Patent ID: 11860120
Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD.
Field: Measurement (Instruments)
Classification: CPC G  H | IPC G  H

Claim 0:
1. A method, comprising:
forming a semiconductor-on-insulator (SOI) substrate comprising a semiconductor substrate, a sacrificial substrate and a dielectric layer between the semiconductor substrate and the sacrificial substrate;
forming a plurality of sensing pixels in the semiconductor substrate, wherein forming each of the sensing pixels comprises:
forming source/drain regions in the semiconductor substrate; and
forming a temperature-sensing device in the semiconductor substrate;
forming a plurality of first elongated heaters in the semiconductor substrate;
forming a back-end-of-line (BEOL) interconnect structure on a first side of the semiconductor substrate, wherein the BEOL interconnect structure comprises a plurality of second elongated heaters, wherein from a top view the first elongated heaters extend along a first direction, the second elongated heaters extend along a second direction perpendicular to the first direction, and the sensing pixels are respectively in regions defined by the first elongated heaters and the second elongated heaters;
bonding a carrier substrate to the semiconductor substrate through the BEOL interconnect structure;
after bonding the carrier substrate to the semiconductor substrate, thinning the SOI substrate to remove the sacrificial substrate and to expose the dielectric layer;
etching the dielectric layer until a second side of the semiconductor substrate is exposed, resulting in a sensing well extending through the dielectric layer and laterally between the source/drain regions;
forming a biosensing film lining the sensing well;
immersing the biosensing film in a biological material bath until the biosensing film is coated with a biological material layer;
forming an access transistor in the semiconductor substrate, wherein the biological material layer vertically overlaps both the access transistor and the sensing pixels, and a vertical distance from the biological material layer to a channel region of the access transistor is greater than a vertical distance from the biological material layer to a channel region of one of the sensing pixels; and
forming fluid channel walls over the biological material layer, wherein one of the fluid channel walls forms a horizontal interface with the biological material layer, and an entirety of the horizontal interface vertically overlaps with one of the plurality of first elongated heaters in the semiconductor substrate.