U., Dittmer, J.J., Alivisatos, A.P., Science, 295, 2425 (2002)] Figure 13. Hyperbranched CdSe Particle Based Organic/Inorganic Hybrid Solar Cell (a) Device Structure, (b) Current-Voltage Property, (c) TEM Image [Gur, I., Fromer, N.A., Chen, C.-P., Kanaras, A.G., Alivisatos, A.P., Nano Lett., 7, 409 (2007)] Figure 14. Predicted Application Field of Flexible Organic solar cell (Konarka) Figure 15. Organic solar cell Application Field Predicted by Plextronics (Plextronics) Figure 16. Chemical Structure of Organic solar cell Donor and Acceptor Materials Figure 17. Representative Organic solar cell Donor Material Structure Figure 18. HOMO/LUMO Level Comparison of Donor, Acceptor,and Electrode Materials Figure 19. Coupling Regiochemistry Figure 20. a) Solor Cell IV Manufactured with Different P3HT (Efficiency 86%: 3.9%; 90%: 3.8%; 96%: 3.8% b) Change in Photoelectric Conversion Efficiency According to the Time of Solar Cell with Thermal Treatment at 150 [Frechet J.M. et al, J. Am. Chem. Soc., 130, (2008)] Figure 21. P3HT-Block-P3EHT Synthesis Method Figure 22. a) AFM and b) UV Absorption Spectirum of P3HT-Block-P3EHT (83:17) Figure 23. Result of Device Efficiency Improvement by Adding 1,8-octanedithiol to PCPDTBT/PCBM Blend Photoactive Layer Figure 24. NREL Approved Organic solar cell by Konarka Figure 25. PSBTBT:PC70BM Blend System Structure and Current-Voltage Property Figure 26. Device Performance Comparison Through PSBTBT Structure and Combination with

26 PC70BM by Molecular Volume Figure 27. 2,7-carbazole Based Copolymer Structure and HOMO/LUMO Level Figure 28. PCDTBT:PC70BM Blend Systen Device Structure and Material Energy Level Comparison Figure 29. a) PTB1 Fullerene Derivative s Chemical Structure, b) PTB2 Solution, Film, and PC61BM Blend s UV Spectrum Figure 30. (a) Solarmer s Improved PTB Donor Derivative Energy Structure (b) Energy Level Comparison Figure 31. PCBM s Sysnthesis Process Figure 32. Composition Ratio Based Device Photoelectric Conversion Efficiency (Open Symbol: 140 Pre-Heat Treatment; Filled Symbol: Post-Heat Treatment; Thickness:, 90 nm;, 140 nm;, 250 nm) Figure 33. Aceton Concentration Based Film Nanofibril Growth (a)-(d) UV Spectrum (e) Figure 34. Various C60 Derivative Structure and Abbrevation. Figure 35. NREL Approved 5.42% Organic solar cell (Plextronics) Figure 36. Bis-PCBM s Electro-chemical Property and Organic solar cell Property Through Combination with P3HT Figure 37. ZnO Acceptor Based Organic solar cell Module (F.C. Krebs) Figure 38. Optical Polymer Material s Chemical Structure Figure 39. Optical Polymer Material s Tg Comparison Figure 40. Plastic Substrate Material s Thermal, Mechanical, Optical, and Chemical Property Comparison Figure 41. Representative Organic solar cell Structure Figure 42. Regular Bulk Heterojunction Type Organic solar cell Device Structure Figure 43. Flexible Organic solar cell Module Structure (Konarka) Figure 44. P3HT:PCBM Blend Photoactive Layer s TEM Analysis Result and Simulation Based Pre- /Post-Annealing Morphology Change Figure 45. Hybrid Planar-mixed Molecular HJ Tandem Solar Cell Figure 46 Figure 47. Organic solar Cell of PSBTBT and P3HT Based Tandem Structure Figure 48. Organic solar cell Device with (a) Regular Structure and (b) Inverted Structure Figure 49. Inverted Organic solar cell Device and Current-Voltage Property Comparison Figure 50. Inverted Device Structure Using Ag nanowire as Transparent Electrode and Lamination Process Figure 51. (a) Ag Nanowire Transparent Electrode Transmittance and (b) Inverted Device Current- Voltage Property Upon Cs2CO3 Presence Figure 52. Solar Simulator s Light Source Comparison by Maker and Device Measurement Comparison Using the Same (KRICT) Figure 53. Konarka s Flexible Organic solar cell Device Lifetime Measurement Result (ECN) Figure 54. Konarka s Organic solar cell for Lifetime Measurement and Pre/Post-Measurement Device Property Comparison Figure 55. Plextronics Organic solar cell Lifetime Measurement Result Figure 56. p-i-n tandem Organic solar cell s Pre/Post-Lifetime Measurement Currnt-Voltage Property

