Université de Neuchâtel

Intrinsic microcrystalline silicon (μc-Si:H)-a promising newthin film solar cell material

Meier, Johannes ; Dubail, S. ; Flückiger, R. ; Fischer, Diego ; Keppner, Herbert ; Shah, Arvind

In: Conference Record of the Twenty Fourth IEEE Photovoltaic Specialists Conference (1994 IEEE First World Conference on Photovoltaic Energy Conversion), 1994, vol. 1, p. 409-412

“Compensated” microcrystalline silicon is obtained by adding 8-20 ppm diborane in the plasma gas phase. p-i-n cells with such i-layers have increased infrared sensitivity when compared to a-Si:H p-i-n cells. The preparation of the world's first “mixed stacked” a-Si:H/μc-Si:H tandem cell with an initial efficiency of 9.1% is reported. The μc-Si:H cells showed no degradation of the cell...

Université de Neuchâtel

a-Si:H/a-Si:H stacked cell from VHF-deposition in a single chamber reactor with 9% stabilized efficiency

Platz, R. ; Fischer, Diego ; Dubail, S. ; Shah, Arvind

In: Solar Energy Materials and Solar Cells, 1997, vol. 46, no. 2, p. 157-172

In the present paper we present results on a-Si:H/a-Si:H stacked cells deposited in a single-chamber reactor by the very high frequency-glow discharge (VHF-GD) deposition technique at 70 MHz. Hydrogen dilution of the i-layer yields more stable amorphous p−i−n solar cells, similar to what is observed for RF deposition. High dilution ratios of the i-layer are found to enhance contaminations....

Université de Neuchâtel

Recent progress in micromorph solar cells

Meier, Johannes ; Dubail, S. ; Cuperus, J. ; Kroll, U. ; Platz, R. ; Torres, Pedro ; Anna Selvan, J. A. ; Pernet, P. ; Beck, N. ; Pellaton Vaucher, N. ; Hof, Ch. ; Fischer, Diego ; Keppner, Herbert ; Shah, Arvind

In: Journal of Non-Crystalline Solids, 1998, vol. 227-230, p. 1250-1256

Recently, we have demonstrated that intrinsic hydrogenated microcrystalline silicon, as deposited by the very high frequency glow-discharge technique, can be used as the active layers of p–i–n solar cells. Our microcrystalline silicon represents a new form of thin film crystalline silicon that can be deposited (in contrast to any other approach found in literature) at substrate temperatures...

Université de Neuchâtel

Towards high-efficiency thin-film silicon solar cells with the “micromorph” concept

Meier, Johannes ; Dubail, S. ; Platz, R. ; Torres, Pedro ; Kroll, U. ; Anna Selvan, J. A. ; Pellaton Vaucher, N. ; Hof, Ch. ; Fischer, D. ; Keppner, Herbert ; Flückiger, R. ; Shah, Arvind ; Shklover, V. ; Ufert, K. -D.

In: Solar Energy Materials and Solar Cells, 1997, vol. 49, no. 1-4, p. 35-44

Tandem solar cells with a microcrystalline silicon bottom cell (1 eV gap) and an amorphous-silicon top cell (1.7 eV gap) have recently been introduced by the authors; they were designated as “micromorph” tandem cells. As of now, stabilised efficiencies of 11.2% have been achieved for micromorph tandem cells, whereas a 10.7% cell is confirmed by ISE Freiburg. Micromorph cells show a rather low...

Université de Neuchâtel

Controlled nucleation of thin microcrystalline layers for the recombination junction in a-Si stacked cells

Pellaton Vaucher, N. ; Rech, B. ; Fischer, D. ; Dubail, S. ; Goetz, M. ; Keppner, Herbert ; Wyrsch, Nicolas ; Beneking, C. ; Hadjadj, O. ; Shklover, V. ; Shah, Arvind

In: Solar Energy Materials and Solar Cells, 1997, vol. 49, no. 1-4, p. 27-33

In high-efficiency a-Si : H based stacked cells, at least one of the two layers that form the internal n/p junction has preferentially to be microcrystalline so as to obtain sufficient recombination at the junction [1–6]. The crucial point is the nucleation of a very thin μc-Si : H layer on an amorphous (i-layer) substrate [2, 4]. In this study, fast nucleation is induced through the treatment...

Université de Neuchâtel

Microcrystalline/micromorph silicon thin-film solar cells prepared by VHF-GD technique

Meier, Johannes ; Vallat-Sauvain, Evelyne ; Dubail, S. ; Kroll, U. ; Dubail, J. ; Golay, S. ; Feitknecht, Luc ; Torres, Pedro ; Faÿ, Sylvie ; Fischer, D. ; Shah, Arvind

In: Solar Energy Materials and Solar Cells, 2001, vol. 66, no. 1-4, p. 73-84

Hydrogenated microcrystalline silicon prepared at low temperatures by the glow discharge technique is examined here with respect to its role as a new thin-film photovoltaic absorber material. XRD and TEM characterisations reveal that microcrystalline silicon is a semiconductor with a very complex morphology. Microcrystalline p–i–n cells with open-circuit voltages of up to 560–580 mV could...

Université de Neuchâtel

Microcrystalline silicon and the impact on micromorph tandem solar cells

Meier, Johannes ; Dubail, S. ; Golay, S. ; Kroll, U. ; Faÿ, Sylvie ; Vallat-Sauvain, Evelyne ; Feitknecht, Luc ; Dubail, J. ; Shah, Arvind

In: Solar Energy Materials and Solar Cells, 2002, vol. 74, no. 1-4, p. 457-467

Intrinsic microcrystalline silicon opens up new ways for silicon thin-film multi-junction solar cells, the most promising being the “micromorph” tandem concept. The microstructure of entirely microcrystalline p–i–n solar cells is investigated by transmission electron microscopy. By applying low pressure chemical vapor deposition ZnO as front TCO in p–i–n configurated micromorph...

Université de Neuchâtel

The “Micromorph” cell: a new way to high-efficiency-low-temperature crystalline silicon thin-film cell manufacturing?

Keppner, H. ; Kroll, U. ; Torres, P. ; Meier, J. ; Platz, R. ; Fischer, D. ; Beck, N. ; Dubail, S. ; Anna Selvan, J. A. ; Pellaton Vaucher, N. ; Goerlitzer, M. ; Ziegler, Y. ; Tscharner, R. ; Hof, Ch. ; Goetz, M. ; Pernet, P. ; Wyrsch, Nicolas ; Vuille, J. ; Cuperus, J. ; Shah, Arvind ; Pohl, J.

In: AIP Conference Proceeding, 1997, vol. 394, no. 1, p. 271-281

Hydrogenated microcrystalline Silicon (µc-Si:H) produced by the VHF-GD (Very High Frequency Glow Discharge) process can be considered to be a new base material for thin-film crystalline silicon solar cells. The most striking feature of such cells, in contrast to conventional amorphous silicon technology, is their stability under light-soaking. With respect to crystalline silicon technology,...