US Patent 10586697 Wet strippable OPL using reversible UV crosslinking and de-crosslinking

Embodiments of the present invention are directed to the wet stripping of an organic planarization layer (OPL) using reversible UV crosslinking and de-crosslinking. In a non-limiting embodiment of the invention, an interlayer dielectric is formed over a substrate. A trench is formed in the interlayer dielectric. A work function metal is formed over the interlayer dielectric such that a portion of the work function metal partially fills the trench. A UV sensitive OPL is formed over the work function metal such that a portion of the UV sensitive OPL fills the trench. The UV sensitive OPL can be crosslinked by applying light at a first UV frequency and de-crosslinked by applying light at a second UV frequency.