Electron Microscopy of Thin Film Inorganic and Organic Photovoltaic Materials

  • Aidan A. Taylor
  • Budhika G. MendisEmail author


Scanning and transmission electron microscopy have played an important role in the progress made by photovoltaic devices over the past two decades. With thin-film photovoltaic (PV) devices now accounting for more than 20 % of total PV sales, this chapter reviews the important insights into PV materials gleaned from electron microscopy.


Solar Cell Space Charge Region Organic Solar Cell Absorber Layer Atom Probe Tomography 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


  1. 1.
    Shockley W, Queisser HJ (1960) Detailed balance limit of efficiency of pn junction solar cells. J Appl Phys 32:510–519CrossRefGoogle Scholar
  2. 2.
    Green MA, Emery K, Hishikawa Y, Warta W, Dunlop ED (2013) Solar cell efficiency tables (version 41). Prog Photovolt Res Appl 21:1–11CrossRefGoogle Scholar
  3. 3.
    Henry CH (1980) Limiting efficiencies of ideal single and multiple energy gap terrestrial solar cells. J Appl Phys 51:4494CrossRefGoogle Scholar
  4. 4.
    Riordan C, Hulstrom R (1990) What is an air mass 1.5 spectrum. Photovolt Spec Conf 21:1085–1088CrossRefGoogle Scholar
  5. 5.
    Burgers AR, Eikelboom JA, Schoenecker A, Sinke WC (1996) Improved treatment of the strongly varying slope in fitting solar cell I-V curves. Photovolt Spec Conf 25:569–572Google Scholar
  6. 6.
    Hegedus SS, Shafarman WN (2004) Thin-film solar cells: device measurements and analysis. Prog Photovolt Res Appl 12:155–176CrossRefGoogle Scholar
  7. 7.
    Dhere RG, Duenow JN, Dehart CM, Li JV, Kuciauskas D, Gessert TA (2012) Development of substrate structure CdTe photovoltaic devices with performance exceeding 10%. Photovolt Spec Conf 38:003208–003211Google Scholar
  8. 8.
    Wu JJ, Wu HC, Zhao CZ (2012) CdTe solar cells on flexible metallic substrates. Adv Mater Res 535:2075–2078CrossRefGoogle Scholar
  9. 9.
    Cusano DA (1963) CdTe solar cells and photovoltaic heterojunctions in II-VI compounds. Solid State Electron 6:217–233CrossRefGoogle Scholar
  10. 10.
    Bonnet D, Rabenhorst H (1972) New results on the development of a thin film p-CdTe- nCdS heterojunction solar cell. Photovolt Spec Conf 9:129–132Google Scholar
  11. 11.
    Tyan Y-S, Perez-Albuerne EA (1982) Integrated array of photovoltaic cells having minimized shorting losses. US Patent No. 4315096Google Scholar
  12. 12.
    Britt J, Ferekides C (1993) Thin-film CdS/CdTe solar cell with 15.8% efficiency. Appl Phys Lett 62:2851–2852CrossRefGoogle Scholar
  13. 13.
    Wu X, Keane JC, Dhere RG, DeHart C, Duda A, Gessert TA, Sheldon P (2001) 16.5% efficient CdS/CdTe polycrystalline thin-film solar cell. In: Proceedings of the 17th European photovoltaic solar energy conference, Munich, p 995Google Scholar
  14. 14.
    Shay JL, Wagner S, Kasper HM (1975) Efficient CuInSe2/CdS solar cells. Appl Phys Lett 27:89–90CrossRefGoogle Scholar
  15. 15.
    Mickelsen RA, Chen WS, Hsiao YR, Lowe VE (1984) Polycrystalline thin-film CuInSe2/CdZnS solar cells. Electron Devices 5:542–546CrossRefGoogle Scholar
  16. 16.
    Gabor AM, Tuttle JR, Albin DS, Contreras MA, Noufi R, Hermann AM (1994) High-efficiency CuInxGa1−xSe2 solar cells made from (InxGa1−x)2Se3 precursor films. Appl Phys Lett 65:198–200CrossRefGoogle Scholar
  17. 17.
    Chen S, Gong XG, Walsh A, Wei S-H (2009) Crystal and electronic band structure of Cu2ZnSnX4 (X = S and Se) photovoltaic absorbers: first principles insights. Appl Phys Lett 94:041903CrossRefGoogle Scholar
  18. 18.
    Wang K, Gunawan O, Todorov T, Shin B, Chey SJ, Bojarczuk NA, Mitzi D, Guha S (2010) Thermally evaporated Cu2ZnSnS4 solar cells. Appl Phys Lett 97:143508CrossRefGoogle Scholar
  19. 19.
    Repins I, Beall C, Vora N, DeHart C, Kuciauskas D, Dippo P, To B, Mann J, Hsu W-C, Goodrich A, Noufi R (2012) Co-evaporated Cu2ZnSnS4 films and devices. Sol Energy Mater Sol Cells 101:154–159CrossRefGoogle Scholar
  20. 20.
