In the recent years, it was reported that surface passivation of crystalline solar cell with aluminum oxide (Al2O3) deposited by atomic layer deposition (ALD) seems to be a good candidate for c-Si Solar cells for both n-type and p-type Si due to its very high negative fixed charge density (Qf ~ 1012-1013 cm-2) .
This paper assesses the study of passivation quality of different dielectrics. We have considered three different dielectric materials for this work namely: thermal SiO2(20nm), SiO2 deposited by plasma enhanced chemical vapor deposition (PECVD)(20nm), Al2O3 deposited by ALD with two different techniques (thermal(20nm) and plasma(15nm)). MOS-capacitors has been fabricated and characterized to extract the interface trap charge densities (Dit) at the silicon/dielectric interface, fixed charge (Qf) in the dielectric and life time measurements were also performed with quasi-steady-state photo-conductance decay , transient techniques