However, this shrinkage region exhibited increased fragility under certain conditions. Treatments For efficient protein or linker binding, the exposed Au surface must be activated to ensure dense molecular coverage. However, O-plasma treatment was found to increase the roughness of the bottom Au electrode (Figure ). Comparative analysis revealed that for this purpose, mild base piranha was more effective than the O-plasma treatment (Figure ). Base piranha not only provided effective surface cleaning but also facilitated activating the Au surface while minimizing surface roughness. This process proved critical for achieving a clean, activated surface for subsequent linker or protein deposition.