In-depth characterization of amorphous silicon/crystalline silicon junction-based solar cells comparison between low-cost prototypes and commercial technologies

Details

Supervisors

Flandre, Denis

Faculty

Ecole polytechnique de Louvain

Degree label

Master [120] : ingénieur civil électricien, à finalité spécialisée

Abstract

As climate change is one of the the greatest challenge of our time, renewable energies must be as green and accessible as possible. The company Maana Electric develops a solar cell technology that will reduce the amount of CO2 produced during the manufacture. This technology is based on a silicon heterojunction design consisting of amorphous silicon deposited on crystalline silicon. The purpose of this work is to measure and characterise this design in order to investigate its limitations, in particular between two cells of different efficiency and compare them to commercial cells. Thanks to a low-resistance setup, the characterisation is based on current-voltage measurements carried out under dark condition and with a temperature variation from 25°C to 100°C. In addition, admittance measurements were taken to complete the characterisation. The samples are analysed using a double diode model fitting and the physical phenomena are verified using SCAPS simulation. This work highlights a high performance fitting model which has shown that the primary limitation of the low-cost samples is the large shunt and series resistances. These large series resistances are responsible for the efficiency gap between the low-cost batches. The second limitation, although less significant, is the saturation current of the diffusion diode which contributes to the difference in efficiency between the commercial samples and the low-cost samples.