I think you're going to find that as a standard practice.  Producing dice is not a cheap venture, requiring some pretty pricey equipment with fast devaluation times (particularly when it seems we're cutting feature size by 5% every month).  What quantities are you talking about?

Dan - Owner
http://www.Hi-TecDesigns.com

The quantity for each type of bare die is about 5,000/month. If you have some good sources, please let me know.

I'm surprised that Semidice won't talk to you.  5000/month is a fairly large number; we've purchased less than 1000 from them before, but that was a Loooong time ago.  You might try talking to the manufacturer's rep and see if they help out in some way.

TTFN

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Oh, I thought you were wanting a few hundred/month... as IR said, a few thousand/month should be acceptable for the smaller factory shops, particularly for something as simple as  transistors and diodes.  It's only a handful of processing steps, so they might even be able to process extra wafers at the end of a major run.  I've never worked with SemiDice, but I'm surprised you haven't found anyone willing to work with those numbers.

Dan - Owner
http://www.Hi-TecDesigns.com

See: http://www.infineon.com/cms/en/product/channel.html?channel=ff80808112ab681d0112ab6a748d050e