Hidden parameters in the plasma deposition of microcrystalline silicon solar cells
- PDF / 353,138 Bytes
- 8 Pages / 585 x 783 pts Page_size
- 98 Downloads / 170 Views
Hidden parameters in the plasma deposition of microcrystalline silicon solar cells M.N. van den Donker,a) B. Rech,b) R. Schmitz, J. Klomfass, G. Dingemans, and F. Fingerc) Institut fu¨r Energieforachung-Photovaltank (IPV), Forschungszentrum Jülich GmbH, Jülich 52425, Germany
L. Houben Institut fu¨r Festkorpenforschung (IFF), Forschungszentrum Jülich GmbH, Jülich 52425, Germany
W.M.M. Kessels and M.C.M. van de Sanden Applied Physics, Technical University (TU) Eindhoven, Eindhoven 5600MB, The Netherlands (Received 2 January 2007; accepted 21 March 2007)
The effect of process parameters on the plasma deposition of c-Si:H solar cells is reviewed in this article. Several in situ diagnostics are presented, which can be used to study the process stability as an additional parameter in the deposition process. The diagnostics were used to investigate the stability of the substrate temperature during deposition at elevated power and the gas composition during deposition at decreased hydrogen dilution. Based on these investigations, an updated view on the role of the process parameters of plasma power, heater temperature, total gas flow rate, and hydrogen dilution is presented.
I. INTRODUCTION
Microcrystalline silicon (c-Si:H) provides a promising route toward solar cells with high stabilized efficiency and cost-effective large-area production.1,2 Figure 1 shows a transmission electron microscope (TEM) image of a single-junction c-Si:H solar cell, consisting of glass, textured ZnO, c-Si:H p-i-n junction, and back contact. Deposition of the intrinsic c-Si:H film takes place in vapor-phase vacuum processes involving a silicon-containing source gas. The deposition process has received considerable scientific interest since the deposited material quality and the deposition rate at which it is obtained are crucial to the performance and price of eventually produced commercial solar modules.
a)
Present address: Solland Solar Cells BV, Bohr 10, 6422 RL, Heerlen, The Netherlands b) Present address: Department Silicon Photovoltaics (SE1), HahnMeitner-Institut Berlin, Kekuléstraße 5, 12489 Berlin, Germany c) Address all correspondence to this author. e-mail: [email protected] This paper was selected as the Outstanding Meeting Paper for the 2006 MRS Spring Meeting Symposium A Proceedings, Vol. 910. DOI: 10.1557/JMR.2007.0226 J. Mater. Res., Vol. 22, No. 7, Jul 2007
http://journals.cambridge.org
Downloaded: 09 Apr 2015
A commonly used source gas is SiH4. Reactive radicals are formed from this gas by (for example) thermal dissociation using a hot wire or electron-impact dissociation using plasma. Known plasma sources are, for example, an expanding thermal plasma,3 inductivelycoupled plasma,4 or microwave plasma.5 In this work, we restricted ourselves to the parallel plate plasma source. This specific plasma source is used commonly in research and industry. Thus far, it has shown to be the best solar cell performance at high rate. It consists of two parallel electrodes, of which one is grounded (the substrate) and the o
Data Loading...
