If we could etch a lot of material, there wouldn't be any issue of removing particles. But we can't etch very much, so now we've got to figure out how to provide physical energy to remove particles. And so it's that balance of providing enough physical force to remove particles during the cleaning process without damaging structures. |
The porous materials have some other issues with pore sealing, so then you have to worry about subsequent processing. Like liquid processes are going to penetrate the pores. |