TY - GEN
T1 - Gettering and poisoning of silicon wafers by phosphorus diffused layers
AU - Macdonald, D.
AU - Cheung, A.
AU - Cuevas, A.
PY - 2003
Y1 - 2003
N2 - The effectiveness of phosphorus gettering, and the possible re-injection of impurities from the gettering layer during subsequent annealing, has been studied through the use of float-zone samples deliberately contaminated with iron. Lifetime measurements reveal that phosphorus gettering, in this case at 880°C, initially removes more than 99% of the iron from the wafer bulk, to levels below 1×1011cm-3. However, upon further annealing at temperatures greater than the gettering temperature, some of the iron is injected back into the wafer. Annealing at 900°C caused a significant amount of this 'poisoning', with 7% of the pregettered iron returning to the bulk, resulting in a final Fe concentration around 5×1011cm-3. At 800°C there was no detectable re-injection of Fe within uncertainty. The results may have implications for optimising industrial metallisation fire-through processes for multicrystalline solar cells, which contain relatively high levels of iron and other metal impurities.
AB - The effectiveness of phosphorus gettering, and the possible re-injection of impurities from the gettering layer during subsequent annealing, has been studied through the use of float-zone samples deliberately contaminated with iron. Lifetime measurements reveal that phosphorus gettering, in this case at 880°C, initially removes more than 99% of the iron from the wafer bulk, to levels below 1×1011cm-3. However, upon further annealing at temperatures greater than the gettering temperature, some of the iron is injected back into the wafer. Annealing at 900°C caused a significant amount of this 'poisoning', with 7% of the pregettered iron returning to the bulk, resulting in a final Fe concentration around 5×1011cm-3. At 800°C there was no detectable re-injection of Fe within uncertainty. The results may have implications for optimising industrial metallisation fire-through processes for multicrystalline solar cells, which contain relatively high levels of iron and other metal impurities.
UR - http://www.scopus.com/inward/record.url?scp=6344233761&partnerID=8YFLogxK
M3 - Conference contribution
SN - 4990181603
SN - 9784990181604
T3 - Proceedings of the 3rd World Conference on Photovoltaic Energy Conversion
SP - 1336
EP - 1339
BT - Proceddings of the 3rd World Conference on Photovoltaic Energy Conversion
A2 - Kurokawa, K.
A2 - Kazmerski, L.L.
A2 - McNeils, B.
A2 - Yamaguchi, M.
A2 - Wronski, C.
T2 - Proceddings of the 3rd World Conference on Photovoltaic Energy Conversion
Y2 - 11 May 2003 through 18 May 2003
ER -