Pixel Interconnect Layout for High-Resolution Image Sensors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current image sensors face challenges in achieving high resolution due to limitations in pixel isolation and interconnection structures, which affect the efficiency of light conversion and signal transmission.
Innovation Solution
The image sensor design includes a substrate with pixel isolation patterns and a conductive structure that extends parallel to the substrate surface, with contacts vertically connected to floating diffusion regions, enhancing interconnection and signal output.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If conventional interconnection structures are used, then device complexity is reduced, but integration density and cross-talk prevention are insufficient
Solution Approach 1:
The conductive structure transitions from a conventional planar interconnection layer to a three-dimensional configuration with connection portions extending parallel to the substrate surface and vertically extending contacts. This dimensional change enables higher integration density by utilizing vertical space while maintaining electrical connectivity without increasing planar footprint.
Solution Approach 2:
The conductive structure is segmented into distinct components: connection portions that extend parallel to the substrate and vertically extending contacts that connect to floating diffusion regions. This segmentation allows each component to perform its specific function optimally while preventing cross-talk between adjacent pixel regions through spatial separation.
2Reliability
If pixel isolation patterns are added to prevent cross-talk, then signal quality improves, but device complexity increases
Solution Approach 1:
The pixel isolation pattern is merged with the conductive structure design, where the isolation pattern and conductive elements work together as an integrated system. The connection portions extend between isolation patterns, and vertical contacts connect through them, creating a unified structure that prevents cross-talk while maintaining signal quality without requiring separate isolation and interconnection systems.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This design improves the resolution of the image sensor by ensuring effective light conversion and signal transmission, leading to increased integration density and reduced cross-talk between pixel regions.
Implementation Method 1
Each of the unit pixel regions includes a photodiode which is used to convert an incident light to an electric signal
Data Source
AI summary
An image sensor includes a substrate having a first surface and a second surface that are opposite to each other. The substrate including a plurality of unit pixel regions having photoelectric conversion regions and floating diffusion regions disposed adjacent to the first surface. A pixel isolation pattern is disposed in the substrate and is configured to define the plurality of unit pixel regions. An interconnection layer is disposed on the first surface of the substrate. The interconnection layer includes a conductive structure having a connection portion that extends parallel to the first surface of the substrate and is spaced apart from the first surface of the substrate. Contacts extend vertically from the connection portion towards the first surface of the substrate. Each of the contacts are spaced apart from each other with the pixel isolation pattern interposed therebetween. The contacts are coupled to the floating diffusion regions, respectively.