    Todorov TK, Reuter KB, Mitzi DB (2010) High-efficiency solar cell with earth- abundant liquid-processed absorber. Adv Energy Mater 22:E156–E159CrossRefGoogle Scholar
  21. 21.
    Todorov TK, Tang J, Bag S, Gunawan O, Gokmen T, Zhu Y, Mitzi DB (2013) Beyond 11 % efficiency: characteristics of state-of-the-art Cu2ZnSn(S, Se)4 solar cells. Adv Energy Mater 3:34–38CrossRefGoogle Scholar
  22. 22.
    Scragg JJ, Dale PJ, Peter LM (2009) Synthesis and characterization of Cu2ZnSnS4 absorber layers by an electrodeposition-annealing route. Thin Solid Films 517:2481–2484CrossRefGoogle Scholar
  23. 23.
    Chan CP, Lam H, Surya C (2010) Preparation of Cu2ZnSnS4 films by electrodeposition using ionic liquids. Sol Energy Mater Sol Cells 94:207–211CrossRefGoogle Scholar
  24. 24.
    Romero MJ, Dui H, Teeter G, Yan Y, Al-Jassim MM (2011) Comparative study of the luminescence and intrinsic point defects in the kesterite Cu2ZnSnS4 and chalcopyrite Cu(In, Ga)Se2 thin films used in photovoltaic applications. Phys Rev B 84:165324CrossRefGoogle Scholar
  25. 25.
    Thompson BC, Fréchet JMJ (2008) Polymer-fullerene composite solar cells. Ang Chem Int Ed 47:58–77CrossRefGoogle Scholar
  26. 26.
    Sariciftci NS, Smilowitz LB, Heeger AJ, Wudl F (1992) Photoinduced electron transfer from a conducting polymer to buckminsterfullerene. Science 258:1474–1476CrossRefGoogle Scholar
  27. 27.
    Clarke TM, Durrant JR (2010) Charge photogeneration in organic solar cells. Chem Rev 110:6736–6767CrossRefGoogle Scholar
  28. 28.
    Haugeneder A, Neges M, Kallinger C, Spirkl W, Lemmer U, Feldmann J, Scherf U, Harth E, Gügel A, Mllen K (1999) Exciton diffusion and dissociation in conjugated polymer/fullerene blends and heterostructures. Phys Rev B 59:15346–15351CrossRefGoogle Scholar
  29. 29.
    Liang Y, Xu Z, Xia J, Ting Tsai S, Wu Y, Li G, Ray C, Yu L (2010) For the bright future-bulk heterojunction polymer solar cells with power conversion efficiency of 7.4%. Adv Mater 22:E135–E138CrossRefGoogle Scholar
  30. 30.
    He Z, Zhong C, Huang X, Wong WY, Wu H, Chen L, Su S, Cao Y (2011) Simultaneous enhancement of open circuit voltage, short circuit current density and fill factor in polymer solar cells. Adv Mater 23:4636–4643CrossRefGoogle Scholar
  31. 31.
    Ma WL, Yang CY, Gong X, Lee K, Heeger AJ (2005) Thermally stable, efficient polymer solar cells with nanoscale control of the interpenetrating network morphology. Adv Funct Mater 15:1617–1622CrossRefGoogle Scholar
  32. 32.
    Wang T, Pearson AJ, Lidzey DG, Jones RAL (2011) Evolution of structure, optoelectronic properties and device performance of polythiophene: fullerene solar cells during thermal annealing. Adv Funct Mater 21:1383–1390CrossRefGoogle Scholar
  33. 33.
    Pearson AJ, Wang T, Jones RAL, Lidzey DG, Staniec PA, Hopkinson PE, Donald AM (2012) Rationalising phase transitions with thermal annealing temperatures for P3HT: PCBM organic photovoltaic devices. Macromolecules 45:1499–1508CrossRefGoogle Scholar
  34. 34.
    Li G, Shrotriya V, Yao Y, Huang J, Yang Y (2007) Manipulating regioregular poly(3-hexylthiophene): [6, 6]-phenyl-C61-butyric acid methyl ester blends-route towards high efficiency polymer solar cells. J Mater Chem 17:3126–3140CrossRefGoogle Scholar
  35. 35.
    Berson S, De Bettignies R, Bailly S, Guillerez S (2007) Poly(3-hexylthiophene) fibres for photovoltaic applications. Adv Funct Mater 17:1377–1384CrossRefGoogle Scholar
  36. 36.
    Li G, Yao Y, Yang H, Shrotriya V, Yang G, Yang Y (2007) Solvent annealing effect in polymer solar cells based on poly(3-hexylthiophene) and methanofullerenes. Adv Funct Mater 17:1636–1644CrossRefGoogle Scholar
  37. 37.
