Electrode substrate, method for manufacturing same, and biosensor using electrode substrate

An electrode substrate comprising:

• an insulating substrate having, on a surface thereof, a region where a fine uneven structure is formed and a plurality of smooth regions separated by the fine uneven structure;
• and
• a conductive thin film formed on an entirety of at least one surface of the insulating substrate where the fine uneven structure is formed,
• wherein the conductive thin film formed on the region where the fine uneven structure is formed is discontinuous,
• wherein the fine uneven structure region includes a plurality of protrusions discontinuous in at least one direction in a surface direction of the insulating substrate,
• wherein the plurality of protrusions discontinuous in the at least one direction include columnar bodies, and for each columnar body, an intersection angle X′ between a side of the columnar body in a longitudinal cross-sectional shape and a line on a surface of a bottom of the fine uneven structure is 85° to 90°,
• wherein each columnar body has a diagonal dimension of 10 to 50 nm and a height of 100 to 2000 nm, and the columnar bodies are disposed at intervals of 50 to 200 nm,
• wherein each columnar body includes a substantial cone or a substantial pyramid coupled to an upper surface of the columnar body, the substantial cone or the substantial pyramid having a bottom surface which has the same shape as the upper surface of the columnar body or which has an area smaller than that of the upper surface of the columnar body.