Circuit Board Groove Layout for Precise Close-Spaced Conductors

Solution Overview

Problem

Existing circuit board technologies face limitations in achieving high accuracy in forming multiple conductor patterns due to the proximity of these patterns, which is challenging with photolithography.

Innovation Solution

The circuit board design includes a substrate body with insulator layers and conductor layers where the conductor layers are aligned orthogonally, featuring a groove structure and laser beam irradiation to separate closely positioned conductors, enhancing accuracy and reducing capacitance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If photolithography is used to form multiple conductor patterns, then the manufacturing process is simple and efficient, but the positioning accuracy deteriorates when conductors are closely spaced

Engineering Contradiction:

Improvepositioning accuracy of conductor patternsVSAvoidcomplexity of formation process

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

The formation process is segmented into two distinct stages: first, conductor patterns are formed using photolithography; second, grooves are formed using laser beam irradiation to separate closely spaced conductors. This segmentation allows each process to optimize for its specific function, achieving high positioning accuracy without excessive overall complexity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Grooves are introduced as an intermediary structure between closely spaced conductor patterns. These grooves act as physical separators that improve positioning accuracy and reduce capacitance, while being formed through a separate laser processing step that does not interfere with the initial photolithography process.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Productivity

If conductor patterns are placed close to each other to increase circuit density, then the productivity and integration are improved, but the positioning accuracy and signal interference control deteriorate

Engineering Contradiction:

Improvecircuit density and integrationVSAvoidpositioning accuracy of conductor patterns

Core Design Contradiction:

ProductivityVSManufacturing precision

Solution Approach 1:

Grooves are introduced as an intermediary structure between closely spaced conductor patterns. These grooves act as physical separators that improve positioning accuracy and reduce capacitance, while being formed through a separate laser processing step that does not interfere with the initial photolithography process.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The solution moves from a two-dimensional planar arrangement of conductors to a three-dimensional structure by adding vertical grooves. This dimensional change allows conductors to be placed closer horizontally while maintaining positioning accuracy through the vertical separation provided by the grooves.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

3Manufacturing precision

If conventional photolithography is used for conductor formation, then the manufacturing process is straightforward, but the formation time increases for high-precision requirements

Engineering Contradiction:

Improveaccuracy of conductor pattern formationVSAvoidconductor pattern formation time

Core Design Contradiction:

Manufacturing precisionVSLoss of time

Solution Approach 1:

The formation process is segmented into two distinct stages: first, conductor patterns are formed using photolithography; second, grooves are formed using laser beam irradiation to separate closely spaced conductors. This segmentation allows each process to optimize for its specific function, achieving high positioning accuracy without excessive overall complexity.

Inventive Principle:

Principle #1Segmentation

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 design allows for high-accuracy positioning of closely spaced conductors, reduces formation time, prevents strength loss in insulator layers, and minimizes capacitance between conductors.

Implementation Method 1

after the pattern forming step, linearly irradiating the conductor layer with a laser beam when viewed in the up-down direction to separate the conductor layer into a first conductor layer and a second conductor layer

Methodology Applied

Scientific EffectLaser beam irradiation: Laser

Data Source

PatentUS12418977B2Circuit board and method of manufacturing circuit board

Publication Date: 2025.09.16 MURATA MFG CO LTD

AI summary

A circuit board includes one or more insulator layers, and upper and lower principal surfaces, and conductor layers in or on the substrate body. The conductor layers include a pair of first and second conductor layers on one of the insulator layers. Each of the pairs of the first and second conductor layers includes a first proximity section in which the first and second conductor layers are aligned in an orthogonal direction to an extending direction of the first conductor layer. A distance between the first and second conductor layers in the first proximity section is defined as a proximity distance. Most proximate first and second conductor layers are defined as the first and second conductor layers with a smallest proximity distance and are located on an upper principal surface of a first insulator layer of the one or more insulating layers.