Solar cells structure

Electrolyte contacts have been used to characterize as-deposited and annealed CdS/CdTe solar cell structures by photocurrent spectroscopy and electrolyte elec-troabsorbance/electroreflectance measurements (EEA/EER) [267-269]. 

The in-line configuration consists of deposition chambers that are separated by isolation chambers [153]. The layer sequence of a solar cell structure prescribes the actual sequence of deposition chambers. The flexibility is much less than with a cluster configuration, and costs are generally much higher, but the throughput can also be much larger. In an in-line system the substrates can move while deposition takes place, which leads to very uniformly deposited layers, as uniformity of deposition is required only in one dimension (perpendicular to the moving direction). 

FIG. 72. Schematic cross-section of (a) a single junction p-i-n o-Si H superstrata solar cell and (b) a tandem solar cell structure. (From R. E. I, Schropp and M. Zeman. "Amorphous and Microcrystalline Silicon Solar Cells—Modeling, Materials and Device Technology," Kluwer Academic Publishers, Boston, 1998, with permission.)... 

A schematic cross-section of a p-i-n a-Si H solar cell [11] is shown in Figure 72a. In this so-called superstrate configuration (the light is incident from above), the material onto which the solar cell structure is deposited, usually glass, also serves as a window to the cell. In a substrate configuration the carrier onto which the solar cell structure is deposited forms the back side of the solar cell. The carrier usually is stainless steel, but flexible materials such as metal-coated polymer foil (e.g. polyimid) ora very thin metal make the whole structure flexible [11]. 

Incorporated in a device, the LPCVD -Si H material shows electroluminescence only in reverse bias [673]. The mechanism is similar to the one described for c-Si. The PECVD a-Si H material was incorporated in a p-i-n solar cell structure, with a thickness of the intrinsic layer of 500 nm (see Section 1.11.1). Oxygen was coimplanted at 80 keV (3.2 x 10 O/em-) and at 120 keV (5.5 x lO 0/cm ), which resulted in a roughly constant oxygen concentration of 1.0% in the Er projected range in the middle of the intrinsic a-Si H layer. Electroluminescence is observed under forward bias [674]. 

ZnO films can provide substantial information on chemical and electronic properties of ZnO surfaces and interfaces, which occur in real thin film solar cell structures. In addition, general information on the interface formation of oxide materials can be extracted. In the following we describe ... 

Fig. 8.4. Layer structure of single junction n-i-p (substrate) and p-i-n (superstrate) solar cells. Also included is an amorphous/microcrystalline tandem solar cell structure...

Fig. 4.9. Energy diagram of the ideal solar cell structure in Fig. 4.5 absorber between an n- and a p-membrane [6]. Electrons can be exchanged through the n-membrane, while holes are blocked by a barrier in the valence band. Holes can only be exchanged through the p-membrane, while electrons are blocked by a barrier in the conduction band...

Deposition technique Solar-cell structure >/(%) Reference... 

Fig. 6. (a) A p-i-n solar-cell structure on a glass substrate, (b) A p-i-n solar-cell structure on a steel substrate. 

Fig. 1 Buried contact solar cell structure, an important wafer-based commercial silicon cell technology. Features include surface texturing for light trapping, diffusions front and rear and the front current grid buried in laser grooves. (Courtesy of UNSW Centre for Photovoltaic Engineering Image Library.)...

Figure 7.10 Tandem solar cell structure for polymer blend solar cells, based on the design demonstrated by Hadipour et al. (2006). In this all-solution-processed device, the top cell consists of a polymer PCBM bulk heterojunction with an absorption maximum of 550 nm and preferentially absorbs short-wavelength light, while the bottom cell is made from a bulk heterojunction of PCBM with a red-absortring polymer and absorbs longer-wavelength light. The composite gold-PEDOT PSS internal layer connects the two cells in...

Transparent polymer solar cells (i.e., polymer solar cells with transparent electrodes) can be easily fabricated based on inverted architecture and have important application in tandem architectures as well. We can form transparent solar cells by replacing the Al top electrode with 12 nm Au in the inverted structure. The J-V curves for this transparent polymer solar cell, with light incident from ITO and Au side, are shown in Figure 11.17. The difference between the two J-V curves is due to the partial loss by the reflection and absorption at the semitransparent Au electrode. To provide sufficient electrical conductance, Au layer thickness has to be sufficient and the optical loss at Au electrode becomes significant. However, the inverted solar cell structure has the V2O5 layer which is not only transparent but also provides effective protection to the polymer layer. A transparent conductive oxides electrode, such as ITO, can therefore be deposited without compromising device performance. 

Yerokhov, V. Yu. and Mehiyk I. I. Eorous silicon in solar cell structures , (1999) Renew. Sust. Energ. Rev. 3,291-322. 

Previous sections present variety of solar cell structure and their corresponding elements and power conversion performance to indicate... 

Yerokhov VY, Melnyk I (1999) Porous silicon in solar cell structures a review of achievements and modem directions of further use. Renew Sustain Energy Rev 3 291-322... 

If a lightly doped - 10 Q cm p-type substrate is used the inherent interface charge will induce an n-type surface inversion layer to which contact may be made by means of a fine grid to form a solar cell structure simular to that shown in Figure 21. 

Figure 21. Inversion layer solar cell structure. (Ref. 58)...

III. DESIGN OF AN OPTIMIZED SOLAR CELL STRUCTURE FOR TANDEM CELL SYSTEMS... 

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