Ceramic Laminated Substrate Layout for Uniform Solder Bonding

Solution Overview

Problem

In electronic devices with both pillar and stripe bumps, irregular solder heights can lead to mounting defects such as conduction and tilt defects due to uneven metal deposition during plating, causing issues with bonding between solders and land electrodes.

Innovation Solution

A ceramic laminated substrate with a laminate structure featuring via conductors, terminal electrodes, and land electrodes of varying sizes, where the first land electrode has a bump electrode with a higher plating layer and the second land electrode has a membrane electrode with a bonding surface to ceramic layers, ensuring consistent bonding heights and reducing mounting defects.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If both pillar bumps and stripe bumps are formed on the electronic device, then heat dissipation is improved, but solder height irregularity occurs due to uneven metal deposition during plating

Engineering Contradiction:

Improveheat dissipationVSAvoidsolder height uniformity

Core Design Contradiction:

TemperatureVSManufacturing precision

Solution Approach 1:

The patent applies local quality by forming a convex portion specifically at the center of the large-area land electrode where metal deposition is excessive. This localized structural modification compensates for the uneven plating distribution, ensuring that the convex portion reduces the effective height in the excessive deposition area, thereby achieving uniform solder heights across both small and large area electrodes while maintaining the heat dissipation function of the stripe bumps

Inventive Principle:

Principle #3Local quality

2Reliability

If metal plating is performed on land electrodes of varying sizes, then electrical connectivity is established, but uneven metal deposition causes pillar bumps to become lower than stripe bumps

Engineering Contradiction:

Improveelectrical connectivityVSAvoidbump height uniformity

Core Design Contradiction:

ReliabilityVSManufacturing precision

Solution Approach 1:

The patent applies local quality by forming a convex portion specifically at the center of the large-area land electrode where metal deposition is excessive. This localized structural modification compensates for the uneven plating distribution, ensuring that the convex portion reduces the effective height in the excessive deposition area, thereby achieving uniform solder heights across both small and large area electrodes while maintaining the heat dissipation function of the stripe bumps

Inventive Principle:

Principle #3Local quality

3Ease of manufacture

If solders of different heights are formed on pillar and stripe bumps, then mounting is possible, but conduction defects occur due to improper bonding to land electrodes

Engineering Contradiction:

Improvemounting capabilityVSAvoidbonding quality

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The patent applies local quality by forming a convex portion specifically at the center of the large-area land electrode where metal deposition is excessive. This localized structural modification compensates for the uneven plating distribution, ensuring that the convex portion reduces the effective height in the excessive deposition area, thereby achieving uniform solder heights across both small and large area electrodes while maintaining the heat dissipation function of the stripe bumps

Inventive Principle:

Principle #3Local quality

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 suppresses mounting defects by ensuring proper bonding of solders to land electrodes, enhancing the reliability of electronic component mounting on ceramic laminated substrates.

Implementation Method 1

a plating layer formed on a surface of the bump electrode... and a plating layer formed on a surface of the membrane electrode

Methodology Applied

Scientific EffectElectroplating: Electroplating

Data Source

PatentUS12183666B2Ceramic laminated substrate, module, and method of manufacturing ceramic laminated substrate

Publication Date: 2024.12.31 MURATA MFG CO LTD

AI summary

Provided is a ceramic laminated substrate which is formed on an electronic component to be mounted and is less likely to cause mounting defects even if there is irregularity in the height of solders. The ceramic laminated substrate includes: a ceramic laminate on which ceramic layers are laminated; via conductors; terminal electrodes; and a land electrode. The land electrode has a first land electrode and a second land electrode that are used to join different terminal electrodes of a single electronic component. The area of the first land electrode is smaller than the area of the second land electrode, and the first land electrode has a bump electrode and a plating layer, the second land electrode has a membrane electrode and plating layers, and the height of the first land electrode is formed higher than the height of the second land electrode.