Fractured metal on a 0.2 micron Polyimide released layer
Michael D Martin
2003-09-19
We have been trying to release a 0.2 micron thick layer of polyimide
over a silicon frame with a diameter of 100 - 500 microns. The layers
from top to bottom are metal 0.1 microns thick (Al or Cr) unpatterned,
polyimide, silicon dioxide (0.5- 1 microns), and a 300 micron thick
wafer. The etching is done by DRIE with the oxide as a stop layer. We
notice cracking in the metal layer after release. Has anyone had this
problem? Any suggestions will be appreciated.
Thanks in advance,
Mike Martin
U. of Louisville