Abstract
Low frequency direct plasma-enhanced chemical vapor deposited
Si
-
SiN
x
interface properties with and without
NH
3
plasma pretreatment, with and without rapid thermal annealing (RTA) have been investigated with deep-level transient spectroscopy (DLTS) on both n- and p-type monocrystalline silicon samples. It is shown that four different defect states are identified at the
Si
-
SiN
x
interface. Energy-dependent electron and hole capture cross sections were also measured by small-pulse DLTS. Samples with plasma
NH
3
pretreatment and RTA show the lowest DLTS signals, which suggest the lowest overall interface states density. Moreover,
SiN
x
with RTA passivates interface states more efficiently in n-type Si compared with p-type Si; also the deep-level parameters change in n-type Si but not in p-type Si. The combination of plasma
NH
3
pretreatment and RTA is suggested for application in the solar cell fabrication.