    Yao Y, Hou J, Xu Z, Li G, Yang Y (2008) Effect of solvent mixtures on the nanoscale phase separation in polymer solar cells. Adv Funct Mater 18:1783–1789CrossRefGoogle Scholar
  38. 38.
    Lee JK, Ma WL, Brabec CJ, Yuen J, Moon JS, Kim JY, Lee K, Bazan GC, Heeger AJ (2008) Processing additives for improved efficiency from bulk heterojunction solar cells. J Am Chem Soc 130:3619–3623CrossRefGoogle Scholar
  39. 39.
    De Sio A, Madena T, Huber R, Parisi J, Neyshtadt S, Deschler F, Da Como E, Esposito S, von Hauff E (2011) Solvent additives for tuning the photovoltaic properties of polymer-fullerene solar cells. Sol Energy Mater Sol Cells 95:3536–3542CrossRefGoogle Scholar
  40. 40.
    Nowell MM, Scarpulla MA, Compaan AD, Liu X, Paudel NR, Kwon D, Wieland KA (2011) Electron backscatter diffraction and photoluminescence of sputtered CdTe thin films. Photovolt Spec Conf 37:001327–001332Google Scholar
  41. 41.
    Nowell MM, Wright SI, Scarpulla MA, Compaan AD, Liu X, Paudel NR, Wieland KA (2012) The correlation of performance in CdTe photovoltaics with grain boundaries. Phys Fail Anal Integ Circ 19:1–7Google Scholar
  42. 42.
    Wald FV, Entine G (1978) Crystal growth of CdTe for γ-ray detectors. Nucl Inst Methods 150:13–23CrossRefGoogle Scholar
  43. 43.
    Toušková DK, Toušek J (1997) Preparation and characterisation of CdS/CdTe thin film solar cells. Thin Solid Films 293:272–276CrossRefGoogle Scholar
  44. 44.
    Hommel D, Waag A, Scholl S, Landwehr G (1992) Chlorine: a new efficient n-type dopant in CdTe layers grown by molecular beam epitaxy. Appl Phys Lett 1:1546–1548CrossRefGoogle Scholar
  45. 45.
    Romeo A, Bätzner DL, Zogg H, Tiwari AN (2000) Recrystallization in CdTe/CdS. Thin Solid Films 361-362:420–425CrossRefGoogle Scholar
  46. 46.
    Niles DW, Waters D, Rose D (1998) Chemical reactivity of CdCl2 wet-deposited on CdTe films studied by X-ray photoelectron spectroscopy. Appl Surf Sci 136:221–229CrossRefGoogle Scholar
  47. 47.
    Terheggen M, Heinrich H, Kostorz G, Baetzner D, Romeo A, Tiwari AN (2004) Analysis of bulk and interface phenomena in CdTe/CdS thin-film solar cells. Interf Sci 12:259–266CrossRefGoogle Scholar
  48. 48.
    Durose K, Edwards PR, Halliday DP (1999) Materials aspects of CdTe/CdS solar cells. J Cryst Growth 197:733–742CrossRefGoogle Scholar
  49. 49.
    Romero MJ, Al-Jassim MM, Dhere RG, Hasoon FS, Contreras MA, Gessert TA, Moutinho HR (2002) Beam injection methods for characterizing thin-film solar cells. Prog Photovolt Res Appl 10:445–455CrossRefGoogle Scholar
  50. 50.
    Consonni V, Feuillet G, Renet S (2006) Spectroscopic analysis of defects in chlorine doped polycrystalline CdTe. J Appl Phys 99:053502CrossRefGoogle Scholar
  51. 51.
    Yan Y, Al-Jassim MM, Jones KM (2003) Structure and effects of double-positioning twin boundaries in CdTe. J Appl Phys 94:2976CrossRefGoogle Scholar
  52. 52.
    Yan Y, Jones KM, Jiang CS, Wu XZ, Noufi R, Al-Jassim MM (2007) Understanding the defect physics in polycrystalline photovoltaic materials. Physica B 401–402:25–32CrossRefGoogle Scholar
  53. 53.
    Yan Y, Jones KM, Al-Jassim MM, Dhere R, Wu X (2011) Transmission electron microscopy study of dislocations and interfaces in CdTe solar cells. Thin Solid Films 519:7168–7172CrossRefGoogle Scholar
  54. 54.
    Ohata K, Saraie J, Tanaka T (1973) Phase diagram of the CdS-CdTe pseudobinary system. Jpn J Appl Phys 12:1198CrossRefGoogle Scholar
  55. 55.
    Lane DW, Conibeer GJ, Wood DA, Capper P, Romani S, Hearne S (1999) Sulfur diffusion in CdTe and the phase diagram of the CdS-CdTe pseudo-binary alloy. J Cryst Growth 197:743–748CrossRefGoogle Scholar
  56. 56.
    Lane DW, Rogers KD, Painter JD, Wood DA, Ozsan ME (2000) Structural dynamics in CdS-CdTe thin films. Thin Solid Films 361–362:1–8CrossRefGoogle Scholar
  57. 57.
