Esteban,
Are you using a Dicing saw to make the 10x20m sections ?  If you are
trying another mechanical scribe/break or other- it is likely that the
thin Si is just too fragile to facilitate a clean cut with your method.
Suggest using Diamond Saw Dicing with the 30um wafer on 'tape' to give
it the structural control to allow the cutting. There are several
services that can do this process for you - if you do not have dicing
capability in house.
Regards
Ken

Esteban Broitman wrote:
> Does anybody know how to "cleave" ultra thin Si wafers?
> I need to cut, from ultra-thin (30 microns) Si wafers, substrates of ~
> 10 x 20 mm. I tried to use different kind of diamonds, but I always have
> the same problem: the substrate is not more "flexible", if I try to bent
> it, it cracks in many parts. I suspect that I am generating defects
> during the cutting of the substrates that propagate during the bending.
> Any suggestion?.
> Thanks for the reply to my e-mail: [email protected]
> E. Broitman
> ----------------------------------
> Dr. Esteban Broitman
> Senior Research Associate
> Department of Chemical Engineering
> Carnegie Mellon University
> Pittsburgh,  PA 15213
> Phone: (412) 268-9537
> FAX: (412) 268-7139

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