Combination of Aluminum Tape and Sulfuric–Nitric Acid for uDFN Decapsulation with Copper Metallization Preservation
Combination of Aluminum Tape and Sulfuric–Nitric Acid for uDFN Decapsulation with Copper Metallization Preservation
Thursday, October 8, 2026: 8:40 AM
Summary:
The demand for smaller semiconductor devices has increased the use of ultra-thin dual flat no-lead (uDFN) packages, especially in automotive and industrial applications. These packages, typically around 1000 µm × 1500 µm, present challenges in failure analysis, particularly during decapsulation. Their small size and the presence of copper metal lines make them highly vulnerable to chemical damage, which can affect device functionality and limit further electrical verification. This study introduces a decapsulation technique that uses aluminum tape combined with a sulfuric–nitric acid mixture to protect copper metal lines and prevent damage. The method enables controlled removal of the package mold while safely exposing the active circuit. As a result, device integrity and functionality are maintained throughout the process. Experimental findings show that this approach significantly reduces copper metal line damage and improves overall decapsulation reliability compared to conventional methods. This makes the technique a practical and effective solution for failure analysis of small uDFN devices.
The demand for smaller semiconductor devices has increased the use of ultra-thin dual flat no-lead (uDFN) packages, especially in automotive and industrial applications. These packages, typically around 1000 µm × 1500 µm, present challenges in failure analysis, particularly during decapsulation. Their small size and the presence of copper metal lines make them highly vulnerable to chemical damage, which can affect device functionality and limit further electrical verification. This study introduces a decapsulation technique that uses aluminum tape combined with a sulfuric–nitric acid mixture to protect copper metal lines and prevent damage. The method enables controlled removal of the package mold while safely exposing the active circuit. As a result, device integrity and functionality are maintained throughout the process. Experimental findings show that this approach significantly reduces copper metal line damage and improves overall decapsulation reliability compared to conventional methods. This makes the technique a practical and effective solution for failure analysis of small uDFN devices.