Nickel silicide contact for copper plated silicon solar cells
Document
Description
Nickel-Copper metallization for silicon solar cells offers a cost effective alternative to
traditional screen printed silver paste technology. The main objective of this work is to
study the formation of nickel silicide contacts with and without native silicon dioxide SiO2.
The effect of native SiO2 on the silicide formation has been studied using Raman
spectroscopy, Rutherford backscattering spectrometry and sheet resistance
measurements which shows that SiO
2
acts as a diffusion barrier for silicidation at low
temperatures of 350°C. At 400°C the presence of SiO2 results in the increased formation
of nickel mono-silicide phase with reduced thickness when compared to samples without
any native oxide. Pre and post-anneal measurements of Suns Voc, photoluminescence and
Illuminated lock in thermography show effect of annealing on electrical characteristics of
the device. The presence of native oxide is found to prevent degradation of the solar cells
when compared to cells without any native oxide. A process flow for fabricating silicon
solar cells using light induced plating of nickel and copper with and without native oxide
(SiO2) has been developed and cell results for devices fabricated on 156mm wafers have
been discussed.
traditional screen printed silver paste technology. The main objective of this work is to
study the formation of nickel silicide contacts with and without native silicon dioxide SiO2.
The effect of native SiO2 on the silicide formation has been studied using Raman
spectroscopy, Rutherford backscattering spectrometry and sheet resistance
measurements which shows that SiO
2
acts as a diffusion barrier for silicidation at low
temperatures of 350°C. At 400°C the presence of SiO2 results in the increased formation
of nickel mono-silicide phase with reduced thickness when compared to samples without
any native oxide. Pre and post-anneal measurements of Suns Voc, photoluminescence and
Illuminated lock in thermography show effect of annealing on electrical characteristics of
the device. The presence of native oxide is found to prevent degradation of the solar cells
when compared to cells without any native oxide. A process flow for fabricating silicon
solar cells using light induced plating of nickel and copper with and without native oxide
(SiO2) has been developed and cell results for devices fabricated on 156mm wafers have
been discussed.