Interposer Test Contacts for Damage-Free Known Good Die Probing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Known good die (KGD) testing operations in semiconductor manufacturing often damage connection structures on interposers, leading to air pockets and discontinuities that decrease the reliability of solder joints between the interposer and substrate, affecting the quality and yield of high-performance computing (HPC) semiconductor packages.
Innovation Solution
Incorporating a set of test contact structures on the top surface of the interposer that are electrically connected to the IC die through traces, allowing for testing without probing the connection structures, thereby avoiding damage and improving the reliability of solder joints.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If KGD testing operations probe the connection structures to test IC die quality, then testing can be performed, but damage to connection structures occurs causing air pockets and discontinuities that decrease solder joint reliability
Solution Approach 1:
The patent separates the testing function from the connection structures by creating dedicated test contact structures on the interposer. This segmentation allows testing to occur on separate contact points rather than through the actual connection structures, preventing damage while maintaining testing capability.
Solution Approach 2:
The test contact structures serve as an intermediary element between the testing equipment and the IC die. These intermediate contacts allow probe needles to access test signals without directly contacting or damaging the connection structures that form solder joints.
2Productivity
If probe needles contact connection structures during testing, then IC die can be tested, but air pockets and discontinuities are created in solder joints
Solution Approach 1:
The interposer is segmented to include both connection structures for solder joints and separate test contact structures for probing. This segmentation enables independent functionality where testing occurs on dedicated contacts rather than on the connection structures themselves, preserving solder joint integrity.
Solution Approach 2:
The test contact structures replicate the electrical connection function without serving the mechanical solder joint function. These copied contact points allow testing signals to pass through the interposer without compromising the actual connection structures that form reliable solder joints.
3Loss of information
If connection structures are damaged during testing, then testing information can be obtained, but yield and quality of semiconductor packages decrease
Solution Approach 1:
Test contact structures act as intermediary elements that transfer testing signals from probe needles to the IC die through the interposer. This intermediary system enables complete testing data acquisition while physically protecting the connection structures from damage, thereby maintaining high package yield.
Solution Approach 2:
The test contact structures serve as disposable or sacrificial elements that absorb the mechanical stress and potential damage from probing operations. By concentrating wear and potential damage on these dedicated test contacts rather than on the valuable connection structures, overall package yield is preserved.
Data Source
AI summary
A semiconductor package, which may correspond to a high-performance computing package, includes an integrated circuit die electrically and/or mechanically connected to a top surface of an interposer and a plurality of connection structures electrically and/or mechanically connected to a bottom surface of the interposer. The top surface of the interposer includes a set of test contact structures (e.g., one or more test bumps) that are electrically connected to the integrated circuit die through traces of the interposer. The set of test structures may be contacted by a probe needle to test a quality and/or a reliability of the integrated circuit die, as well as verify that traces of the interposer are functional. The set of test contact structures allows the integrated circuit die and traces of the interposer to be tested without probing the connection structures.