    Moutinho HR, Dhere RG, Jiang C-S, Yan Y, Albin DS, Al-Jassim MM (2010) Investigation of potential and electric field profiles in cross sections of CdTe/CdS solar cells using scanning Kelvin probe microscopy. J Appl Phys 108:074503CrossRefGoogle Scholar
  58. 58.
    Albin DS, Yan Y, Al-Jassim MM (2002) The effect of oxygen on interface microstructure evolution in CdS/CdTe solar cells. Prog Photovolt Res Appl 10:309–322CrossRefGoogle Scholar
  59. 59.
    Edwards PR, Halliday DP, Durose K, Richter H, Bonnet D (1997) The influence of CdCl2 treatment and interdiffusion on grain boundary passivation in CdTe/CdS solar cells. In: Proceedings of the 14th European photovoltaic solar energy conference, Barcelona, pp 2083–2086Google Scholar
  60. 60.
    McCandless BE, Engelmann MG, Birkmire RW (2001) Interdiffusion of the CdS/CdTe thin films: modeling x-ray diffraction line profiles. J Appl Phys 89:988–994CrossRefGoogle Scholar
  61. 61.
    Metzger WK, Albin D, Romero MJ, Dippo P, Young M (2006) CdCl2 treatment, S diffusion and recombination in polycrystalline CdTe. J Appl Phys 99:103703CrossRefGoogle Scholar
  62. 62.
    Gessert TA, Burst JM, Wei S-H, Ma J, Kuciauskas D, Rance WL, Barnes TM, Duenow JN, Reese MO, Li JV, Yound MR, Dippo P (2012) Pathways toward higher performance CdS/CdTe devices: Te exposure of CdTe surface before ZnTe:Cu/Ti contacting. Thin Solid Films 535:237–240Google Scholar
  63. 63.
    Jarkov A, Bereznev S, Laes K, Volobujeva O, Traksmaa R, ÖPik A, Mellikov E (2011) Conductive polymer PEDOT: PSS back contact for CdTe solar cell. Thin Solid Films 519:7449–7452CrossRefGoogle Scholar
  64. 64.
    Taylor AA, Major JD, Phillips L, McLeod I, Durose K, Mendis B.G Manuscript in preparationGoogle Scholar
  65. 65.
    Irvine SJC, Barrioz V, Lamb D, Jones EW, Rowlands-Jones RL (2008) MOCVD of thin film photovoltaic solar cells – next generation production technology? J Cryst Growth 310:5198–5203CrossRefGoogle Scholar
  66. 66.
    Swanson DE, Lutze RM, Sampath WS, Williams JD (2012) Plasma cleaning of TCO surfaces prior to CdS/CdTe deposition. Photovolt Spec Conf 38:000859–000863Google Scholar
  67. 67.
    Gabor AM, Tuttle JR, Bode MH, Franz A, Tennant AL, Contreras MA, Noufi R, Jensen DG, Hermann AM (1996) Band-gap engineering in Cu(In, Ga)Se2 thin films grown from (In, Ga)2Se3 precursors. Sol Energy Mater Sol Cells 41:247–260CrossRefGoogle Scholar
  68. 68.
    Dullweber T, Lundberg O, Malmström J, Bodegård M, Stolt L, Rau U, Schock H-W, Werner JH (2001) Back surface band gap gradings in Cu(In,Ga)Se2 solar cells. Thin Solid Films 387:11–13CrossRefGoogle Scholar
  69. 69.
    Wada T, Kohara N, Nishiwaki S, Negami T (2001) Characterization of the Cu(In, Ga)Se2/Mo interface in CIGS solar cells. Thin Solid Films 387:118–122CrossRefGoogle Scholar
  70. 70.
    Nishiwaki S, Kohara N, Negami T, Wada T (1998) MoSe2 layer formation at Cu(In, Ga)Se2/Mo interfaces in high efficiency Cu(In1−xGax)Se2 solar cells. Jpn J Appl Phys 37:L71–L73CrossRefGoogle Scholar
  71. 71.
    Scheer R, Diesner K, Lewerenz H-J (1995) Experiments on the microstructure of evaporated CuInS2 thin films. Thin Solid Films 268:130–136CrossRefGoogle Scholar
  72. 72.
    Klenk R, Walter T, Schmid D, Schock HW (1993) Growth mechanisms and diffusion in multinary and multilayer chalcopyrite thin films. Jpn J Appl Phys 32:57–61CrossRefGoogle Scholar
  73. 73.
    Hasoon FS, Yan Y, Althani H, Jones KM, Moutinho HR, Alleman J, Al- Jassim MM, Noufi R (2001) Microstructural properties of Cu(In,Ga)Se2 thin films used in high-efficiency devices. Thin Solid Films 387:1–5CrossRefGoogle Scholar
  74. 74.
