An overview of currently used cell processes for monocrystalline silicon in industry is given. Since thescreen printed solar cell process has the biggest market share, advanced screen printing processes are presented. Thefront-side with selective emitter structures are investigated by measuring the emitter saturation current (j_(0e)) onsymmetrical test samples with QSSPC. The reference sample with an industrial homogeneous 50 Ω/□ emitter andfired PECVD SiN has a j_(0e) of 220 fA/cm~2. On selective emitter structures with two diffusion steps, using first a 100Ω/□ diffusion then a SiN layer as mask and finally a 10 Ω/□ diffusion, j_(0e) is 140 fA/cm~2 using PECVD SiN and 120fA/cm~2 respectively with LPCVD SiN. By changing the sequence of light and heavy diffusion and applying PECVDSiN for surface passivation, j_(0e) was measured to 90 fA/cm~2. Solar cells were made with a two step selective emitterand a simplified process with a single diffusion step using laser structured SiN as diffusion suppressing layer and notexture was applied to these cells. The best reference cell with homogeneous 50 Ω/□ emitter has an efficiency of16.2% and 625 mV V_(OC). The best selective emitter solar cells with both used processes have a 10 mV increase ofVOC leading to 635 mV and an efficiency of 17.0% of a cell using the simplified selective emitter process. The bulklifetime of Cz-Si was monitored during a selective emitter process with a screen printed aluminium BSF on the rear.The bulk lifetime of the as grown wafer was 32 μs and was subsequently improved by phosphorous gettering to 67μs. Bulk lifetime was further raised to 120 μs through aluminum gettering of the screen printed BSF. This result hasto be taken into account when applying alternative rear sides with dielectric passivation where beneficial aluminiumgettering cannot be used. Therefore material that does not strongly depend on aluminum gettering should be used. Adielectric rear side passivation can be integrated at several stages in the production process. Each sequence entailsdifferent challenges especially in maintaining the rear side passivation quality at the end of the process.
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