Abstract
The market demands for higher pin counts and more chips functionality pose challenges in conventional wire bonding. However, insulated Cu wire technology enables fine and ultra-fine pitch wire bonding as the insulator coating on the bare wire prevents wires shorting problem. This paper presents the study on the stitch-bonding process optimisation and its challenges for the insulated Cu wire with a diameter of 20 µm. Insulated Cu stitch bond samples show 37% lower stitch pull strength than that of bare Cu. The cross-sectioned insulated Cu stitch bond shows that there is an insulation residue between the Cu stitch and the Au-plated substrate, potentially resulting in lower stitch pull performance. However, after isothermal aging at 225°C for up to 78 hours, the stitch pull results for insulated Cu wire passed the industry reliability standard, without any lifted bond. A detailed comparison study was performed for the insulated Cu and the bare Cu stitch bonding.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.