UV-Ozone Oxide layer for Junction Passivation and Passivating Contact Process of Silicon Solar Cells

We experimentally proved an effective use of UV-ozone oxide layer in junction passivation and current tunneling applications of crystalline silicon (c-Si) solar cells. The UV-ozone generated oxide layer can improve the passivation quality of aluminum oxide(AlO
x
) when inserted between the silicon wafer surface and atomic layer deposited(ALD) AlO
x
. When tested on junctions that moderately diffused by phosphorus and boron (sheet resistance R
sh
~110 Ω/□), the UV-ozone oxide and AlO
x
stack resulted in a J
0
no more than 12fA/cm
²
. The same oxide layer is also considered as a passivating contact material. When applied as an interlayer between diffused silicon surface and aluminum contact, the passivated contact structure realized a contact resistivity (ρ
c
) of ~ 1mΩ-cm
²
and ~ 25mΩ-cm
²
for boron and phosphorus passivating contact structures, respectively, with moderately doped diffusions.