To clarify, the text width in the Y and Z axes is 0.4 mm and it perforates a thin wall? Is the thin wall in contact with the build table? i.e. is the perforated thin wall the first layer? It seems like it from your image.

I see a couple of issues here that might interfere with the quality of outcome. First the X-Y resolution of your machine needs to be really good to make 0.4 mm wide perforations form well – I’d increase this to somewhere above 0.6 mm, maybe 1 mm if you can. It isn’t the fine holes you’d like but it will print much better. If you go to tooling, you can reduce the text coarseness. Second I’d put this on a raft, so the inaccuracy of the first layer does not affect the perforations forming.