Semiconductor Package Test Line Structure for Early Die Screening
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Testing of semiconductor packages is typically performed after all components are integrated, leading to significant losses when defects are detected, as the entire package, including an expensive external substrate, is discarded.
Innovation Solution
Incorporation of a first test line structure between the interposer and die device structure, allowing early detection of defects in individual dies or interposer components before integration with an external substrate, using conductive bumps to electrically couple test lines for probing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If testing is performed after complete package fabrication and integration, then comprehensive functional verification is achieved, but significant loss occurs when defects are detected requiring discard of entire package including external substrate
Solution Approach 1:
The patent implements preliminary testing actions by incorporating test line structures and test access mechanisms before final package completion. Test lines are embedded in the substrate during fabrication, allowing defect detection to occur at intermediate stages rather than after full integration, thereby preventing waste of completed package components
Solution Approach 2:
The testing function is segmented from the main package structure through separate test line structures and access mechanisms. This segmentation allows independent testing of substrate and component interconnections without requiring the entire package to be finalized, enabling early defect detection while maintaining comprehensive verification capability
2Reliability
If testing is performed after integration with external substrate, then complete package functionality is verified, but cost increases due to discard of expensive external substrate and components
Solution Approach 1:
The patent performs preliminary functionality verification through embedded test lines that can assess substrate and interconnection integrity before expensive external substrate integration. This preliminary action identifies defects early, preventing wasteful expenditure on subsequent processing of defective packages
Solution Approach 2:
Test line structures serve as intermediary elements between package components and testing equipment. These intermediaries enable functional verification at intermediate stages without requiring final package assembly, allowing cost-effective detection of defects before expensive materials are committed
3Loss of time
If test line structure is incorporated between interposer and die device structure, then early defect detection is enabled, but device complexity increases
Solution Approach 1:
The test line structures are merged with the substrate fabrication process rather than being added as separate post-processing components. Test lines are formed using the same lithography and deposition steps as signal lines, integrating testing capability into the existing manufacturing flow without significant structural complexity addition
Solution Approach 2:
The test line structures serve multiple functions: they provide both signal routing for normal operation and testing pathways for defect detection. This multi-functionality reduces the need for separate dedicated test structures, minimizing the increase in device complexity while enabling early defect detection
Data Source
AI summary
A package comprises an interposer, comprising an interposer substrate including at least one layer, and a plurality of RDLs formed through at least a portion of the interposer substrate. The package also includes a die device structure comprising at least one device die, and a first test line (TL) structure interposed between the interposer and the die device structure. The first TL structure includes at least one first test line electrically coupled to the at least one device die, at least a portion of the at least one first test line extending beyond a peripheral edge of the die device structure to provide an electrical interface with the at least one device die.