PCB Cavity Pad Structure With Steep Inner Walls
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional circuit boards face issues with increased space requirements due to the inclination angle of inner walls in cavities, leading to reduced integration density and overall volume, and the need for additional stop layers in cavity formation.
Innovation Solution
A circuit board design with controlled inclination angles of inner walls and the use of a seed layer for cavity formation, allowing for precise laser processing without additional stop layers, reducing manufacturing costs and improving integration density.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional cavity formation methods are used with drill bits or sandblasting, then cavities can be formed for embedding elements, but the inclination angle of inner walls becomes 150° or more, increasing the space required for cavity formation
Solution Approach 1:
The patent replaces mechanical cavity formation methods (drill bits, sandblasting) with laser processing. The laser processing method enables precise control of the cavity inner wall inclination angle, achieving angles closer to 90° compared to the 150° or more obtained by conventional mechanical methods. This substitution of the formation mechanism directly resolves the contradiction by providing both manufacturing precision and compact space utilization.
Solution Approach 2:
The patent changes the processing parameters by introducing laser power, scanning speed, and focal position control to achieve precise cavity formation. By optimizing these laser processing parameters, the inner wall inclination angle is controlled to be less than 150°, significantly improving upon conventional methods while reducing the required cavity space and enhancing integration density.
2Manufacturing precision
If additional stop layers are added on the bottom surface of cavities for precise depth control, then cavity depth can be accurately controlled, but the device complexity and manufacturing cost increase
Solution Approach 1:
The patent replaces the mechanical approach of adding stop layers for depth control with laser processing, where cavity depth is controlled through laser power, scanning speed, and focal position parameters. This eliminates the need for additional stop layers and their associated formation and removal processes, directly reducing device complexity while maintaining precise depth control.
Solution Approach 2:
The laser processing method inherently provides depth control through its own parameters without requiring external stop layers. The laser beam's interaction with the substrate material self-regulates the cavity formation depth based on process parameters, making the system self-sufficient and eliminating the need for additional complexity-inducing components.
3Productivity
If the cavity space is reduced to improve integration density, then more elements can be mounted, but the inclination angle requirements become more stringent and harder to achieve with conventional methods
Solution Approach 1:
The patent uses laser processing to replace mechanical cavity formation methods, enabling the creation of cavities with steep inner wall angles (close to 90°) in compact spaces. This substitution provides the manufacturing precision needed to achieve high integration density while maintaining acceptable inner wall inclination angles that would be impossible with conventional mechanical methods.
Solution Approach 2:
By changing to laser processing parameters (power, speed, focal position), the patent achieves precise control over cavity geometry even in reduced spaces. This enables high integration density while maintaining inner wall inclination angles within acceptable ranges, as the laser parameters can be optimized for each specific cavity design requirement.
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 minimizes cavity space, enhances integration density, and improves structural reliability by optimizing inner wall angles and using UV laser processing to remove glass fibers, resulting in a more compact and reliable circuit board.
Implementation Method 1
uses UV laser processing to remove glass fibers
Data Source
AI summary
A printed circuit board according to an embodiment comprises: a first insulation layer; a first circuit pattern disposed on one surface of the first insulation layer and including a pad; and a second insulation layer disposed on one surface of the first insulation layer and including a cavity exposing the pad, wherein the first circuit pattern includes a 1-1 metal layer disposed on one surface of the first insulation layer, and a 1-2 metal layer disposed on one surface of the 1-1 metal layer, wherein the area of the 1-1 metal layer is greater than the area of the 1-2 metal layer, and at least a portion of a side surface of the 1-1 metal layer is exposed through the cavity.