Multilayer Capacitor Glass Layer Design for Moisture Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Multilayer ceramic capacitors face challenges in maintaining moisture resistance while minimizing size and maximizing capacitance, as thick cover layers increase component size and reduce capacitance.
Innovation Solution
A multilayer capacitor design featuring a stack structure with dielectric layers and internal electrodes, where the external electrodes include a glass layer with a discontinuous inner region and a thicker outer region to prevent moisture and plating solution intrusion, and the electrode layers are made of materials like Cu and Ni, with the glass layer having the same components as the body to enhance protection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a thick cover layer is formed to improve moisture resistance, then moisture resistance is improved, but component size increases and capacitance decreases
Solution Approach 1:
The glass layer is designed with non-uniform thickness, being thicker at the outer region (exposed to environment) and thinner at the inner region (near the body). This local variation optimizes moisture protection where needed while minimizing size impact. The discontinuous region further refines this by concentrating glass material at critical exposure points rather than uniformly throughout.
Solution Approach 2:
The glass layer is segmented into distinct regions: an inner region adjacent to the body, an outer region exposed to the environment, and a discontinuous region connecting them. This segmentation allows each region to serve its specific function - the outer region provides primary moisture barrier protection, while the inner region maintains structural integrity with minimal thickness to preserve capacitance.
2Reliability
If a thick cover layer is formed to prevent moisture penetration, then moisture resistance is improved, but capacitance decreases with the same size
Solution Approach 1:
The glass layer thickness is locally optimized - thicker at the outer region where moisture protection is most critical, and thinner at the inner region where excessive thickness would unnecessarily reduce capacitance. This localized approach maximizes protection while preserving electrical performance.
Solution Approach 2:
Instead of forming a uniformly thick glass layer throughout, the invention applies glass material partially - concentrated at the outer region and discontinuous regions where moisture protection is needed, while minimizing or eliminating it in the inner region where it would only harm capacitance without providing additional protection.
3Volume of moving object
If the glass layer is made thin to reduce component size, then component size is reduced, but moisture resistance deteriorates
Solution Approach 1:
The glass layer is made thin overall to reduce component size, but locally thickened at the outer region where moisture exposure occurs. This creates a thickness gradient that provides adequate protection at critical points while maintaining small overall dimensions.
Solution Approach 2:
The glass layer is segmented into thickness zones - a thinner inner region that minimizes size and a thicker outer region that ensures moisture resistance. The discontinuous region bridges these zones, providing protection only where geometrically necessary based on environmental exposure.
Data Source
AI summary
A multilayer capacitor includes a body including a stack structure in which dielectric layers are stacked and internal electrodes are stacked with one of the dielectric layers interposed therebetween and first and second external electrodes disposed on the body and connected to the first and second internal electrodes, respectively. The first external electrode includes a first electrode layer covering a first surface of the body to which the first internal electrode is exposed, a glass layer covering the first electrode layer and a second surface of the body connected to the first surface, and a second electrode layer covering the glass layer, and the glass layer includes an inner region having a discontinuous region and an outer region covering the second surface of the body and having an end exposed from the second electrode layer.