Selective Dielectric Removal for Failure Analysis of Thin Films on Semiconductor Devices

摘要

Root-cause physical failure analysis of thin films in electronic devices is often challenging. The analyses can produce unusual electrical characteristics or material processing challenges. The most challenging obstacle may be the ability to visually observe the thin-film anomaly. A case study is presented describing a method that was used to observe an 8 to 10 nm thin film of tantalum at the device level. Standard failure analysis techniques and tools were used in a non-standard method to provide visual planar evidence of the anomaly observed, which aided in the completion of the root-cause analysis. The purpose of this paper will be to follow the physical failure analysis of an application-specific integrated circuit (ASIC) module. The goal of the analysis was to understand the root cause of failure for a series of shorted pins across several modules. Signature analysis of the data and electrical verification confirmed the fails and revealed that the short was to a particular power supply.