High Quality Antimony-Doped n-Type Silicon Wafers for Solar Cell Applications

This study explores the electronic properties of industrial antimony-doped (Sb-doped) n-type silicon wafers, grown using the Recharged Czochralski (RCz) method, for photovoltaic applications. We examine the resistivity distribution along the RCz grown ingots, bulk minority carrier lifetime, and bulk implied voltages at maximum power point (iVMPPbulk) and open-circuit (iVOC_bulk) conditions. The impact of phosphorus diffusion gettering treatments on wafer quality is evaluated, alongside a comparison of iron (Fe) gettering rates in Sb-doped and phosphorus-doped (P-doped) wafers. The results show that Sb-doped wafers grown via the RCz method demonstrate a very high material quality, with bulk lifetimes (tau bulk) and implied voltages approaching the Auger limit in the as-grown state, except for the final ingot near maximum power point conditions, which requires a gettering step to reach the Auger limit. Additionally, we confirm that the dopant distribution is significantly more uniform along the Sb-doped ingots than along comparable P-doped RCz ingots. Our findings also show that Fe gettering rates by the SiNx:H films for cumulative annealing at 325 degrees C in Sb-doped and P-doped RCz wafers are very similar. The high-quality and uniform doping of the Sb-doped ingots highlight their potential for high-efficiency silicon solar cell production, as well as possible improvements in ingot yield and cost-effectiveness.