    Wei S-H, Zunger A (1995) Band offsets and optical bowings of chalcopyrites and Zn- based II-VI alloys. J Appl Phys 78:3846–3856CrossRefGoogle Scholar
  75. 75.
    Abou-Ras D, Schorr S, Schock H-W (2007) Grain-size distributions and grain boundaries of chalcopyrite-type thin films. J Appl Crystallogr 40:841–848CrossRefGoogle Scholar
  76. 76.
    Abou-Ras D, Koch CT, Vüstner V, van Aken PA, Jahn U, Contreras MA, Ca-ballero R, Kaufmann CA, Scheer R, Unold T, Schock H-W (2009) Grain-boundary types in chalcopyrite-type thin films and their correlations with film texture and electrical properties. Thin Solid Films 517:2545–2549CrossRefGoogle Scholar
  77. 77.
    Ott N, Hanna G, Rau U, Werner JH, Strunk HP (2004) Texture of Cu(In, Ga)Se2 thin films and nanoscale cathodoluminescence. J Phys Condens Matter 16:S85CrossRefGoogle Scholar
  78. 78.
    Repins I, Contreras M, Romero M, Yan Y, Metzger W, Li J, Johnston S, Egaas B, DeHart C, Scharf J, McCandless BE, Noufi R (2008) Characterization of 19.9% efficient CIGC absorbers. Photovolt Spec Conf 33:1–6Google Scholar
  79. 79.
    Romero MJ, Ramanathan K, Contreras MA, Al-Jassim MM, Noufi R, Sheldon P (2003) Cathodoluminescence of Cu(In, Ga)Se2 thin films used in high-efficiency solar cells. Appl Phys Lett 83:4770–4772CrossRefGoogle Scholar
  80. 80.
    Shklovskii BI, Efros AL (1984) Electronic properties of doped semiconductors. Springer, Germany.CrossRefGoogle Scholar
  81. 81.
    Bodegård M, Stolt L, Hedstrom J (1994) The influence of sodium on the grain structure of CuInSe2 films for photovoltaics applications. Eur Sol Energy Conf 12:1743–1746Google Scholar
  82. 82.
    Bodegård M, Granath K, Stolt L (2000) Growth of Cu(In,Ga)Se2 thin films by coevaporation using alkaline precursors. Thin Solid Films 361:9–16CrossRefGoogle Scholar
  83. 83.
    Rudmann D, Bilger G, Kaelin M, Haug F-J, Zogg H, Tiwari AN (2003) Effects of NaF coevaporation on the structural properties of Cu(In, Ga)Se2 thin films. Thin Solid Films 431:37–40CrossRefGoogle Scholar
  84. 84.
    Jasenek A, Rau U, Nadenau V, Schock H-W (2000) Electronic properties of CuGaSe- based heterojunction solar cells. Part II. Defect Spectroscopy. J Appl Phys 87:594CrossRefGoogle Scholar
  85. 85.
    Rudmann D, Da Cunha AF, Kaelin M, Kurdesau F, Zogg H, Tiwari AN, Bilger G (2004) Efficiency enhancement of Cu(In, Ga)Se2 solar cells due to post-deposition Na incorporation. Appl Phys Lett 84:1129–1131CrossRefGoogle Scholar
  86. 86.
    Cahen D, Noufi R (1989) Defect chemical explanation for the effect of air anneal on CdS/CuInSe2 solar cell performance. Appl Phys Lett 54:558–560CrossRefGoogle Scholar
  87. 87.
    Lei C, Li CM, Rockett A, Robertson IM (2007) Grain boundary compositions in Cu(In, Ga)Se2. J Appl Phys 101:024909CrossRefGoogle Scholar
  88. 88.
    Abou-Ras D, Schaffer B, Schaffer M, Schmidt SS, Caballero R, Unold T (2012) Direct insight into grain boundary reconstruction in polycrystalline Cu(In, G)Se2with atomic resolution. Phys Rev Lett 108:075502CrossRefGoogle Scholar
  89. 89.
    Niles DW, Al-Jassim MM, Ramanathan K (1999) Direct observation of Na and O impurities at grain surfaces of CuInSe2 thin films. J Vacuum Sci Technol A Vacuum, Surf Films 17:291–296CrossRefGoogle Scholar
  90. 90.
    Cadel E, Barreau N, Kessler J, Pareige P (2010) Atom probe study of sodium distribution in polycrystalline Cu(In, Ga)Se2 thin film. Acta Mater 58:2634–2637CrossRefGoogle Scholar
  91. 91.
    Scheer R, Schock H-W (2011) Chalcogenide photovoltaics: physics, technologies and thin film devices. Wiley-VCH Verlag GmbH & Co. KGaA, GermanyCrossRefGoogle Scholar
  92. 92.
    Nagoya A, Asahi R, Wahl R, Kresse G (2010) Defect formation and phase stability of Cu2ZnSnS4 photovoltaic materials. Phys Rev B 81:113202CrossRefGoogle Scholar
  93. 93.
