Package Substrate Inspection Pads for RDL Defect Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current package technologies lack a real-time monitoring method to inspect the redistribution layer and quality of package devices, resulting in wasted resources when defects are discovered post-bonding, leading to increased manufacturing costs.
Innovation Solution
A manufacturing method involving a carrier substrate with conductive layers and a release layer, where inspection lines and pads allow for real-time electrical connectivity and signal testing to detect short-circuits or open-circuits during the redistribution layer formation, enabling immediate defect identification and potential repair.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If real-time inspection is implemented during manufacturing, then manufacturing precision and defect detection capability are improved, but device complexity increases due to additional inspection lines and pads
Solution Approach 1:
The inspection system is segmented into independent conductive layers with dedicated inspection lines and pads. The first conductive layer contains first inspection lines connecting first pads, while the second conductive layer contains second inspection lines connecting second pads. This segmentation allows independent inspection of each layer without interfering with each other, enabling real-time defect detection while maintaining manageable structural complexity.
Solution Approach 2:
The conductive layers serve dual functions: they act as both functional interconnection structures for signal transmission and as inspection pathways for defect detection. The same conductive patterns that connect functional pads also serve as inspection lines by providing continuous conductive paths from input to output pads, eliminating the need for separate dedicated inspection structures.
2Measurement precision
If inspection lines and pads are added to the conductive layers, then measurement precision for detecting short circuits and open circuits is improved, but the area occupied by the device increases
Solution Approach 1:
The conductive patterns in each layer serve dual purposes: they provide functional interconnections for signal transmission between pads and simultaneously serve as inspection lines for detecting defects. This multi-functionality eliminates the need for separate dedicated inspection structures, allowing comprehensive circuit inspection without increasing the device area.
Solution Approach 2:
The inspection functionality is merged with the functional interconnection structure. The same conductive traces that carry signals between functional pads also serve as inspection pathways. By combining these two functions into a single integrated structure, the patent achieves precise defect detection capability without requiring additional space for separate inspection lines.
3Productivity
If chips are bonded on the redistribution layer before inspection, then productivity is improved by completing bonding early, but loss of substance increases as defective devices cannot be reused after bonding
Solution Approach 1:
The inspection process is performed preliminarily, before the bonding step, by providing input signals to input pads and receiving output signals through corresponding output pads. This preliminary inspection identifies defective devices early in the manufacturing process, allowing defective substrates to be discarded before chips are bonded. Consequently, productivity is maintained while material waste is significantly reduced, as chips are only bonded to defect-free substrates.
Solution Approach 2:
The inspection system provides feedback about the quality of the redistribution layer by detecting short circuits and open circuits through the conductive paths. This feedback mechanism enables real-time quality assessment before proceeding to the bonding step, allowing the manufacturing process to adjust or discard defective substrates before committing additional resources, thereby reducing material waste while maintaining productivity.
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
Enables real-time inspection and potential repair of defects during the manufacturing process, reducing waste and costs associated with post-bonding defect discovery.
Implementation Method 1
the second conductive layer has at least one second pad that is disposed in the device region of the carrier substrate and is electrically connected to the first pad through the first conductive layer
Data Source
AI summary
The present disclosure provides a manufacturing method of a package device, which includes providing a carrier substrate, a first conductive layer, and a release layer, where the carrier substrate has a device region and a peripheral region, and the first conductive layer and the release layer are disposed on the carrier substrate. The method further includes forming a second conductive layer on the release layer in the device region, where at least one of the first and second conductive layers includes a first pad in the peripheral region. The second conductive layer includes a second pad electrically connected to the first pad through the first conductive layer. The method also includes performing an inspection step to provide an input signal to one of the first and second pads, and to receive an output signal from another of the first and second pads.