Deep trench isolation structure for image sensor
AssigneeMagvision Semiconductor (Beijing) Inc.
InventorsGang Chen, Chin Poh Pang
Life of this patent
Estimating the term…
Abstract
An image sensor device is disclosed. The image sensor device includes a substrate having a plurality of pixel regions. Two adjacent pixel regions are optically isolated by an isolation structure. In an embodiment, a method of forming the isolation structure includes receiving a workpiece having a first substrate, etching a frontside of the first substrate to form a first trench, depositing a fill layer in the first trench, removing a portion of the fill layer from the backside of the first substrate to form a second trench surrounded by the fill layer, and depositing a metal layer in the second trench to form the isolation structure.
Claims20
A method of forming an image sensor, comprising:
- receiving a workpiece having a first substrate;
- etching a frontside of the first substrate, thereby forming a first trench;
- depositing a fill layer in the first trench;
- removing a portion of the fill layer from a backside of the first substrate, thereby forming a second trench surrounded by the fill layer;
- and
- depositing a metal layer in the second trench, thereby forming an isolation structure comprising the metal layer and the fill layer, wherein the isolation structure separates adjacent pixel regions of the image sensor.
A method of forming an image sensor, comprising:
- receiving a substrate comprising an isolation structure formed in a frontside of the substrate;
- forming a first trench extending through the isolation structure and into a portion of the substrate;
- filling the first trench with a first conductive material;
- removing a bottom portion of the substrate, thereby exposing the first conductive material from a backside of the substrate;
- removing a center portion of the first conductive material from the backside of the substrate, thereby forming a second trench;
- filling the second trench with a second conductive material;
- and
- removing a portion of the second conductive material from the backside of the substrate.
A method of forming an image sensor, comprising:
- receiving a substrate;
- forming a first trench extending into a top portion of the substrate;
- filling the first trench with a first conductive material;
- forming a photodiode in a region of the substrate adjacent the first trench;
- after the forming of the photodiode, thinning a bottom portion of the substrate, thereby exposing a bottom portion of the first conductive material;
- partially recessing the bottom portion of the first conductive material to form a second trench;
- filling the second trench with a second conductive material;
- and
- forming a color filter overlying the photodiode.
Dependencies are inferred from the claim text.