    Mendis BG, Shannon MD, Goodman MCJ, Major JD, Claridge R, Halliday DP, Durose K (2012) Direct observation of Cu, Zn cation disorder in Cu2ZnSnS4 solar cell absorber material using aberration corrected scanning electron microscopy. Prog Photovolt Res Appl. doi:10.1002/pip.2279Google Scholar
  94. 94.
    Schorr S (2011) The crystal structure of kesterite type compounds: a neutron and X-ray diffraction study. Sol Energy Mater Sol Cells 95:1482–1488CrossRefGoogle Scholar
  95. 95.
    Wätjen TW, Engman J, Edoff M, Platzer-Björkman C (2012) Direct evidence of current blocking by ZnSe in Cu2ZnSnSe4 solar cells. Appl Phys Lett 100:173510CrossRefGoogle Scholar
  96. 96.
    Dale PJ, Hoenes K, Scragg JJ, Siebentritt S (2009) A review of the challenges facing kesterite based thin film solar cells. Photovolt Specialists Conf (PVSC) 34:002080–002085Google Scholar
  97. 97.
    Fontané X, Calvo-Barrio L, Izquierdo-Roca Z, Saucedo E, Pérez-Rodriguez A, Morante JR, Berg DM, Dale PJ, Siebentritt S (2011) In-depth resolved Raman scattering analysis for the identification of secondary phases: characterisation of Cu2ZnSnS4 layers for solar cell applications. Appl Phys Lett 98:181905CrossRefGoogle Scholar
  98. 98.
    Wang K, Shin B, Reuter KB, Todorov T, Mitzi DB, Guha S (2011) Structural and elemental characterization of high efficiency Cu2ZnSnS4 solar cells. Appl Phys Lett 98:051912CrossRefGoogle Scholar
  99. 99.
    Platzer-Björkman C, Scragg JJ, Flammersberger H, Kubart T, Edoff M (2012) Influence of precursor sulfur content on the film formation and compositional changes in Cu2ZnSnS4 films and solar cells. Sol Energy Mater Sol Cells 98:110–117CrossRefGoogle Scholar
  100. 100.
    Scragg JJ, Dale PJ, Colombara D, Peter LM (2012) Thermodynamic aspects of the synthesis of then-film materials for solar cells. Chem Phys Chem 13:3035–3046Google Scholar
  101. 101.
    Wätjen TW, Scragg JJ, Ericson T, Edoff M, Platzer-Björkman C (2012) Secondary compound formation revealed by transmission electron microscopy at the Cu2ZnSnS4/Mo interface. Thin Solid Films 535:31–34CrossRefGoogle Scholar
  102. 102.
    Barkhouse DAR, Gunawan O, Gokmen T, Todorov TK, Mitzi DB (2012) Device characteristics of a 10.1 % hydrazine-processed Cu2ZnSn(Se, S)4 solar cell. Prog Photovolt Res Appl 20:6–11CrossRefGoogle Scholar
  103. 103.
    Taretto K, Rau U, Werner JH (2005) Numerical simulation of grain boundary effects in Cu(In,Ga)Se2 thin film solar cells. Thin Solid Films 480–481:8–12CrossRefGoogle Scholar
  104. 104.
    Nerat M, Černivec G, Smole F, Topič M (2008) Simulation study of the effects of grain shape and size on the performance of Cu(In,Ga)Se2 solar cells. J Appl Phys 104:083706CrossRefGoogle Scholar
  105. 105.
    Metzger WK, Gloeckler M (2005) The impact of charged grain boundaries on thin film solar cells and characterisation. J Appl Phys 98:063701CrossRefGoogle Scholar
  106. 106.
    Gloeckler M, Sites JR, Metzger WK (2005) Grain boundary recombination in Cu(In, Ga)Se2 solar cells. J Appl Phys 98:113704CrossRefGoogle Scholar
  107. 107.
    Major JD, Proskuryakov YY, Durose K, Zoppi G, Forbes I (2010) Control of grain size in sublimation grown CdTe and the improvement in performance of devices with systematically increased grain size. Sol Energy Mater Sol Cells 94:1107–1112CrossRefGoogle Scholar
  108. 108.
    Visoly-Fisher I, Cohen SR, Gartsman K, Ruzin A, Cahen D (2006) Understanding the beneficial role of grain boundaries in polycrystalline solar cells from single grain boundary scanning probe microscopy. Adv Funct Mater 16:649–660CrossRefGoogle Scholar
  109. 109.
    Jiang CS, Noufi R, Ramanathan K, AbuShama JA, Moutinho HR, Al-Jassim MM (2004) Does the local built-in potential on grain boundaries of Cu(In, Ga)Se2 thin films benefit photovoltaic performance of the device? Appl Phys Lett 85:2625–2627CrossRefGoogle Scholar
  110. 110.
