Semiconductor Device Bonding Recess Projection Alignment

Solution Overview

Problem

Current semiconductor devices face reliability issues due to displacement of stacked members during soldering, leading to uneven bonded layers and reduced thermal stress resistance, particularly in high-power density applications where small-size chips are prone to inclination and thermal stress vulnerabilities.

Innovation Solution

A semiconductor device design featuring a conductive plate with recesses and a bonding layer with projections that are inserted into these recesses to ensure uniform positioning and bonding, preventing displacement during soldering and maintaining a consistent bonding layer thickness, thereby enhancing reliability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If a jig with opening is used to hold stacked members during soldering, then displacement of members is prevented, but the clearance in the opening causes slight displacement and uneven solder flow

Engineering Contradiction:

Improvepositioning accuracyVSAvoidbonded layer uniformity

Core Design Contradiction:

Manufacturing precisionVSReliability

Solution Approach 1:

The patent applies preliminary action by forming projections on the bonding member before soldering and inserting them into recesses on the substrate. This pre-positioning mechanism ensures accurate alignment and prevents displacement during the soldering process, eliminating the need for jigs with clearances that cause uneven solder flow.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent replaces the mechanical jig-based positioning system with a projection-recess mechanical interlocking system. This substitution eliminates the clearance issue inherent in jig openings while maintaining precise positioning, resulting in uniform solder flow and improved bonded layer quality.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Ease of manufacture

If plate solder with no tackiness is used as bonding member, then soldering process is simplified, but displacement of stacked members occurs during heating due to shaking

Engineering Contradiction:

Improvesoldering process simplicityVSAvoidstacked member positioning stability

Core Design Contradiction:

Ease of manufactureVSStability of the object's composition

Solution Approach 1:

The patent applies preliminary action by forming projections on the bonding member before soldering and inserting them into recesses on the substrate. This pre-positioning mechanism ensures accurate alignment and prevents displacement during the soldering process, eliminating the need for jigs with clearances that cause uneven solder flow.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent replaces the mechanical jig-based positioning system with a projection-recess mechanical interlocking system. This substitution eliminates the clearance issue inherent in jig openings while maintaining precise positioning, resulting in uniform solder flow and improved bonded layer quality.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Stability of the object's composition

If clearance is provided in jig opening to avoid pressing members, then members can expand during heating, but slight displacement occurs causing inclined members

Engineering Contradiction:

Improvethermal expansion accommodationVSAvoidmember alignment precision

Core Design Contradiction:

Stability of the object's compositionVSManufacturing precision

Solution Approach 1:

The patent applies preliminary action by forming projections on the bonding member before soldering and inserting them into recesses on the substrate. This pre-positioning mechanism ensures accurate alignment and prevents displacement during the soldering process, eliminating the need for jigs with clearances that cause uneven solder flow.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent replaces the mechanical jig-based positioning system with a projection-recess mechanical interlocking system. This substitution eliminates the clearance issue inherent in jig openings while maintaining precise positioning, resulting in uniform solder flow and improved bonded layer quality.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

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 ensures a uniform bonding layer thickness, improving the reliability and environmental stability of semiconductor devices by preventing displacement and maintaining consistent contact during soldering, even under high-temperature conditions.

Implementation Method 1

heating and melting the bonding member at a temperature exceeding a melting point of the bonding member

Methodology Applied

Scientific EffectMelting: Melting

Implementation Method 2

a first solder and a second solder bonded to a rear-surface electrode by ultrasonic oscillation

Methodology Applied

Scientific EffectUltrasonic oscillation: Ultrasonic Vibration

Data Source

PatentUS20230040019A1Semiconductor device and method of manufacturing the same

Publication Date: 2023.02.09 FUJI ELECTRIC CO LTD

AI summary

A method of manufacturing a semiconductor device, the method including: preparing an insulated circuit substrate including a conductive plate; partially fixing a plate-like bonding member onto the conductive plate so as to make a positioning of the bonding member in a horizontal direction; mounting a semiconductor chip on the bonding member; and heating and melting the bonding member so as to form a bonding layer for bonding the insulated circuit substrate and the semiconductor chip each other.