A low-cost laser grooved interdigitated back contact solar cell

Abstract

Work into the interdigitated back contact (IBC) cell to date has shown that the geometry can produce amongst the highest efficiency silicon solar cells. These current devices have yet to become the market leading technology due to the costly and tricky fabrication processes required to keep the doped regions of the p/n junction separate from each other whilst being on the same side of the wafer. This project will demonstrate a novel approach using lasers to create deep surface grooves to allow localised doped regions on a single wafer surface. The purpose of this is to shorten the current path between the charge generation and charge collection regions, although potential benefits of this approach may be limited by increased recombination as a result of enlarging the metal-silicon contact area. Laser processing is however a very cheap and fast method that will allow a significant reduction in processing costs for IBC cells. In this project, an initial crude proof of concept device with an efficiency approaching 1% was fabricated. This served to prove that the novel geometry proposed by this project could create a working device. Technology Computer Aided Design (TCAD) modelling was carried out, showing that with further processing steps and Table of Contents iii optimisation of existing ones, devices with efficiencies exceeding 20.5% could potentially be created. Further experimental work was then performed to develop processes needed for the fabrication of the improved device design as modelled. In summary, the ability to utilise lower cost fabrication methods involving laser processing to produce highly efficient device geometries represents a promising approach to reducing the cost per watt of solar renewable energy.

More information

Identifiers

ORCID for Wassim Javade Mughal: orcid.org/0000-0002-8457-1753

ORCID for Stuart Boden: orcid.org/0000-0002-4232-1828

Catalogue record

Export record