Shield Package Surface Patterning for Readable EMI Marking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional shield packages with laser-marked sealing materials and sputtered metal thin films suffer from poor reliability in heat cycles and low productivity due to differences in thermal expansion coefficients and expensive sputtering devices, and the conductive coating material's leveling effect reduces the distinctiveness of the patterned portions.
Innovation Solution
A shield package with a surface featuring a patterned portion and a non-patterned portion, where the ratio of specific shape parameters such as Sal, Smr1, Ssk, and Rvk between the two portions is optimized to create a clear contrast in reflectance, enhancing the distinctiveness of the patterned design, which can include lines, dots, or two-dimensional codes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If a metal thin film is deposited on the sealing material by sputtering to form a shield layer, then a patterned portion with irregularities is formed that shows high distinctiveness, but the reliability in heat cycle test deteriorates due to different coefficient of linear expansion between the sealing material and the metal thin film
Solution Approach 1:
The patent replaces the expensive sputtering process with a spray coating method using conductive paint. This disposable, simpler coating method achieves the shielding function without the reliability issues of sputtered metal films during heat cycling, effectively substituting a complex, problematic process with a simpler, more reliable alternative.
Solution Approach 2:
The patent changes the formation method of the shield layer from physical vapor deposition (sputtering) to liquid spray coating. This parameter change in the deposition process eliminates the thermal expansion mismatch problem while maintaining the patterned portion's distinctiveness through controlled spray application on the laser-etched surface.
2Productivity
If a conductive coating material is applied to the surface of the sealing material by spraying to form a shield layer, then productivity is improved and cost is reduced, but the boundary of the patterned portion becomes unclear due to the leveling effect that smooths the shield layer
Solution Approach 1:
The patent applies preliminary laser etching to create grooves and fine irregularities on the sealing material surface before applying the conductive coating. This preliminary action ensures that when the spray coating is applied, the underlying surface irregularities remain visible through the conductive layer, maintaining patterned portion distinctiveness while allowing the use of the productive spray method.
Solution Approach 2:
The patent creates local variations in the shield layer by spraying conductive coating material over the laser-etched surface. The conductive paint accumulates differently in the grooves versus the raised areas, creating local quality differences that preserve the patterned portion boundaries while using the efficient spray application method throughout.
3Adaptability or versatility
If the mounting density of electronic components is increased to provide smaller and lighter devices with higher functionality, then the functionality and integration are improved, but the noise generation and noise sensitivity increase
Solution Approach 1:
The patent segments the package surface into distinct patterned and non-patterned portions through laser etching and selective coating. This segmentation creates clear visual boundaries that help identify and isolate noise-sensitive areas, allowing for better noise management in high-density mounting configurations where components are closely packed.
Solution Approach 2:
The patent uses the conductive coating material to create visual contrast between patterned and non-patterned portions, effectively using 'color' or reflectance changes to distinguish different functional areas. This visual differentiation helps in identifying noise-sensitive regions and implementing appropriate shielding or filtering measures in high-density electronic assemblies.
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 optimized shield package achieves improved distinctiveness and readability of the patterned portions, reducing reflection and enhancing the visibility of the design, while maintaining sufficient shielding performance and cost-effectiveness.
Implementation Method 1
a laser beam is applied to a sealing material of a package to etch a surface of the sealing material, whereby a groove is formed
Implementation Method 2
when a conductive coating material is applied to the surface of the sealing material by spraying
Data Source
AI summary
The present invention aims to provide a shield package having a highly distinctive patterned portion formed on a surface of a shield layer. The shield package of the present invention includes a package in which an electronic component is sealed with a sealing material, and a shield layer covering the package, wherein a surface of the shield layer includes a patterned portion and a non-patterned portion other than the patterned portion, and a ratio of Sal (autocorrelation length) of the non-patterned portion to Sal of the patterned portion is as follows: (Sal of non-patterned portion)/(Sal of patterned portion)>4.0.