Patent ID: 8491853

Claim:
A substrate for bioassay, comprising: a first substrate having a group of reaction regions formed on an upper surface thereof and a group of information pits formed on a lower surface thereof, the group of information pits being used to obtain positional information of individual reaction regions and/or substance information used in the reaction regions, and the group of reaction regions and the group of information pits lying in a same optical path; a second substrate abutting the lower surface of the first substrate; a reflection film formed on the lower surface of the first substrate where the group of information pits are formed and bonded to an upper surface of the second substrate; a transparent electrode layer formed on the upper surface of the first substrate; and a conductive cover substrate disposed over the first substrate, the cover substrate including a plurality of holes corresponding in number to the reaction regions, and having an outer diameter smaller than the first substrate, wherein the conductive cover substrate is a counter electrode configured to apply an electric field to at least one of the group of reaction regions.