Seal Ring Test Pad Layout for Precise Wafer-Level HEMT Testing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wafer-level reliability testing for semiconductor devices, such as high-electron-mobility transistors (HEMTs), requires artificial measurements due to limitations in detecting early life failures and defects, necessitating an improvement in testing methodologies.
Innovation Solution
The implementation of a method that includes forming test pads and a seal ring structure during the semiconductor device fabrication process, allowing for electrical testing at the wafer level without the need for additional alignment, and utilizing a metal pattern with specific pad configurations to apply signals and measure parameters, thereby enhancing testing precision and efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If artificial measurements are used for HEMT reliability testing, then testing accuracy can be maintained, but testing efficiency and productivity are reduced
Solution Approach 1:
The patent replaces manual artificial measurements with an automated electrical testing system. Test pads are formed on the semiconductor wafer and connected to a probe card that automatically applies electrical signals and measures parameters, eliminating the need for manual intervention while maintaining measurement accuracy through precise electrical characterization.
Solution Approach 2:
The testing system is designed to perform self-aligned electrical measurements where the test pads are automatically positioned and connected during the wafer-level testing process. The probe card aligns with the test pads without requiring manual adjustment, enabling automated high-throughput testing that maintains precision while significantly improving productivity.
2Productivity
If traditional wafer-level testing methods are used, then testing speed is improved, but measurement precision and defect detection capability are insufficient
Solution Approach 1:
The patent divides the wafer into multiple independently testable regions with dedicated test pads for each semiconductor device. This segmentation allows parallel testing of multiple devices simultaneously while providing precise individual characterization of each device's electrical parameters, thereby improving both throughput and measurement precision.
Solution Approach 2:
The patent introduces test pads as intermediary structures between the semiconductor devices and the probing system. These test pads serve as dedicated measurement points that enable precise electrical characterization without requiring direct access to the device terminals, thereby improving measurement accuracy while maintaining fast wafer-level testing speed.
3Manufacturing precision
If manual alignment procedures are used for testing, then positioning accuracy is achieved, but device complexity and time consumption increase
Solution Approach 1:
The test pads are pre-formed during the semiconductor fabrication process at their final positions, eliminating the need for subsequent alignment procedures. This preliminary positioning ensures precise location accuracy while simplifying the testing process, as the probe card simply needs to locate the pre-defined test pad positions without complex alignment steps.
Data Source
AI summary
The present disclosure provides a semiconductor device. The semiconductor device includes: a substrate including a transistor, wherein the semiconductor device is surrounded by a seal ring; an interconnect structure over the transistor; a recess on a sidewall of the seal ring; a test pad in the interconnect structure, wherein the test pad extends from the interconnect structure to the recess of the seal ring.