February_EDFA_Digital

edfas.org ELECTRONIC DEV ICE FA I LURE ANALYSIS | VOLUME 24 NO . 1 10 indentation on multilayer stacks by a three-parametric Weibull distribution. Additional to the Weibull slope m and shape, which is here the characteristic force F char , a third parameter γ , the so-called location parameter, is introduced. This improveddistribution function considers the physical behavior of thin layers, which have a lower fractural stress limit, where no cracks occur. CONCLUSION This article presented a novel AE testmethod to detect cracks in brittle semiconductor layers during contacting by pointed tip indenters. The process is similar to wafer probing and can be used to characterize the mechanical robustness of multilayer stacks. Additional to the test benchsetup, themeasurement conceptwasdiscussedand the data analysis process explained. Three examples dem- onstrated the capability for crack probability assessments. The accuracy of the AE test method was correlated by conventional failure analysismethods. It was proven that a highly accurate, reliable, and efficient detection of oxide cracks using the AE test method is possible even in the nanometer scale dimension. So in the future, thismethod canbe applied to characterize semiconductor BEOL stacks for probing and other stress-related processes during the manufacturing flow. Furthermore, the results have shown that the two- parametric Weibull distribution function does not accu- rately describe the crack probability for thin, brittle layers. This observation leads to a new hypothesis to improve the model for the crack probability during indentation on multilayer stacks by a three-parametric Weibull distri- bution. Further investigations are continuing at Infineon Technologies AG to prove this hypothesis. REFERENCES 1. M. Unterreitmeier: “Contact Related Failure Detection of Semi- conductor Layer Stacks using an Acoustic Emission Test Method,” FAU Forschungen, Reihe B, Medizin, Naturwissenschaft, Technik Band 33, FAU University Press, Erlangen, Germany, 2020, DOI: 10.25593/978-3-96147-306-9. 2. M. Unterreitmeier, et al.: “An Acoustic Emission Sensor System for Thin Layer Crack Detection,” Microelectronics Reliability, 2018, Vol. 88-90, p. 16-21. ABOUT THE AUTHORS Marianne Unterreitmeier studied renewable energies – electrical engineering (B.Eng.) and micro- & nanotechnology (M.Sc.) at the University of Applied Sciences in Munich. She received her master’s degree in 2016 with two awards: “Oskar-von-Miller Award 2016 for Excellent Academic Achievement” and “University Award 2016 for Best Degree in Micro- & Nanotechnology.” During her studies, she was a part-time working student at ZAE Bayern in Munich. Later, she moved to Infineon Technologies in Munich for her master’s thesis on wafer test. Subsequently, she accepted an offer there for her doctoral research study in the field of acoustic event monitoring in cooperationwith the FAU Erlangen-Nuremberg, OTH Regensburg. Unterreitmeier achieved the Best Paper Award at the ESREF 2018 conference in Aalborg, completed her Ph.D. work in 2019 with honors, and won the Regensburger Award for Women in Science and Art in 2021. She is still enthusiastic for her research topic and happy to continue as a permanent employee at Infineon’s Test Technology and Innovation department. Oliver Nagler finalized his diploma degree (Dipl.-Ing.) of aerospace engineering at the Technical University of Munich in 1994 and receivedhis physical doctorate degree (Dr.-Ing.) in electrical engineer- ing fromtheBundeswehr UniversitätMunich in2008. He startedhis career as a researchengineer at the Fraunhofer Institut for Solid State Technology in Munich in 1995. Since 1999, he’s been an employee at Infineon Technologies AG, Neubiberg, Germany, currently in the department of Test Technology and Innovation. He is a lead principal for wafer test technologies and head of Infineon’s R&D probing lab. Nagler holds several patents and international publications in probing technology and processes including acoustic emission test method. In cooperationwith national and international universities, he is regularly supervising bachelor, master, and Ph.D. students.