Copper wire bonding process characterization and simulation

Conference: CIPS 2020 - 11th International Conference on Integrated Power Electronics Systems
03/24/2020 - 03/26/2020 at Berlin, Deutschland

Proceedings: ETG-Fb. 161: CIPS 2020

Pages: 4Language: englishTyp: PDF

Authors:
Mancaleoni, Alberto (ADG Quality & Reliability, STMicroelectronics, Agrate Brianza, Italy)
Sitta, Alessandro (ADG R&D, FE/BE Fusion, STMicroelectronics, Catania, Italy & Dipartimento di Ingegneria Elettrica, Elettronica ed Informatica (DIEEI), Università degli Studi di Catania, Italy)
Colombo, Alexandra (PQR Lab, STMicroelectronics, Cornaredo, Italy)
Villa, Riccardo (BEMT R&D, STMicroelectronics, Agrate Brianza, Italy)
Mirone, Giuseppe (Universitá degli Studi di Catania, Italy)
Renna, Marco; Calabretta, Michele (ADG R&D, FE/BE Fusion, STMicroelectronics, Catania, Italy)

Abstract:
Copper wires are nowadays replacing the traditional Au material in wire bonding interconnections, due to lower cost, better thermal/electrical properties and reliability performances. The increased hardness of Cu imposes higher bonding force and ultrasonic power during the wire-bonding process, increasing the risk of stress-induced bondpad damage. The aim of the presented work has been the modeling and characterization of stress and deformations resulting from the ballbonding phase. A Finite Element Model has been developed and benchmarked with experimental samples obtained by freezing the ball bonding process at different steps, on which the deformations occurred in the bonded copper ball and in the bondpad layers have been measured through Plasma-FIB cross sections.