Posted by Dan (66.122.81.186) on December 14, 2009 at 17:44:47:
In Reply to: emitter profile on acidic etched multi-Si wafer posted by Yunfei on December 14, 2009 at 07:35:12:
: Can you make a profile of emitter for production multi wafers? need profile depth of 0,7microns, wafer size 156*156mm2, square sheet about 60-65ohm/square, acidic etched wafer. or you may tell me how to provide the samples. Thanks!
If you have rough surface multi wafers such as those used in solar cells, the roughness would prohibit profiling any layers with junction depths less than the peak to valley roughness. We could do 4-point probe mapping of the entire cell and provide information about the uniformity. For depth profiling you would have to use mirror-polished wafers. Our technical page lists several notes on rough surface measurements.
If you have standard product wafers with multiple dice, provided the emitter area is at least 20 x 100um into a mirror-polished surface, yes we can depth profile the emitter. We need a width of at least 20um so both probes can be placed within the structure without shorting against each other. A length of 100um would be adequate if there is just the emitter into a background. 100um length would allow for marginal characterization if there were a base layer or well under the emitter and you want both layers detailed. Several hundred microns of length would be better. Our technical page has a depth resolution calculator that would provide information about the amount of resolution you would be able to get.