[10p-N304-1~7] 16.3 Bulk, thin-film and other silicon-based solar cells

1:30 PM - 1:45 PM JST(4:30 AM - 4:45 AM UTC)

[10p-N304-1] 3D distribution of sodium impurities in PID degraded Si solar cells determined by atom probe tomography

〇Yutaka Ohno¹, Koji Inoue¹, Yiming Qin², Fumihiko Uesugi³, Kazuhiro Gotoh^2,4, Atsushi Masuda^2,4 (1.IMR, Tohoku Univ., 2.Fac. Eng., Niigata Univ., 3.NIMS, 4.IRCNT,Niigata Univ.)

Keywords:

PID,Si solar cells,sodium impurities

An accelerated potential-induced degradation (PID) test was conducted on a Si solar cell module. A needle-shaped specimen including the SiN anti-reflection coating and the Si solar cell was prepared using a SEM-FIB technique. The three-dimensional atom probe tomography (3D-APT) analysis revealed the spatial distribution of sodium (Na) impurities. A high concentration of Na was observed to accumulate just beneath the ~100 nm-thick SiN layer, at the SiN/Si interface. The Na concentration decreased with increasing depth from the interface and remained detectable down to the vicinity of the pn junction, located approximately 100 nm below the interface.