Inductor Shielding Structure for Substrate Eddy Current Suppression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
As integrated circuit components shrink, the eddy currents generated by substrates during inductor operation negatively affect the quality factor value (Q value) of inductors, necessitating an effective shielding solution.
Innovation Solution
A shielding structure comprising a patterned shielding layer extended between the inductor and substrate, coupled with a ring structure stacked perpendicular to the plane, which surrounds the patterned shielding layer and includes openings and a ground terminal to enhance shielding efficacy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If the inductor size is reduced to meet integrated circuit miniaturization, then the device size decreases, but the eddy current effect from the substrate increases and degrades the quality factor
Solution Approach 1:
A shielding structure is introduced as an intermediary element between the inductor and substrate. This shielding structure includes a patterned shielding layer and a ring structure that together form a protective barrier, preventing the harmful eddy currents generated by the substrate from affecting the inductor's quality factor while allowing the inductor to maintain its miniaturized size
Solution Approach 2:
The shielding structure is divided into two segmented components: a patterned shielding layer with specific geometric patterns and a ring structure surrounding the inductor. This segmentation allows each component to perform specific shielding functions, with the patterned layer providing primary eddy current blocking and the ring structure providing additional shielding and grounding paths
2Object-affected harmful factors
If a shielding structure is added to reduce eddy current effects, then the quality factor is improved, but the device complexity increases
Solution Approach 1:
The shielding structure is merged with the existing inductor fabrication process and substrate structure. The patterned shielding layer is formed using standard photolithography and deposition techniques that are already part of the CMOS manufacturing process, and the ring structure is integrated into the substrate layout, thereby reducing the added complexity
Solution Approach 2:
The shielding structure serves multiple functions simultaneously: it blocks eddy currents from the substrate, provides electrostatic discharge protection, offers electromagnetic interference shielding, and can be integrated with existing grounding schemes. This multi-functionality justifies the added structural elements by providing multiple benefits from a single integrated solution
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
The combination of the patterned shielding layer and ring structure effectively reduces mutual inductance and maintains or improves the quality factor value of the inductor, while grounding through the ring structure facilitates faster grounding, thereby enhancing the shielding effect.
Implementation Method 1
the eddy current generated by the substrate will affect the quality factor value (Q value) of the inductor
Implementation Method 2
the eddy current generated by the substrate will affect the quality factor value (Q value) of the inductor
Data Source
AI summary
A shielding structure is disclosed. The shielding structure includes a patterned shielding layer and a ring structure. The patterned shielding layer is extended along a plane and located between an inductor structure and a substrate. The ring structure is coupled to and stacked on the patterned shielding layer along a first direction. The first direction is perpendicular to the plane. The ring structure surrounds the patterned shielding layer. The ring structure includes at least one opening and a ground terminal.