    Terheggen M, Heinrich H, Kostorz G, Romeo A, Baetzner D, Tiwari AN, Bosio A, Romeo N (2003) Structural and chemical interface characterisation of CdTe solar cells by transmission electron microscopy. Thin Solid Films 431–432:262–266CrossRefGoogle Scholar
  111. 111.
    Yan Y, Al-Jassim MM, Jones KM (2004) Passivation of double positioning twin boundaries in CdTe. J Appl Phys 96:320–326CrossRefGoogle Scholar
  112. 112.
    Zhang L, Da Silva JLF, Li J, Yan Y, Gessert TA, Huai Wei S (2008) Effect of co-passivation of Cl and Cu on CdTe grain boundaries. Phys Rev Lett 101:155501CrossRefGoogle Scholar
  113. 113.
    Hofmann DM, Omling P, Grimmeiss HG, Meyer BK, Benz KW, Sinerius D (1992) Identification of the chlorine A-centre in CdTe. Phys Rev B 45:6247–6250CrossRefGoogle Scholar
  114. 114.
    Halliday DP, Eggleston JM, Durose K (1998) A photoluminescence study of polycrystalline thin film CdTe/CdS solar cells. J Cryst Growth 186:543–549CrossRefGoogle Scholar
  115. 115.
    Galloway SA, Edwards PR, Durose K (1999) Characterisation of thin film CdS/CdTe solar cells using electron and optical beam induced current. Sol Energy Mater Sol Cells 57:61–74CrossRefGoogle Scholar
  116. 116.
    Edwards PR, Galloway SA, Durose K (2000) Erratum to EBIC and luminescence mapping of CdTe/CdS solar cells. Thin Solid Films 372:284–291CrossRefGoogle Scholar
  117. 117.
    Visoly-Fisher I, Cohen SR, Cahen D (2003) Direct evidence for grain boundary depletion in polycrystalline CdTe from nanoscale resolved measurements. Appl Phys Lett 82:556–558CrossRefGoogle Scholar
  118. 118.
    Woods LM, Levi DH, Kaydanov V, Robinson GY, Ahrenkiel RK (1998) Proceedings of 2nd world conference on photovoltaic solar energy conversion, vol 1. European Commission, Ispra, Italy, p 1043–1046Google Scholar
  119. 119.
    Woods LM, Robinson GY, Levi DH (2000) The effects of CdCl2 on CdTe electrical properties using a new theory for grain boundary conduction. Proceedings of 28th IEEE photovoltaic specialists conference. IEEE, Piscataway, NJ, p 603–606Google Scholar
  120. 120.
    Cojocaru-Mirédin O, Choi P, Wuerz R, Raabe D (2011) Atomic scale distribution of impurities in CuInSe2-based thin film solar cells. Ultramicroscopy 111:552–556CrossRefGoogle Scholar
  121. 121.
    Jiang CS, Noufi R, AbuShama JA, Ramanathan K, Moutinho HR, Pankow J, Al-Jassim MM (2004) Local built-in potential on grain boundary of Cu(In, Ga)Se2. Appl Phys Lett 84:3477CrossRefGoogle Scholar
  122. 122.
    Azulay D, Balberg I, Millo O (2012) Microscopic evidence for the modification of the electronic structure at grain boundaries of Cu(In1−xGax)Se2 films. Phys Rev Lett 108:076603CrossRefGoogle Scholar
  123. 123.
    Yan Y, Jiang CS, Noufi R, Huai Wei S, Moutinho HR, Al-Jassim MM (2007) Electrically benign behaviour of grain boundaries in polycrystalline CuInSe2 films. Phys Rev Lett 99:235504CrossRefGoogle Scholar
  124. 124.
    Mönig H, Smith Y, Caballero R, Kaufmann CA, Lauermann I, Lux-Steiner MCH, Sadewasser S (2010) Direct evidence for a reduced density of deep level defects at grain boundaries of Cu(In,Ga)Se2 thin films. Phys Rev Lett 105:116802CrossRefGoogle Scholar
  125. 125.
    Persson C, Zunger A (2003) Anomalous grain boundary physics in polycrystalline CuInSe2: the existence of a hole barrier. Phys Rev Lett 91:266401CrossRefGoogle Scholar
  126. 126.
    Zhang SB, Huai Wei S, Zunger A, Katayama-Yoshida H (1998) Defect physics of the CuInSe2 chalcopyrite semiconductor. Phys Rev B 57:9642–9655CrossRefGoogle Scholar
  127. 127.
    Donolato C (1983) Theory of beam induced current characterisation of grain boundaries in polycrystalline solar cells. J Appl Phys 54:1314–1322CrossRefGoogle Scholar
  128. 128.
    Mendis BG, Bowen L, Jiang QZ (2010) A contactless method for measuring the re-combination velocity of an individual grain boundary in thin film photovoltaics. Appl Phys Lett 97:092112CrossRefGoogle Scholar
  129. 129.
