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PERC (Passivated Emitter and Rear Cell) technology has been established as a new standard in silicon PV cell manufacturing whereby the deposition of the aluminum oxide (AlOx)/silicon nitride (SiNx) rear-side passivation stack is mainly performed by inline PECVD equipment. Simultaneously the industrial price pressure for cell and module manufactures increase by lower module prices. Thus further reductions of production costs per watt peak (Wp) are required. For this reason manufacturing equipment with higher throughput as well as a lower OPEX (operational expenditure) combined with high tool uptime and yield keeps being mandatory. PV tool suppliers are focused on developing new tool generations to meet those requirements by also supporting new cell technology improvements at once. Beside wet chemistry, diffusion and metallization tools especially new high quality and high-throughput passivation concepts for enhanced PERC (PERC+ [4]) cells are necessary. This paper shows results on Meyer Burgers new PECVD passivation equipment for enhanced PERC}+ cells including technologies like selective emitter and emitter oxidation. Those new passivation concepts can be applied for only rear side (MAiA ® 6.1) and even both sides (FABiA ® 4.1) of a PERC+ cell with throughputs up to 6000W/h and excellent deposition uniformity and quality.

In this paper the novel method MDP (microwave detected photoconductivity) [1–4] will be introduced to the field of contact less inline metrology at bricks. By the application of a widely advanced microwave detection technique, it is now possible to map minority carrier lifetime and photoconductivity simultaneously, with a so far unsurpassed combination of spatial resolution, sensitivity, and measurement speed. Beside these two parameters the iron concentration can be detected and analyzing the photoconductivity at steady state in comparison with the minority carrier lifetime, a lot of additional information can be derived. This paper will show first examples of minority carrier lifetime and photoconductivity maps, along with resistivity linescans and iron concentration maps of whole bricks measured inline. Furthermore simulations will be provided. Solving the transport equations for electrons and holes during the measurement at bricks, it can be proven that the measured effective lifetime deviates only lightly from the actual bulk lifetime. Furthermore it becomes clear that a steady state generation is more suited for brick measurements than non-steady state methods.