Don,

Scotch tape will leave some glue residue on the chip. Over time dirt and dust will stick to the residue and degrade the condition of the chip.

There is a much easier solution. Put the chip into a 2.5" cardboard flip, or even just a plastic flip, to hold the chip straight when scanning. The scanner will see through the flip without any distortion giving you an excellent scan. I have scanned 100's of chips this way and have great results.