Characterization and removal of polysilicon residue during wet etching
We presented 2 models on the residues generated at the Si wet etching. The residues of tornado shape make on hydrophobic surface due to poor wettability. We found the optimized surface through the contact angle. Hydrogen bubble generated during silicon wet etching causes significant residues. Ultrasonication or adding IPA is effective for preventing the bubble effect.
polysilicon wet etching hydrogen bubble alkaline chemicals hydrophilic