Programm Photovoltaik Ausgabe 2008 ... - Bundesamt für Energie BFE

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Summary of Applied Materials Switzerland’s work within BiThink project:
The wafer thickness was decreased from 280�m down to 90�m. At the same time wire diameter was
reduced from standard 160�m to 120�m. The combined effects of wafer thickness and wire diameter
reductions yield an increased of Silicon usage by means of an increase of the number of wafers obtained
per linear meter of silicon loaded into a multi-wire saw. Figure 1 shows the overall achievement:
more than 3500 wafers per linear meter obtained in this work package.
Wafer/linear meter of Si
4000
3500
3000
2500
2000
0 5 10 15 20
Cut # in BITHINK project
Figure 1: Increased in the number of wafer produced per linear meter of Si
Cleaning and singulation feasibility for thin 120�m-thick wafers have been demonstrated.
The technology makes use of an original principle (patent pending) based on molecular interactions
(Van Der Waals forces). A prototype bench unit was built to present in time at the 21 st European Photovoltaics
& Solar Energy Conference and Exhibition held 4-8 September 2006 in Dresden (Germany).
Figure 2: Prototype built for demonstrating singulation capability of thin wafers
BiThink, P. Nasch, Applied Materials Switzerland
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