    Corkish R, Puzzer T, Sproul AB, Luke KL (1998) Quantitative interpretation of electron beam induced current grain boundary contrast profiles with application to silicon. J Appl Phys 84:5473–5481CrossRefGoogle Scholar
  130. 130.
    Van Roosbroeck W (1955) Injected current carrier transport in a semi-infinite semiconductor and the determination of lifetimes and surface recombination velocities. J Appl Phys 26:380–391CrossRefGoogle Scholar
  131. 131.
    Watson CCR, Durose K (1993) Cathodoluminescence microscopy of bulk CdTe crystals. J Cryst Growth 126:325–329CrossRefGoogle Scholar
  132. 132.
    Mendis BG, Goodman MCJ, Major JD, Taylor AA, Durose K, Halliday DP (2012) The role of secondary phase precipitation on grain boundary electrical activity in Cu2ZnSnS4 (CZTS) photovoltaic absorber layer material. J Appl Phys 112:124508CrossRefGoogle Scholar
  133. 133.
    Mendis BG, Bowen L (2011) Cathodoluminescence measurement of grain boundary recombination velocity in vapour grown p-CdTe. J Phys Conf Ser 326:012017CrossRefGoogle Scholar
  134. 134.
    Allen LJ, McBride W, O’Leary NL, Oxley MP (2004) Exit wave reconstruction at atomic resolution. Ultramicroscopy 100:91–104CrossRefGoogle Scholar
  135. 135.
    Bhattacharyya S, Koch CT, Rühle M (2006) Projected potential profiles across inter- faces obtained by reconstructing the exit face wavefunction from through focal series. Ultramicroscopy 106:525–538CrossRefGoogle Scholar
  136. 136.
    Abou-Ras D, Schmidt SS, Caballero R, Unold T, Werner Schock H, Koch CT, Schaffer B, Schaffer M, Pa Choi P, Cojocaru-Mirédin O (2012) Confined and chemically flexible grain boundaries in polycrystalline compound semiconductors. Adv Energy Mater 2:992–998CrossRefGoogle Scholar
  137. 137.
    Dunin-Borkowski RE (2000) The development of Fresnel contrast analysis and the interpretation of mean inner potential profiles at interfaces. Ultramicroscopy 83:193–216CrossRefGoogle Scholar
  138. 138.
    Dunin-Borkowski RE, Saxton WO (1997) The electrostatic contribution to the forward scattering potential at a space charge layer in high energy electron diffraction. II fringing fields. Acta Crystallogr A 53:242–250CrossRefGoogle Scholar
  139. 139.
    Oualid J, Singal CM, Dugas J, Crest JP, Amzil H (1984) Influence of illumination on the grain boundary recombination velocity in silicon. J Appl Phys 55:1195–1205CrossRefGoogle Scholar
  140. 140.
    Midgley PA, Weyland M (2003) 3D electron microscopy in the physical sciences: the development of Z-contrast and EFTEM tomography. Ultramicroscopy 96:413–431CrossRefGoogle Scholar
  141. 141.
    van Bavel SS, Loos J (2010) Volume organisation of polymer and hybrid solar cells as revealed by electron tomography. Adv Funct Mater 20:3217–3234CrossRefGoogle Scholar
  142. 142.
    Huynh WU, Dittmer JJ, Alivisatos AP (2002) Hybrid nanorod-polymer solar cells. Science 295:2425–2427CrossRefGoogle Scholar
  143. 143.
    Oosterhout SD, Wienk MM, van Bavel SS, Thiedmann R, Koster LJA, Gilot J, Loos J, Schmidt V, Janssen RAJ (2009) The effect of three-dimensional morphology on the efficiency of hybrid polymer solar cells. Nat Mater 8:818–824CrossRefGoogle Scholar
  144. 144.
    Hindson JC, Saghi Z, Hernandez-Garrido JC, Midgley PA, Greenham NC (2011) Morphological study of nanoparticle-polymer solar cells using high angle annular dark field electron tomography. Nano Lett 11:904–909CrossRefGoogle Scholar
  145. 145.
    van Bavel SS, Sourty E, de With G, Loos J (2009) Three dimensional nanoscale organisation of bulk heterojunction polymer solar cells. Nano Lett 9:507–513CrossRefGoogle Scholar
  146. 146.
    Brinkmann M, Wittmann JC (2006) Orientation of regioregular poly(3-hexylthiophene) by directional solidification: a simple method to reveal the semicrystalline structure of a conjugated polymer. Adv Mater 18:860–863CrossRefGoogle Scholar
  147. 147.
    Yang X, Loos J (2007) Toward high-performance polymer solar cells: the importance of morphology control. Macromolecules 40:1353–1362CrossRefGoogle Scholar
  148. 148.
    Herzing AA, Richter LJ, Anderson IM (2010) 3D nanoscale characterisation of thin film organic photovoltaic device structures via spectroscopic contrast in the TEM. J Phys Chem C 114:17501–17508CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  1. 1.Physics DepartmentDurham UniversityDurhamUK

Personalised recommendations