Spray-deposited CuIn_1−x Ga _x Se₂ solar cell absorbers: Influence of spray deposition parameters and crystallization promoters

Abstract

To produce smooth, crack-free, and highly crystalline absorber layers are the main challenges in the fabrication of thin film solar cells using nanoparticle-based solution-processing technologies. In this work, we report on the optimization of the spray deposition parameters to produce highly homogeneous CuIn 1Àx Ga x S 2 thin films with controlled thickness using nanoparticle-based inks. We further explore the use of inorganic ligand exchange strategies to introduce metal ions able to promote crystallization during the selenization of the layers, removing structural defects and grain boundaries that potentially act as recombination centers.

Electrodeposition of CuGaSe2 and CuGaS2 thin films for photovoltaic applications

“…They have a large optical absorption coefficient (10 5 cm -1 ) and have yielded highest conversion efficiencies among thin film technologies at laboratory scale [4,5,6].…”

Thin Film Solar Cells Based on Copper-Indiumgalium Selenide (Cigs) Materials Deposited by Electrochemical Techniques.

“…The formation of CuGaS2 thin films was evidenced by the by the displacement of the diffraction peaks of the CuGaSe2 towards higher angles to which makes the X-Ray diffraction 18 pattern which makes it coincide with the diffraction pattern of the CuGaSe2 films, and by the shift towards the blue (higher energies) of the optical gap. The optical gap found for the However, when neutral defects related to Cr-doping were introduced in the absorber layer, the positive effect of the enhancement of photon harvesting due to IGB was compensated by a decline in the carrier collection and the overall efficiency of the device fell considerably La obtención de dispositivos fotovoltaicos más eficientes y de bajo coste es uno de los desafíos tecnológicos más importantes de las últimas décadas.…”

“…Chalcopyrite Copper indium gallium diselenide Cu (ln, Ga)Se2 has an extremely high absorptivity (10 5 cm -1 ) at laboratory scale [18,19] Efforts to seek an economical and scalable method for the production of stoichiometric CIGS thin-films have been ongoing to appreciate the commercialization of these devices. Among several techniques, electrodeposition has demonstrated to produce CIGS devices with high efficiency [20] that allows 99% of the available incident light to be absorbed in the first micron of the material.…”

“…The high performance Cu(In,Ga)Se2 solar cell results so far have been reported on Cu(In,Ga)Se2 layers prepared by different techniques like, spray-deposition [48], low-temperature deposition. [49] by thermal co-evaporation onto heated substrates (400-600 Cº) [50] or by salinization processes.…”

“…Moreover, the alignment of the bottom of the conduction band between the absorbing chalcopyrite layer and the surrounding buffer and transparent conducting layers favors quick drift of the electrons in thin-film solar cell devices [75,76]. These chalcopyrite materials also exhibit a very large absorption coefficient of 10 5 (cm −1 ) above the absorption edge as opposed to the majority of the III−V semiconductors with absorption coefficients of 10 4 (cm −1 ) and have yielded highest conversion efficiencies among thin film technologies at laboratory scale [77,78,79]. The experimental apparatus described in Chapter 2 was used in this study.…”