Multilayer Substrate Notch Clamping for Blind-Hole-Free Power Modules
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing transfer molding processes for power modules result in blind holes due to the use of retract pins, leading to insufficient thickness in packaging layers and potential leakage or damage, compromising the integrity of the modules.
Innovation Solution
A multilayer substrate design featuring metal layers with notches that engage clamping tools, allowing secure clamping without retract pins, and a molding process that forms circular holes for screw mounting, ensuring stable encapsulation and preventing displacement during resin injection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If retract pins are used to secure the multilayer substrate during transfer molding, then the substrate displacement is prevented, but blind holes are created in the molded module
Solution Approach 1:
The invention removes the retract pin from the molding process entirely. Instead, positioning holes are pre-formed in the multilayer substrate before molding, allowing positioning rods to engage these holes and secure the substrate without creating blind holes in the final module structure.
Solution Approach 2:
The positioning holes are created in the multilayer substrate before the molding process begins. This preliminary action allows the positioning rods to be inserted and secured in advance, preventing the need for retract pins that would create blind holes during or after molding.
2Stability of the object's composition
If retract pins are used to secure the multilayer substrate, then substrate displacement is prevented, but the packaging layer thickness around blind holes becomes insufficient
Solution Approach 1:
The invention extracts the problematic retract pin mechanism from the process. By using pre-formed positioning holes in the substrate that engage with positioning rods, the packaging layer can uniformly surround the rods without the thinning effect caused by blind hole formation, ensuring sufficient thickness for leakage prevention.
3Ease of manufacture
If traditional transfer molding with retract pins is used, then the molding process can be completed, but leakage or abnormal discharge may occur
Solution Approach 1:
The invention removes the retract pin that causes blind holes and subsequent leakage risks. The positioning holes in the substrate provide a sealed pathway for positioning rods, eliminating the packaging layer thinning and potential leakage channels created by blind holes.
Solution Approach 2:
Positioning holes are pre-formed in the substrate with appropriate dimensions and locations. This preliminary preparation ensures that when positioning rods are inserted, they are properly secured without creating blind holes, thereby preventing leakage from the outset.
4Stability of the object's composition
If notches are added to metal layers for clamping tool engagement, then clamping stability is improved, but manufacturing complexity increases
Solution Approach 1:
The notches are pre-formed in the metal layers during substrate fabrication, before the molding process. This preliminary action allows clamping tools to engage these notches and secure the substrate during molding, providing stability without requiring complex additional components or processes.
Data Source
AI summary
The present disclosure relates to multilayer substrates and methods of manufacturing the same, power modules and methods of manufacturing the same, and electrical systems. The multilayer substrate may comprise an insulating material layer and first and second metal layers attached to the insulating material layer on respective opposite surfaces. The second metal layer comprises: a first portion overlapping the insulating material layer and used for attaching one or more chips thereon; and a second portion extending outwards from the first portion and extending beyond the insulating material layer at least on opposite first and second sides of the second metal layer. The second portion has at least one pair of first notches extending inwards from edges, and each pair of first notches are located at corresponding positions on the first and second sides of the second metal layer, respectively.