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Ion implantation is the technique of choice for introducing dopant species into semiconductors in CMOS devices.In photovoltaics ion implantation was used for high efficiency silicon solar cells already in the 1980ies.Currently we are experiencing a renaissance of this exciting technique which could be an interesting alternative to tube furnace diffusion processes.Ion implantation inherently is a single side process which can be easily masked by shadow masks or by a simple resist.Other beneficial features of the implantation process are that no doped glass (PSG,BSG) is formed during the doping process and that implantation is a low temperature process that allows independent optimization of differently doped areas.Several recent investigations have shown that the damage introduced during implantation can be completely removed during annealing and that a co-annealing process can be applied for the annealing of boron and phosphorus profiles.At Fraunhofer ISE we have achieved solar cell efficiencies exceeding 22% with impressive open-circuit voltages of 694 mV.This presentation gives an overview over ion implantation at Fraunhofer ISE,at other research institutes and in industrial application.