Integrated biosensor structure and manufacturing method thereof

An integrated biosensor structure, comprising:

• a substrate having a first surface, the substrate comprises:
• a sensing region, comprising:
• a plurality of first doped regions at the first surface of the substrate;
• and
• a sensing oxide layer over the plurality of first doped regions, wherein the sensing oxide layer and the first surface of the substrate are free from having a metallization structure therebetween;
• and
• a logic region surrounding the sensing region, comprising:
• a plurality of second doped regions at the first surface of the substrate;
• a plurality of gate structures over the plurality of second doped regions;
• and
• a metallization structure over the plurality of gate structures.

A method of manufacturing an integrated biosensor structure, the method comprising:

• receiving a substrate having a first gate oxide and a second gate oxide over a first surface of the substrate;
• forming a plurality of first doped regions and a plurality of second doped regions at the first surface of the substrate;
• thinning downing the first gate oxide;
• forming a silicide layer over the second gate oxide and the plurality of second doped regions;
• forming a metallization structure over the plurality of second doped regions, the plurality of first doped regions are covered by a dielectric material of the metallization structure;
• etching the dielectric material of the metallization structure to form a first trench to expose the plurality of first doped regions;
• and
• forming a sensing oxide layer over the plurality of first doped regions.