Power Module Terminal Slit Structure for Resin Insulation Coverage

Solution Overview

Problem

In semiconductor power modules, the insufficient application of highly-insulating voltage-resisting resin material due to assembly procedures leads to insulation failures, including air bubbles and peeling issues at the resin-substrate interface, compromising the insulation performance.

Innovation Solution

A semiconductor power module design that includes a receiving section with a slit portion in the main terminal or connected body, allowing reliable filling and application of sealing material before connection, ensuring comprehensive coverage and preventing air bubble retention.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a highly-insulating voltage-resisting resin material is applied after main terminal joining to ensure insulation performance, then insulation performance is improved, but the resin material may be introduced insufficiently due to extraction paths in metal patterns, leading to air bubbles and peeling

Engineering Contradiction:

Improveinsulation performanceVSAvoidresin material application completeness

Core Design Contradiction:

ReliabilityVSManufacturing precision

Solution Approach 1:

The patent applies the highly-insulating voltage-resisting resin material before joining the main terminal to the insulating substrate. This preliminary application ensures that the resin material fully covers the insulating substrate surface without being obstructed by the main terminal, eliminating extraction paths and preventing air bubbles and peeling while maintaining complete insulation coverage

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent inverts the conventional sequence by applying the resin material first and then joining the main terminal, rather than applying the resin after joining. This inversion resolves the contradiction by eliminating the obstruction caused by the main terminal during resin application, ensuring complete coverage and proper adhesion

Inventive Principle:

Principle #13The other way round (Inversion)

2Device complexity

If the main terminal is joined to the insulating substrate first, then the assembly structure is simplified, but the sealing resin cannot be properly applied to cover the creepage path, causing insulation failure

Engineering Contradiction:

Improveassembly structureVSAvoidinsulation performance

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The patent applies the highly-insulating voltage-resisting resin material before joining the main terminal to the insulating substrate. This preliminary application ensures that the resin material fully covers the insulating substrate surface without being obstructed by the main terminal, eliminating extraction paths and preventing air bubbles and peeling while maintaining complete insulation coverage

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent inverts the conventional sequence by applying the resin material first and then joining the main terminal, rather than applying the resin after joining. This inversion resolves the contradiction by eliminating the obstruction caused by the main terminal during resin application, ensuring complete coverage and proper adhesion

Inventive Principle:

Principle #13The other way round (Inversion)

Data Source

PatentUS11916001B2Semiconductor power module and power conversion device

Publication Date: 2024.02.27 MITSUBISHI ELECTRIC CORP

AI summary

A semiconductor power module includes a base plate, an insulating substrate, a power semiconductor element, an external terminal, a main terminal, a connected body, a case, a highly-insulating voltage-resisting resin material, a sealing resin, and a cover. The main terminal is connected to the connected body. The connected body is directly joined to the metal plate. The connected body is provided with a receiving section in which the main terminal is received. The receiving section is provided with a slit portion. The slit portion extends from a lower end side of the receiving section toward an upper end side thereof. The lower end side is located on a side close to the insulating substrate. The upper end side is located opposite to the side close to the insulating substrate.