SMART Cast-Monocrystalline p-Type Silicon Passivated Emitter and Rear Cells: Efficiency Benchmark and Bulk Lifetime Analysis

Herein, boron-doped cast-monocrystalline silicon wafers that have been fabricated using the Seed Manipulation for ARtificially controlled defect Technique (SMART mono-Si) are examined. Their suitability for passivated emitter and rear cell (PERC) fabrication is investigated. Applying a zero busbar layout energy conversion efficiencies of eta = 21.9% for SMART mono-Si, eta = 22.2% for gallium-doped Cz-Si (Cz-Si:Ga), and eta = 22.3% for boron-doped Cz-Si (Cz-Si:B) are achieved at similar doping levels between 0.7 omega cm <= rho(B) <= 1.0 omega cm. Therefore, SMART mono-Si PERCs show almost the same performance as Cz-Si PERCs. Apart from the performance of SMART mono-Si PERCs, the minority charge carrier bulk lifetime tau(B) of the SMART mono-Si wafers after different high-temperature process steps in the PERC process flow is investigated. After emitter formation, this analysis confirms the high material quality of SMART mono-Si yielding tau(B) approximate to 1.3 ms at an injection level of Delta n = 10(15) cm(-3). The bulk lifetime after firing is similar to the level determined for mCz-Si:B and Cz-Si:Ga reference wafers of similar doping level.

Automated summary

This study examines boron-doped cast-monocrystalline silicon wafers fabricated using the Seed Manipulation for ARtificially controlled defect Technique (SMART mono-Si) for passivated emitter and rear cell (PERC) fabrication. The research found that SMART mono-Si PERCs exhibit almost the same performance as traditional Cz-Si PERCs. Additionally, the investigation showed that the minority charge carrier bulk lifetime of SMART mono-Si wafers remains high after different high-temperature process steps in the PERC process flow.