27 Comparison (Heliatek) Figure 57. Module Manufactring Process Comparison between Thin Film Solar Cell, DSSC, and Organic solar cell (Kolon, 2009) Figure Series Connected Organic PV Module Structure and Series Connection Based Current- Voltage Curve Figure 59. Current-Voltage Curve of 5-Series Connected Organic PV Module Upon Au Bus Electrode Presence (KRICT) Figure 60. Organic solar cell Module Structure (Konarka) Figure 61. Pixel Shape Based Organic Solar Cell Efficiency Change Figure 62. Roll-to-Roll Continuous Printing Based Organic solar cell Manufacutirng Process and Module (Konarka) Figure 63. Thin Film Solar Cell s Predicted Power Generation Cost/W Comparison Figure 64. Required Viscosity Range by Printing Process Figure 65. Illustration of the screen printing process (above) and examples of a laboratory screen printer (bottom left) and an industrial screen printer (bottom right) Figure 66. Module design: 7 rows of 13 cells serial connected giving a total of 91 elements with an active area of 7.2 cm 2 per cell Figure 67. The structure and layer thickness of device. Figure 68. A process flow chart outlining all the steps employed in this process along with the process time starting with 200m of PET/ITO substrate that gave a final yield of 2124 completed modules. Figure 69. The final modules comprising screen printed layers, back lamination and crimped contacts (left) and all the 2,124 modules (right). Figure 70. The Solar Hat comprising hat, polymer solar cell, FM radio, ear plugs and neck strap (top left). Two large parasols were prepared for the festival each comprising 8 segments of cells connected in parallel. The eight individual segments on the parasol could be connected in series or parallel (top right and middle). Figure 71. VTT s PICO pilot printing facility containing two gravure printing units. Figure 72. Modified PEDOT:PSS roll-gravure printed in pilot printing machine. Figure 73. a) A schematic image of the R2R gravure coating process shows that the gravure roll is rotating in the opposite direction at the web. b) A photo of Mini-Labo test coater. Figure 74. (a) Schematic diagram of the printing process, (b) electromechanical engraved pattern, and (c) cross-sectional view of an electromechanical engraved cell. Figure 75. A photograph of pad printer(upper) and examples of pads (lower). Figure 76. The process of the pad printing cycle Figure 77. Chemical structures for the materials employed. Figure 78. Scheme of droplet dry process Figure 79. Schematic organic film formation(a) and flexible solar cell(b) by inkjet printing. Figure 80. J-V characteristics of inkjet printed devices with solvent system and RR of P3HT. Figure % Ink-Jet Printing Organic solar cell (KRICT) Figure 82. Aerosol-Jet Printing Based Organic solar cell Device and Series Connected Current-Voltage Property Figure 83. Schematical illustration of spray deposition apparatus

28 Figure 84. Ultrasonic sprayer schematic showing carrier gas directing ultrasonically formed droplets on to the substrate. Figure 85. Schematic illustration of the spray process. Figure 86. J-V curves of sprayed OSCs with different effective thicknesses of active layers. 오 Figure 87. IPCE curves of sprayed and spin coated OSCs (a) and J-V curves of sprayed and spin coated devices fabricated in air(b). Figure 88. R2R wet coating Method Based Flexible Organic solar cell and Current-Voltage Property 의 Figure 89. Rotogravure Printing Method and Current-Voltage Property of Device Manufactured by the Same. Figure 90. General procedures of micro contacting printing Figure 91. Surface patterning method used to generate C60 patterns by μcp and backfilling process. Figure 92. AFM topography and fluorescence image of MDMO-PPV:PCBM thin layer on patterned surface. Figure 93. P3HT, PEDOT:PSS and Ag patterns by μcp. Figure 94. Schematic diagram of the brush-painting process Figure 95. I-V curves of solar cells fabricated by spin coating and brush painting. Figure 96. Number of Solar Cell Related Patent by Applicant s Nationality ( , Japanese Patent Office) Figure 97. Organic Solar Cell Related Patent Market Share Analysis by Region ( ) Figure 98. Organic Solar Cell Related Patent Application by Year ( ) Figure 99. Number of Patent by Applicant ( ) Figure 100. P3HT:PCBM Based Organic Solar Cell Related Key Patent Figure 101. Solar Cell Efficiency Improvement Status (DOE, USA, 2006) Figure 102. Joint R&D Status of Global Organic Solar Cell Makers Figure 103. Konarka s NREL Approved Organic Solar Cell Current-Voltage Curve Figure 104. Plextronics NREL Approved Cell Current-Voltage Curve (Aug. 2008) Figure 105. Plextronics Organic Solar Cell Panel (15.2 X 15.2 cm2) Figure 106. Solarmer s Large-Area (202 cm2) Organic PV Module and Device Property Figure 107. Solarmer s Translucent Organic Solar Cell Device Structure and Device Sample Figure 108. Heliatek s Vaccuum Deposition Based Organic Solar Cell with p-i-n Structure Figure 109. Heliatek s Organic Solar Cell Accelerated Lifetime Measurement Figure 110. Conventional Organic PV Module and High Integrated Organic PV Module Comparison Figure 111. KIMM s Roll-to-Roll Continuous Production System Figure 112. OPV Production Forecast (MW) Figure 113. OPV Market Size (Revenue Based, Mil$) Figure 114. OPV Production Capacity Forecast by Application Field (MW) Figure 115. OPV Market Share Forecast by Application Field. Figure 116. OPV Price Forecast by Application Field Figure 117. Revenue by application