Evaluation of Copper and Gold Wire Bonds in PEM Devices
The shift from gold to copper wire bonds used in plastic encapsulated microcircuits (PEMs) has been gradual for the last few years. Many agencies and critics question the long-term robustness and reliability of copper wire bonds; however, PEM manufacturers have been thoroughly evaluating and optimizing the copper wire bond process over the last few years to produce highly reliable products. When the manufacturing process is optimized and closely controlled and monitored, copper wire bonds can be a reliable and stronger alternate to gold wire bonds. This paper details a copper wire bond study that specifically compares copper wire against gold wire bonds following combined environmental life stress test conditions. In this study, bond pull testing indicates good performance of both copper and gold wire bonds. The methods used in this analysis (destructive physical analysis, wire pull testing, and environmental testing) were effective techniques for evaluation of bond wire integrity, detection of manufacturing defects, and overall assessment of copper and gold wire bond processes. Based on wire bond testing in this analysis, the reliability and integrity of optimally developed copper wire bonds appear to be superior to or even stronger than gold wires in the same package type. Equivalent reliability was demonstrated for both copper and gold wire bonds in this test.Abstract
Contributor Notes
ABOUT THE AUTHORS
Brian Myer is a senior principal electrical engineer in the materials and process engineering department at Raytheon Missiles and Defense, Tucson, Arizona, where he specializes in component testing and failure analysis. He received his bachelor of science in electrical engineering from Boise State University and has spent more than 20 years in the semiconductor industry with both Micron Technology and Texas Instruments. Brian has 10 additional years' experience in the aerospace and defense industry, working advanced failure analysis of microelectronics and integrated circuits at the subsystem level, and has become the Raytheon expert for device analysis and testing of counterfeit devices and counterfeit risk mitigation.
Contact Author: Brian Myer , brian.myer@rtx.com . Materials and Process Engineering, Raytheon Technologies, Tucson, Arizona.
Eric Gallardo is a senior engineer for the materials and process engineering department at Raytheon Missiles and Defense, Tucson, Arizona. He specializes in failure analysis of electrical subsystems and components and has been in the aerospace and defense industry for seven years. He earned his bachelor and master of science degrees in material sciences and engineering from the University of Arizona.
Contact Author: Eric Gallardo , eric.gallardo@rtx.com . Materials and Process Engineering, Raytheon Technologies, Tucson, Arizona.
Dustin Aldridge is a senior principal systems engineer in reliability engineering with Raytheon Missiles and Defense, Tucson, Arizona. He is a specialist in reliability risk analysis. He spent more than 25 years in the automotive industry. He is the recipient of the 2011 IEST Reliability Test and Evaluation Award, an IEST fellow, the director for the product reliability division, an editorial advisor for the Journal of the IEST, and represents IEST on the RAMS board of directors.
Contact Author: Dustin Aldridge , dustin.s.aldridge@rtx.com . Reliability Engineering, Raytheon Technologies, Tucson, Arizona.
Stephen Melosky is an engineering fellow in the materials and process engineering department with Raytheon Missiles and Defense, Tucson, Arizona. He is a specialist in electronic materials, coatings, semiconductors, and component packaging. He spent more than 36 years between both the defense-aerospace and computer-semiconductor industries. He earned his master of science degree from Auburn University in material sciences and engineering.
Contact Author: Stephen Melosky , stephen_melosky@rtx.com . Materials and Process Engineering, Raytheon Technologies, Tucson, Arizona.