Surface and bulk passivation of multicrystalline silicon solar cells by ...

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Figure 3.7 Measured Seff(Δn) dependence at the SiN X-passivated surfaces of three 1.5 (Ωcm
FZ p-Si wafers. The SiN X films were fabricated by three different PECVD
methods: low-frequency(100 kHz) direct PECVD, high-frequency (13.56
MHz) direct PECVD, and remote PECVD [56].
3.2.2.2 Seff dependence on resistivity. Figure3.8 shows the calculated S SA as a function of
the injection level Μ in the quasi neutral bulk for different wafer resistivities (1, 2, 3 and
5 Ω-cm) and p- and n-type silicon, respectively.
For model calculations, a typical set of parameters for the dielectric-Si interface
has been used. An interface state density, Dt of 5x10 10 cm 2 eV-1
, a positive fixed charge
Qfof 1x1011m-2 and capture cross-sections for electrons and holes of 10 14 and 10 -16cm2,
respectively, were taken from measurements reported in the literature [83]. Furthermore,
an assumption was made that the interface states were uniformly distributed across the
bandgap and that all states below midgap were donor-like states whereas all states above