Investigation of various surface passivation layers using oxide/nitride stacks of silicon solar cells

In this work, three different surface passivation technologies are used: classical thermal oxidation (CTO), rapid thermal oxidation (RTO) and silicon nitride using PECVD. Eight combined passivation schemes including SiO/sub 2//SiN/sub x/ stacks are investigated on 1 /spl Omega/cm FZ silicon without and with emitter (100 /spl Omega///spl square/ and 40 /spl Omega///spl square/). SiO/sub 2//SiN/sub x/ stack passivation results in excellent lifetime of 1361 /spl mu/s without emitter and shows as a good passivation quality as CTO (300-400 /spl mu/s) for 100 /spl Omega///spl square/ emitter. The RTO/SiN/sub x/ stack layers are used to passivate front and rear surfaces of the solar cells. The planar RTO/SiN/sub x/ cell has a very high V/sub oc/ of 675.6 mV. However, the J/sub sc/ and FF of the RTO/SiN/sub x/ cells are lower than those of CTO cells. The main reasons of J/sub sc/ and FF losses are also discussed.