Pixel Shield Layout for Noise-Resistant Imaging Circuits
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing imaging devices suffer from noise interference due to the proximity of voltage lines and wiring lines, which affects the signal quality and accuracy of photoelectric conversion.
Innovation Solution
The implementation of a first shield in the imaging device with a closer distance to the voltage line than to the wiring line, effectively suppressing noise from entering the wiring line.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If voltage lines are placed close to wiring lines for compact design, then device integration is improved, but noise interference increases
Solution Approach 1:
A shield line is introduced as an intermediary element between the voltage line and the wiring line (signal line). The shield line acts as a mediator that blocks electromagnetic noise from the voltage line from interfering with the signal line, while allowing the voltage line to remain in close proximity for compact design. The shield line is connected to ground potential to effectively dissipate interfering electromagnetic signals.
2Object-affected harmful factors
If shield is placed closer to voltage line than to wiring line, then noise suppression is improved, but wiring line protection may be reduced
Solution Approach 1:
The shield line is positioned asymmetrically with different distances to the voltage line and wiring line. Specifically, the shield line is placed closer to the voltage line than to the wiring line. This local variation in positioning optimizes noise suppression from the voltage line while maintaining adequate protection for the wiring line through the shield's electromagnetic blocking effect.
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 significantly reduces noise interference, enhancing the signal quality and accuracy of photoelectric conversion processes.
Implementation Method 1
a first shield, wherein... a distance between the first voltage line and the first shield is smaller than a distance between the first voltage line and the first wiring line
Implementation Method 2
a first pixel that performs photoelectric conversion... a first wiring line being a wiring line through which a first signal charge obtained by photoelectric conversion performed by the first pixel flows
Data Source
AI summary
An imaging device includes a semiconductor substrate, a first pixel that performs photoelectric conversion, and a first shield. The first pixel includes a first diffusion region that is present in the semiconductor substrate, a first wiring line connected to the first diffusion region, a first transistor, and a first voltage line that makes up at least part of a voltage supply path to a drain or a source of the first transistor. A first signal charge obtained by photoelectric conversion performed by the first pixel flows through the first wiring line. The first signal charge flows into a gate of the first transistor via the first wiring line. Voltages that are different from each other are applied to the first voltage line. A distance between the first voltage line and the first shield is smaller than a distance between the first voltage line and the first wiring line.