The obtained results are very promising for a transfer of the HIP-MWT concept to n-type silicon. Dark current-voltage characteristics in forward and reverse bias condition show quite different behavior for each of the six via pastes tested on p- and n-type test structures. The contact separation and minimum leakage current to the base has to be ensured by the non-contacting via paste itself. formation of the via paste to the base is also of particular interest since in more advanced MWT structures no rear emitter is present, as for example the high-performance MWT (HIPMWT) approach on p-type silicon. Five out of six via pastes investigated show average via resistances of less than 4 mΩ by using an appropriate suction process.
Processing make screen wrap around series#
Special attention has to be given to the right choice of both metallization paste and suction process, in order to ensure a low via-related series resistance. Via metallization is a main challenge in fabrication of metal wrap through (MWT) solar cells. IMEC sees a road to >21% efficient i-PERL solar cells in production. Latest results with average solar cell efficiencies of 20.4% over the length of a CZ-Si ingot with top efficiencies of 20.6% are just an intermediate step. Cu plated contacts show reliable module data in IEC test conditions. Fill factors of 80% have been achieved for fully screen printed (front and rear) solar cells with low cost rear side dielectric stack layers.
On large area homogeneous emitter CZ-Si solar cells FhG-SE Cal-Lab confirmed solar cell efficiencies of 20.0 and 20.3% for screen printed Ag and reliable plated Cu front contacts, respectively. Selected development results of this IIAP are presented here. the possibility to actively join development efforts with IMEC and other partners sending residents to work at IMEC as part of a research team. IMEC's Industrial Affiliate Programme (IIAP) offers industrial partners. In parallel simplifications and cost reductions were needed to bring it to production. Since then considerable improvements in solar cell efficiencies have been obtained with that type of process. An industrially applicable process flow for the formation of rear side passivated solar cells has been suggested by IMEC in 2005.
0 kommentar(er)
