O2 etches photoresist very fast.

ÇÇ´óÓÂ wrote:

> I am using a RIE etcher to pattern polysilicon with SF6 & O2, and i observed
that
> after a long time etching, the color of the photoresist changed and under SEM,
the
> smooth surface of photoresist is replaced by a rough surface, would anybody
give
> an explanation of this phenomenon?