CIGS solar cells

Thin-film solar cell devices based on CIGS have already demonstrated an efficiency of 19.52%.40 The direct energy gap of CIGS results in a large optical absorption coefficient, which, in turn, permits the use of thin (-1 pm) layers of active material. CIGS solar cells are also known for their long-term stability.76... 

Mikami, R. Miyazaki, H. Abe, T. Yamada, A. Konagai, M. 2003. Chemical bath deposited (CBD)-ZnO buffer layer for CIGS solar cells. Edited by Kurokawa, K. Kazmerski, L. L. McNelis, B. Yamaguchi, M. Wronski, C. Sinke, W. C. Proceedings of 3rd World Conference on Photovoltaic Energy Conversion (IEEE Cat. No. 03CH37497). PI Vol. 1. pp. 519-522. 

A thin i-ZnO (intrinsic ZnO) layer is often used as a buffer layer in CIS/CIGS solar cells, between the absorber part of the cell and the front TCO. The role of this resistive (buffer) layer is mainly to provoke suitable field-assisted hole collection at the contact interface, reducing, thus, the recombination rate at and near the ZnO/CIS or ZnO/CIGS interface (see also Chap. 9). 

Front ZnO layers Somewhat similarly to the case of ZnO films that are used as window layers in CIS/CIGS solar cells, the front ZnO in a thin film silicon solar cell has to fulfill the following criteria ... 

To conclude we may say that, for thin film silicon solar cells (just as in the case of CIS/CIGS solar cells), the low-temperature LP-CVD process is preferred over the AP-CVD process, in all cases for where ZnO is deposited as the last layer this is the bottom layer ZnO for the p-i-n configuration and the top layer ZnO for the n-i-p configuration. 

To improve the junction property between CIGS absorber/Zn(0,S,OH)j and ZnO B window, Sang et al. [55] inserted an undoped thin CVD ZnO layer between the Zn(0,S,0H)a buffer and the ZnO B window. They observed an increase of both the Voc and FF, leading to a 30 x 30 cm2 submodule (aperture area = 864 cm2) with 12.93% efficiency. Finally, Olsen et al. [67] reached an efficiency of 13.95% (aperture area 0.13 cm2) for CIGS solar cells using a CVD ZnO buffer layer (see also Chaps. 4 and 9). 

Figure 16 Schematic representation of a typical CIGS solar cell...

Demonstrated 12% efficiency in in-house fabricated CIGS solar cells (2" x 4"). 

Figure 1.2 Comparison of superstrate and substrate solar cell configurations, (a) Superstrate configuration used for CdSjCdTe solar cells, (b) Substrate configuration commonly used for CIGS solar cells.

Herz, K., Eicke, A., Kessler, F, Wachter, R., Powalla, M. (2003) Diffusion barriers for CIGS solar cells on metallic substrates. Thin Solid Films, 431-432,392-397. 

Saji, VS, Choi, I.K., Lee, C.W. Progress in electrodeposited absorber layer for Culn j Ga Se (CIGS) solar cells . Solar Energy, 2011b, 85,2666-78. 

Figure 3.8 CIGS solar cell configurations (a) superstrate configuration (b) substrate configuration. Adapted from Romeo et al., 2004 with permission from John Wiley Sons, Ltd...

A mesoporous ClOl dye-sensitised TiOi film was directly sandwiched with a platinised CIGS solar cell using a spacer, avoiding the back glass electrode commonly used in the The void was filled through a... 

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