Papers by Guido Agostinelli
The measurement of quantum efficiency with bias voltage is a powerful tool to characterize CdTe/C... more The measurement of quantum efficiency with bias voltage is a powerful tool to characterize CdTe/CdS solar cell. As the quantum efficiency changes drastically with bias it will be referred to as Apparent Quantum Efficiency AQE. The AQE gives insight to the spectral contents of the cell current and therefore resolves the spatial carrier collection in the cell at each working
Modelling the fill factor and maximum power point of a solar cell normally results in expressions... more Modelling the fill factor and maximum power point of a solar cell normally results in expressions which require a numerical solution. The development of an energy rating model prompted the need for simple analytical approximations that are valid over a wide range of outdoor conditions. In this paper, new equations are presented which model the fill factor explicitly as a function of irradiance and module temperature, and these equations are tested on outdoor performance data measured at ESTI for a poly-Si and thin-film CdTe module.
2006 IEEE 4th World Conference on Photovoltaic Energy Conference, 2006
Back-contact metal-wrap-through (MWT) solar cells are very attractive for implementation into ind... more Back-contact metal-wrap-through (MWT) solar cells are very attractive for implementation into industrial production lines. They combine the advantages of back-contact cells and the potential of easy integration into the production lines of standard cells. Nonetheless, they tend to show lower fill factors and open-circuit voltages than conventional cells. This is attributed to a non-linear shunt behavior under the emitter busbars
Conference Record of the Twenty-Ninth IEEE Photovoltaic Specialists Conference, 2002., 2002
This paper addresses the need for new junction separation techniques that are low-cost, selective... more This paper addresses the need for new junction separation techniques that are low-cost, selective, have a high throughput and high-yield. Pre- as well as post-diffusion selective approaches as integrated into an existing low cost screenprinted metallisation processing scheme are discussed and compared to state-of-the-art technology.
MRS Proceedings, 2001
ABSTRACT The measurement of quantum efficiency with bias voltage is a powerful tool to characteri... more ABSTRACT The measurement of quantum efficiency with bias voltage is a powerful tool to characterize CdTe/CdS solar cell. As the quantum efficiency changes drastically with bias it will be referred to as Apparent Quantum Efficiency AQE. The AQE gives insight to the spectral contents of the cell current and therefore resolves the spatial carrier collection in the cell at each working point. So it is possible to understand the influence of the junctions and changing resistances in the cell. The photoconductivity of CdS facilitates AQE well above unity, i.e. up to 100, at high forward bias. The spectral sensitivity of the CdS photoconductivity affects the cell current strongly. This can explain the dependence of fill factor and roll-over of the I-V characteristics on the spectral content of illumination. Further more back contact junction influence and defect related features, such as sub band gap generation, are evident in the AQE for high forward bias.
Proceedings of the IEEE, 1997
Approximately 2 billion people, mainly in Third World countries, are not connected to an electric... more Approximately 2 billion people, mainly in Third World countries, are not connected to an electric grid. The standard, centralized grid development is too expensive and time consuming to solve the energy demand problem. Therefore, there is a need for decentralized renewable energy sources. The main attractiveness of solar cells is that they generate electricity directly from sunlight and can be
Plasma Processes and Polymers, 2006
Summary: An interesting opportunity arises when two or more oxides are used as alloys in an attem... more Summary: An interesting opportunity arises when two or more oxides are used as alloys in an attempt to combine the desirable properties of several materials. These systems are predominantly non-stoichiometric, and in the case of two oxides, they are called pseudobinary alloys. ...
![Research paper thumbnail of Influence of stoichiometry of direct plasma-enhanced chemical vapor deposited SiN[sub x] films and silicon substrate surface roughness on surface passivation](https://attachments.academia-assets.com/47740467/thumbnails/1.jpg)
Journal of Applied Physics, 2005
In this article, we report on the use of direct plasma-enhanced chemical vapor deposited silicon ... more In this article, we report on the use of direct plasma-enhanced chemical vapor deposited silicon nitride ͑SiN x ͒ films deposited at low excitation frequency ͑440 kHz͒ on low-resistivity ͑1.5 ⍀ cm͒ p-type Czochralski silicon substrate surfaces with different textures, to elucidate the influence of microroughness of the substrate surface on the surface-passivating properties of thin SiN x films. Whereas flat surfaces get the best passivation from Si-rich SiN x films, the optimum passivation shifts towards stoichiometric nitride as the microroughness increases, which points to the increasing relative importance of a charge-induced field effect. When short high-temperature ͑firing͒ treatments are applied upon passivation layer deposition, the process window to yield good surface passivation broadens, although very Si-rich films tend to suffer from blistering.
... Quelle: Publ. in: Proceedings of the 22nd European Photovotlaic Solar Energy Conference, Mila... more ... Quelle: Publ. in: Proceedings of the 22nd European Photovotlaic Solar Energy Conference, Milan 2007. ... With improved firing conditions 17.9% in efficiency could be reached on 2x2 cm² EFG solar cells using a photolithography based solar cell process. ...
ABSTRACT Solar cells on thin (/spl les/150 /spl mu/m) multi-crystalline Si (mc-Si) substrates req... more ABSTRACT Solar cells on thin (/spl les/150 /spl mu/m) multi-crystalline Si (mc-Si) substrates require diffusion lengths exceeding twice the substrate-thickness combined with an excellent rear-surface passivation in order to reach efficiencies above 16%. Moreover, thin substrates no longer allow the use of screenprinted Al for back-surface-field (BSF) and contact formation, due to excessive warping upon firing. Gettering originating from POCl/sub 3/ emitter diffusion, is shown to enhance the bulk-quality to fulfill the first requirement. PECVD amorphous-Si (a-Si) layers, on the other hand, provide very low surface recombination rates. As a consequence, a POCl/sub 3/ diffused front emitter, combined with a heterostructure a-Si/mc-Si rearside is suggested to overcome the several constraints present when shifting to the use of thinner substrates within a low-cost environment.
… Platform, Office for …, 2007
1Address for correspondence: Energy research Centre of the Netherlands ECN, POB 1, NL-1755 ZG Pet... more 1Address for correspondence: Energy research Centre of the Netherlands ECN, POB 1, NL-1755 ZG Petten, The Netherlands. [email protected] ... ABSTRACT: The EU PV Technology Platform [1] aims at joining forces on a European level to contribute to the further development of ...
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Papers by Guido Agostinelli