Embedded noble metal electrodes in microfluidics

A method of manufacturing a nanogap, the method comprising:

• disposing an oxide layer on top of a substrate;
• disposing a release layer in a pattern on top of the oxide layer;
• etching a patterned trench into the oxide layer using the pattern of the release layer;
• disposing a metal layer on the release layer and in the patterned trench, such that the metal layer is disposed on top of the oxide layer in the patterned trench;
• performing a polish to remove the release layer, thereby removing both the release layer and a portion of the metal layer having been disposed on top of the release layer, such that the metal layer remaining includes a first metal part and a second metal part connected by a metal nanowire, wherein the metal layer remaining is coplanar with the oxide layer;
• forming a nanochannel in the oxide layer in a region of the metal nanowire, wherein the metal nanowire intersects the nanochannel;
• and
• forming the nanogap in the metal nanowire, such that the first metal part and the second metal part are separated by the nanogap, the nanogap being parallel to the nanochannel and perpendicular to the metal nanowire;
• wherein the nanogap, the metal part, the second metal part, and the nanochannel lie in a same plane.