Polyimide cutting

[Bostjan]

Hi,
I would like to cut a 200 micrometer thick Kapton polyimide with a UV
frequency tripled Nd:YAG laser. Before buying an expensive laser I am
trying to get as much information as possible about the cutting process so
that I would be able to pick the right source.
Let us say that I am cutting at 10 kHz pulse rep. rate:
If the pick power in the pulse is so high that plasma is formed than the
absorption in the cloud above the material will drastically increase. In
this case a source with 1.5 W UV average power at 10kHz and 100 ns long
pulses would be for example much better than a source with 1.5W power at
10kHz with 40 ns long pulses since cutting with short pulses and higher
pick power would be less efficient.
Another chance is that pulse length makes no big difference (no nonlinear
absorption effect is present). Than it might just be important to bring
energy in to the material in small packages and to leave some time between
this packages for the evaporated material to be blown away from the
illuminated spot. In this case it might be the most important to find the
source which gives the highest average power at 20 kHz or more regardless
of
the pulse length.
I would appreciate any suggestion very much.

Best regards, Bostjan