Multi-layered Wiring Substrate Simultaneous Curing

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

The existing methods for manufacturing wiring substrates using an inkjet method often result in stress at the interfaces between layers, leading to cracks when external impact or heat is applied, due to the hardening contraction of insulating patterns formed individually.

Innovation Solution

A multi-layered structure forming method that involves forming a first insulating material layer, semi-hardening it, followed by a conductive material layer, and then a second insulating material layer, with all layers being simultaneously heated to prevent stress buildup between the layers.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If insulating patterns are formed individually using inkjet method, then the outline of via hole is clearer and insulating layer can be formed widely, but stress remains in the interface between individually formed insulating patterns due to hardening contraction, leading to cracks when external impact or heat is applied

Engineering Contradiction:

Improveoutline clarityVSAvoidinterface strength

Core Design Contradiction:

Manufacturing precisionVSReliability

Solution Approach 1:

The patent combines multiple insulating patterns into a single integrated insulating layer that is formed and hardened simultaneously. This merging approach eliminates the interfaces between individually formed patterns, thereby removing the stress concentration points that would lead to cracks under external impact or heat.

Inventive Principle:

Principle #5Merging (Combining)

2Ease of manufacture

If multiple resin layers are stacked using inkjet method, then cost is reduced compared to thin film coating and photolithography, but stress remains in the interface between base layer and covering layer, leading to cracks when external impact or heat is applied

Engineering Contradiction:

Improvemanufacturing costVSAvoidinterface strength

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The patent merges multiple resin layers into a single integrated structure that is formed and hardened simultaneously using inkjet method. This eliminates the interfaces between stacked layers, preventing stress accumulation while maintaining the cost advantages of inkjet manufacturing.

Inventive Principle:

Principle #5Merging (Combining)

3Manufacturing precision

If insulating material layers are hardened sequentially, then each layer can be formed with precise control, but stress builds up at interfaces due to hardening contraction, reducing structural stability

Engineering Contradiction:

Improvelayer formation controlVSAvoidstructural stability

Core Design Contradiction:

Manufacturing precisionVSStability of the object's composition

Solution Approach 1:

The patent applies preliminary support structures during the simultaneous hardening process to compensate for the contraction forces that occur when the insulating material layers are hardened together. This preliminary action prevents stress buildup at interfaces while maintaining the precision of layer formation.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent modifies the hardening parameters by using simultaneous hardening instead of sequential hardening. This parameter change eliminates the progressive stress accumulation that occurs with sequential processing, thereby improving structural stability while maintaining manufacturing precision through controlled simultaneous curing.

Inventive Principle:

Principle #35Parameter changes

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

This method ensures structural stability of the multi-layered structure by eliminating stress at the interfaces, making it resistant to external impact and heat.

Implementation Method 1

simultaneously heating the first insulating material layer, the conductive material layer, and the second insulating material layer

Methodology Applied

Scientific EffectThermal heating: Heating

Implementation Method 2

semi-hardening the first insulating material layer by radiating light having a first wavelength to the first insulating material layer

Methodology Applied

Scientific EffectPhoto-curing: Photopolymerisation

Data Source

PatentUS7723243B2Multi-layered structure forming method, method of manufacturing wiring substrate, and method of manufacturing electronic apparatus

Publication Date: 2010.05.25 SEIKO EPSON CORP

AI summary

There is provided a multi-layered structure forming method comprising: (A) forming a first insulating material layer containing a first photo-curing material on a substrate; (B) semi-hardening the first insulating material layer by radiating light having a first wavelength to the first insulating material layer; (C) forming a conductive material layer on the semi-hardened first insulating material layer by ejecting droplets of a conductive material to the semi-hardened first insulating material layer from a nozzle of a liquid droplet ejecting apparatus; (D) forming a second insulating material layer containing a second photo-curing material so as to cover the semi-hardened first insulating material layer and the conductive material layer; and (E) forming a first insulating layer, a conductive layer positioned on the first insulating material, and a second insulating layer covering the first insulating layer and the conductive layer by simultaneously heating the first insulating material layer, the conductive material layer, and the second insulating material layer.