Image Sensor Multi-Layer Shielding Structure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current optical black pixel arrays in image sensors face challenges in achieving effective light shielding and electrical insulation, leading to noise interference and incomplete dark state compensation.
Innovation Solution
The implementation of a multi-layered shielding structure comprising first and second planar shielding layers and a third ring-shaped shielding layer, surrounding the photoelectric transformation element, along with a signal transmission unit and supporting units, enhances light shielding and electrical insulation properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a single shielding layer is used in the optical black pixel array, then the device complexity is reduced, but the light shielding property and electrical insulating property are insufficient
Solution Approach 1:
The shielding structure is divided into multiple independent shielding layers (first shielding layer, second shielding layer, third shielding layer) with different orientations and functions. Each layer provides specific shielding capability, and together they form a comprehensive shielding system that achieves superior light blocking and electrical insulation without requiring a single complex layer
Solution Approach 2:
The shielding layers are arranged in a nested configuration where the first shielding layer is formed on the front surface, the second shielding layer on the back surface, and the third shielding layer penetrates through the substrate to connect both surfaces. This nested arrangement creates overlapping shielding zones that enhance both light shielding and electrical insulation properties
2Reliability
If multiple shielding layers are added to improve light shielding, then the light shielding property improves, but the manufacturing process becomes more complex
Solution Approach 1:
The first shielding layer is formed on the front surface before substrate thinning, and the second shielding layer is formed on the back surface after thinning. This preliminary and sequential formation approach allows each shielding layer to be optimized independently while maintaining compatibility with the overall manufacturing process
Solution Approach 2:
The shielding structure extends into the third dimension by having the third shielding layer penetrate vertically through the substrate to connect the first and second shielding layers. This vertical dimension adds comprehensive electrical insulation and light shielding without significantly increasing lateral complexity
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 configuration effectively shields incident light and electrical crosstalk, enabling the generation of optical black signals with a dark level without noise, improving the overall performance of the image sensor.
Implementation Method 1
Each of the first to second shielding layers is formed of an insulation material including a light shielding property
Implementation Method 2
The first and second shielding layers overlapped to photoelectric transformation element and formed over the first and second surfaces, respectively
Data Source
AI summary
This technology relates to an image sensor. The image sensor includes a substrate including a photoelectric transformation element, the substrate includes a first surface and a second surface faced to the first surface; first and second shielding layers overlapped to photoelectric transformation element and formed over the first and second surfaces, respectively; and a third shielding layer surrounding the photoelectric transformation element and contacted to the first and second shielding layers by penetrating the substrate.