I am looking for a thick polyimide (100-200 um in a single spin-coating)
to use in a millimeter-wave circuit application.  However, I would like
the dielectric constant to be as high as possible.  Does anyone know of
a thick, high-k polyimide or similar spin-on insulating polymer?  Or do
polyimides never get above k=4 or so?

Marc DeVincentis
UCLA