PCB Cavity Design for Mounting Accuracy and Thickness Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing printed circuit boards face challenges in forming cavities with desired depths without damaging the circuit pattern, which affects mounting accuracy and overall product thickness.
Innovation Solution
A printed circuit board design that includes a cavity with multiple portions of varying widths and depths, allowing for precise adjustment of cavity depth without damaging the circuit pattern, and a manufacturing method that involves forming sacrificial layers and dummy patterns to achieve this design.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If the cavity depth is increased to reduce product thickness, then the overall thickness of the product packaging is reduced, but the peripheral circuit pattern may be damaged
Solution Approach 1:
The cavity is divided into multiple portions (first portion, second portion, third portion) with different widths along the height direction. This segmentation allows the cavity to achieve sufficient depth for component mounting while maintaining a wider opening that prevents damage to peripheral circuit patterns during the formation process.
Solution Approach 2:
Different portions of the cavity have different width characteristics - the upper portions have larger widths to protect circuit patterns, while the lower portion has a smaller width to provide adequate depth for component mounting. This local variation in geometry resolves the contradiction between depth and circuit protection.
2Adaptability or versatility
If the cavity depth is increased to mount more electronic components, then the mounting capacity is improved, but it becomes difficult to adjust the cavity depth without damaging the circuit pattern
Solution Approach 1:
The cavity is divided into multiple portions (first portion, second portion, third portion) with different widths along the height direction. This segmentation allows the cavity to achieve sufficient depth for component mounting while maintaining a wider opening that prevents damage to peripheral circuit patterns during the formation process.
Solution Approach 2:
The cavity geometry is designed with varying width parameters at different heights - the first and third portions have larger widths while the second portion has a smaller width. This parameter variation enables precise control over both cavity depth and circuit pattern protection during manufacturing.
3Area of stationary object
If the mounting connection portion size is reduced to minimize space, then the space utilization is improved, but it becomes difficult to accurately mount the electronic component at the board
Solution Approach 1:
The mounting connection portion utilizes the vertical dimension by extending along the height direction within the cavity. This allows the connection portion to have sufficient mounting surface area while maintaining a compact footprint in the horizontal plane, thereby improving both space utilization and mounting accuracy.
Solution Approach 2:
The mounting connection portion is nested within the cavity structure, utilizing the vertical space efficiently. This nesting approach allows for adequate connection area without increasing the overall horizontal footprint, resolving the contradiction between compactness and mounting precision.
Data Source
AI summary
A printed circuit board according to an embodiment includes: a first insulating layer; a first wiring layer buried in the first insulating layer; a first via disposed within a first via hole in the first insulating layer; a second insulating layer disposed below the first insulating layer; a second wiring layer buried in the second insulating layer; a first solder resist layer disposed on the first insulating layer; and a cavity extending along a height direction by penetrating the first solder resist layer and penetrating a portion of the first insulating layer. The cavity includes a first portion, a second portion, and a third portion having different 10 widths. Along the height direction, the first portion is disposed on the second portion and the third portion is disposed on the first portion. The first via is exposed through the second portion of the cavity.