It was achieved by a two-layer metal deposition process on the protein-modified micropore device. This was done with a precisely aligned shadow mask positioned at the center of the active region of the micropore chip, exposing all protein-coated micropore windows. Metal layers were deposited sequentially using an Angstrom e-beam evaporator, with a 35 nm palladium (Pd) layer followed by a 25 nm gold (Au) layer. The micropore chip was mounted on the sample stage at a 45° inclination (for the indirect exposure of protein voids towards evaporated metal-vapor) during the deposition process; the sample stage temperature was maintained at 18°C through active cooling, with a rotational speed of 10 rpm. The chamber vacuum was maintained below 10 -7 torr and a 500 mm sample-target distance throughout the deposition.