Research on the Influence of Czochralski Process Parameters on Oxygen Content of N-Type Monocrystalline Silicon

Abstract

Abstract: TOPCon cell substrates are dominated by N-type silicon wafers, and the oxygen content of N-type silicon wafers affects the conversion efficiency of TOPCon cells to a certain extent. In this paper, the Czochralski method was used to grow monocrystalline silicon, and the influence of crystal growth process parameters on the oxygen content of N-type monocrystalline silicon were studied by adjusting the crucible rotation rates, argon flow rates and furnace pressure. The numerical simulation analysis and experimental results show that: the accretion of crucible rotation rates can suppress buoyancy-thermal capillary vortices, reduce the volatilization of SiO at the melt interface, and increase the oxygen content in the silicon melt and in the monocrystalline silicon rods; increasing the argon flow rates and decreasing the furnace pressure can enlarge the mass flow rates of SiO at the melt interface, effectively promote SiO volatilization, reduce the oxygen content at the solid-liquid interface, and thus lessen the oxygen content in the monocrystalline silicon rods. The monocrystalline silicon oxygen content test and EL detection results show that, with the 5 r/min of crucible rotation rate, 100 L/min of argon flow rate, and 1 200 Pa of furnace pressure, the oxygen content in N-type monocrystalline silicon is the lowest, and the concentric circle ratio is also the lowest in the production of photovoltaic cells. The research in this paper can provide some ideas for reducing oxygen content in N-type monocrystalline silicon rods.

Key words: N-type monocrystalline silicon, reduction of oxygen content, crucible rotation rate, argon flow rate, furnace pressure, concentric circle

CLC Number:

O782

CHAI Chen, ZHANG Jun, WANG Yulong, HAN Qinghui, LI Huaiming. Research on the Influence of Czochralski Process Parameters on Oxygen Content of N-Type Monocrystalline Silicon[J]. JOURNAL OF SYNTHETIC CRYSTALS, 2024, 53(5): 792-802.

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