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US 2026/0293697 A1Published application
Alignment Structure for Image Sensor
AssigneeOmniVision Technologies, Inc.
InventorsQin Wang, Yu Jin
Life of this patent
Estimating the term…
Abstract
The present disclosure provides an alignment mark structures for image sensor that involve dispose multiple sets of alignment marks on a wafer substrate for the formation of process mask layers associated with photodiodes, isolation well regions and deep trench isolation structure formation mask to improve alignment registration between process mask layers, reduce overlay shift, and improves alignment accuracy between pixel elements.
Claims20
A semiconductor device, comprising:
- a wafer having a first side and a second side opposite to the first side, the wafer including at least one active region and a peripheral region adjacent to the active region,
- a dielectric layer disposed on the first side of the wafer;
- wherein the at least one active region includes:
- a plurality of photodiodes;
- a plurality of first isolation well regions between adjacent photodiodes;
- a plurality of transfer gates on the first side, the plurality of transfer gate configured to couple the plurality of photodiodes to a plurality of floating diffusion regions;
- and
- a plurality of deep trench isolation structures extend from the second side into the wafer between adjacent photodiodes;
- wherein the peripheral region includes:
- a first set of alignment marks disposed on the first side of the wafer, configured to provide positional registration for the formation of the plurality of photodiodes;
- and
- a second set of alignment marks disposed on the first side of the wafer within a first opening of the dielectric layer, wherein the second set of alignment marks is disposed with reference to the first set of alignment marks.
9 more elements
A semiconductor device, comprising:
- a wafer having a first side and a second side opposite to the first side, the wafer including at least one die region and a peripheral region adjacent to the die region, and
- a dielectric layer on the first side of the wafer;
- wherein the at least one die region includes a pixel array region comprising:
- a plurality of photodiodes;
- a plurality of first isolation well regions between adjacent photodiodes;
- a plurality of transfer gates on the first side, the plurality of transfer gates configured to selectively couple the plurality of photodiodes to at least one floating diffusion region;
- and
- a plurality of deep trench isolation structures arranged to extend from the second side into the wafer within the die region between adjacent photodiodes;
- wherein the peripheral region includes at least one set of alignment marks;
- wherein the peripheral region is between the at least one die region and an edge of the wafer.
7 more elements
An image sensor, comprising:
- a substrate material having a first side and a second side opposite to the first side, the substrate material including at least one active region and a peripheral region adjacent to the active region,
- a dielectric layer disposed on the first side of the substrate material;
- wherein the at least one active region includes a pixel array disposed within the substrate material comprising:
- a plurality of photodiodes disposed on the substrate material;
- a plurality of isolation well regions between adjacent photodiodes;
- a plurality of floating diffusion regions disposed on the substrate material;
- a plurality of transfer gates on the first side selectively coupled the plurality of photodiodes to at least one floating diffusion regions;
- and
- a plurality of deep trench isolation structures, each of the plurality of deep trench isolation structures arranged to extend from the second side into the substrate material between adjacent photodiodes;
- wherein the peripheral region includes:
- a first set of alignment marks disposed on the first side of the substrate material, configured to provide positional registration for the formation of the plurality of photodiodes;
- and
- a second set of alignment marks disposed on the first side of the substrate material within a first opening of the dielectric layer, wherein the second set of alignment marks is disposed with reference to the first set of alignment marks.
10 more elements
Dependencies are inferred from the claim text.