Acoustic Crack Detection in Semiconductor Substrates During Loading
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The fabrication of semiconductor devices can cause mechanical stress leading to cracks or plastic deformations in the semiconductor substrate, which impairs the electrical functionality of the devices. Existing methods lack a fast and cost-efficient way to detect such damage.
Innovation Solution
A system comprising a force generating unit, a detector unit with a resonating indenter and an acoustic emission sensor, and an evaluation unit to detect acoustic signals and determine if a crack or irreversible deformation has occurred in the semiconductor substrate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If pressure is applied to the semiconductor substrate during fabrication, then electrical functionality testing or wire bonding can be performed, but cracks or plastic deformations may occur in the semiconductor substrate
Solution Approach 1:
The acoustic emission sensor detects cracks or deformations before they critically affect device functionality. By performing detection during the fabrication process itself, the system enables early identification of damage, allowing for preventive measures or sorting of affected devices before they cause electrical failures.
Solution Approach 2:
The resonating indenter acts as an intermediary between the force generating unit and the semiconductor substrate. It transmits mechanical forces while its resonance characteristics change in response to cracks or deformations, providing a sensitive detection mechanism that doesn't require direct high-force contact.
2Measurement precision
If conventional detection methods are used to identify cracks, then damaged devices can be found, but the detection process is slow and costly
Solution Approach 1:
The system replaces slow, conventional visual or manual inspection methods with acoustic emission sensing. The acoustic emission sensor detects mechanical waves generated by crack formation in real-time during fabrication, providing rapid and accurate detection without requiring separate inspection steps.
Solution Approach 2:
The detection process occurs continuously during the fabrication operations themselves. The acoustic emission sensor monitors the semiconductor substrate throughout pressure application, wire bonding, or dicing operations, eliminating the need for separate detection stages and maintaining continuous production flow.
3Reliability
If the resonating indenter contacts the semiconductor substrate at a lateral distance from the force generating unit, then acoustic signals from cracks can be detected, but the system complexity increases
Solution Approach 1:
The resonating indenter serves multiple functions: it acts as both a mechanical contact point for force transmission and as a sensor that detects acoustic emissions from cracks. This multi-functionality reduces the need for separate detection components, simplifying the overall system while maintaining reliable crack detection capability.
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 system enables fast and cost-effective detection of cracks in semiconductor substrates, allowing for the identification of damaged devices and preventing further electrical failures.
Implementation Method 1
a detector unit with a resonating indenter and an acoustic emission sensor coupled to the resonating indenter
Implementation Method 2
an acoustic emission sensor coupled to the resonating indenter, and an evaluation unit configured to evaluate acoustic signals detected by the detector unit
Data Source
AI summary
A system and method for the acoustic detection of cracks in a semiconductor substrate is disclosed. In one example, the system includes a force generating unit configured to apply a force onto the semiconductor substrate, a detector unit comprising a resonating indenter and an acoustic emission sensor coupled to the resonating indenter, and an evaluation unit configured to evaluate acoustic signals detected by the detector unit and configured to determine whether a crack has occurred based on the detected signals. The resonating indenter is configured to contact the semiconductor substrate at a lateral distance from the force generating unit, and wherein the force generating unit and the resonating indenter are configured to contact the semiconductor substrate on the same side.