Semiconductor Module Frame with Concave Ion Migration Protection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional semiconductor modules experience ion migration issues, leading to dendrite formation and potential short circuits when exposed to electric fields in high humidity, particularly when silver-based bonding materials are used.
Innovation Solution
A semiconductor module design featuring a metal base with an insulating frame and metal leads, where the frame's corner portions have concave structures filled with a protective thermoplastic coating material to physically press down the silver-based bonding material, preventing ion migration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a silver-based bonding material is used to fix the frame to the base, then bonding strength is improved, but ion migration occurs leading to dendrite formation and potential short circuits
Solution Approach 1:
The frame is divided into multiple regions: a flat portion for normal bonding and corner portions with concave portions for enhanced protection. This segmentation allows different functional zones within the same frame structure, enabling both strong bonding and ion migration prevention without compromising overall reliability.
Solution Approach 2:
A protective material is introduced as an intermediary substance filling the concave portions at the corner portions of the frame. This protective material acts as a barrier between the silver-based bonding material and the environment, preventing ion migration while maintaining the bonding strength provided by the silver-based material in other areas.
2Ease of manufacture
If the frame is fixed using conventional methods without concave portions, then manufacturing simplicity is maintained, but ion migration cannot be effectively prevented
Solution Approach 1:
Concave portions are pre-formed in the frame at corner portions before the bonding process. This preliminary structural preparation creates designated areas where protective material can be selectively applied, enabling ion migration prevention at critical locations without requiring complex manufacturing changes to the entire frame structure.
Solution Approach 2:
The protective material is applied locally only in the concave portions at the corner portions of the frame, rather than coating the entire frame. This local application approach prevents ion migration at the most vulnerable areas (corner portions) while maintaining manufacturing efficiency and avoiding unnecessary complexity in other regions.
3Reliability
If protective material is applied to prevent ion migration, then electrical reliability is improved, but device complexity increases
Solution Approach 1:
The protective coating is segmented and applied only to specific corner portions of the frame where concave portions are formed, rather than applying a complete coating to the entire frame. This reduces material usage and simplifies the manufacturing process while effectively preventing ion migration at the most vulnerable locations.
Solution Approach 2:
Protection is applied partially only where most needed - the corner portions of the frame are prone to ion migration and dendrite formation, so concave portions with protective material are created specifically at these locations. This partial action approach achieves sufficient protection without the complexity of comprehensive full-frame coating.
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 solution effectively curbs ion migration and dendrite growth, enhancing the reliability and longevity of semiconductor modules by ensuring a secure bond without compromising high-frequency characteristics.
Implementation Method 1
ion migration in which an ionized metal moves on a surface of a substance in the electric field occurs
Data Source
AI summary
A semiconductor module includes a base plate made of a metal, an insulating frame provided on a peripheral edge portion of the base plate, a lead made of a metal and provided on the frame, and a semiconductor device mounted on the base plate in a space surrounded by the frame, wherein the frame is fixed to the base plate by a bonding material containing silver, the frame has concave portions formed in an inner portion which is a corner portion on a space side and an outer portion which is a corner portion on a side opposite to the inner portion in a surface thereof which faces the base plate, and the concave portions are filled with a coating material.