Daniele Menossi

Electrical characterization and aging of CdTe thin film solar cells with Bi 2 Te 3 back contact

Despite CdTe solar cells have been already industrialized in large scale and modules are already available in the market, still the research for a stable, low cost, high performing back contact is very hot topic. As a matter of fact, it has been shown that the presence of copper in the CdTe device increases efficiency, not only by improving the back contact but also by doping the absorber and enhancing all the electrical properties. However copper is well known to be a degrading element in the device, diffusing down to the front contact. In this paper we present an electrical study and aging tests of a CdTe devices where copper is encapsulated within a Bi2Te3 buffer layer. The solar cells show a remarkable stability and a good efficiency.

Optimization of pulsed fiber laser scribing for CdTe and CIGS solar cells

The FP7 EU funded ALPINE project is focused on the processing of new type of thin film CdTe and CIGS photovoltaic modules by means of pulsed fiber laser scribing. The latest results of scribing tests performed for different laser parameters for P1, P2 and P3 steps in both CdTe and CIGS solar cells are discussed showing examples for CdTe module processing.

CIGS thin films prepared by sputtering and selenization by using In 2 Se 3 , Ga 2 Se 3 and Cu as sputtering targets

CuInGaSe<inf>2</inf>/CdS thin film solar cells were prepared by using a novel precursor obtained by depositing in sequence, on top of a Mo covered soda lime glass, In<inf>2</inf>Se<inf>3</inf>, Ga<inf>2</inf>Se<inf>3</inf> and Cu. A subsequent few minutes selenization of the precursor in a selenium vapor is sufficient to obtain a good quality CuInGaSe<inf>2</inf> film.

Laser scribing of CIGS based thin films solar cells

Laser scribing tests on CIGS based thin films solar cells have been performed. The obtained high quality incisions show that laser scribing is a valuable tool for producing low-cost photovoltaic modules.

Laser scribing integration of polycrystalline thin film solar cells

The growing demand for high productivity in the thin-film photovoltaic module industry, together with the request for more and more efficient devices, needs high-performance laser-scribing. The results of scribing tests on CdTe and CIGS solar cells samples are here presented. A comparison between the scribes obtained with ns regime fiber lasers, and a ps regime diode pumped solid state laser will be also reported.