For thin-film crystalline Si solar cells on glass, metallisation is the key to converting what is otherwise a large-area diode, into a true photovoltaic device. The goal of metallisation is to produce devices with as high efficiencies and as little parasitic losses as possible. This is the inspiration here, where the metallisation of crystallised Si material deposited by plasma-enhanced chemical vapour deposition (PECVD) is of particular interest. The metallisation investigated is based on an interdigitated scheme, where the positive and negative electrodes of the device form a comb-like structure on the cell surface. This unique structure allows for a variety of investigations to take place aimed at both improving understanding of the scheme, and exploring methods to further increase efficiencies of metallised devices. The results are structured into three main parts. In the first part, power loss formulas, both absolute and normalised, were derived for the interdigitated-on-glass device structure. This allows for the characterisation and identification of the various resistive and shadow losses associated with metallisation. Optimal metallisation patterns were then realised by minimising these power losses. The second part involves metallisation itself, where device fabrication, sidewall formation, and the impact of thermal annealing were investigated. High-rate PECVD (>200 nm/min) was introduced as a means of combating one of the main drawbacks of PECVD. An efficiency of 5.9 % was obtained on this material - the first reported result for high-rate PECVD poly-Si thin-films on glass. In the third part, the concept of cell tabbing and interconnection using wire-bonding was developed. Both tabbing of individual cells and interconnection to form mini-modules were found to significantly reduce series resistance, boosting fill factors and efficiencies of metallised devices. An 8.05 % efficient individual cell and an 8.28 % two-cell mini-module were fabricated using this technique.Power loss formulas are derived, further insights into metallisation are presented, and the successful series-interconnection of cells has taken place. There is considerable scope for further improvements in device efficiency from metallisation, via the simultaneous consideration and implementation of multiple results found in this thesis: optimal metallisation patterns, post-metallisation annealing, wire-bonding tabbing/interconnection and encapsulation.
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