Contact/Via Failure Recovery using Nanosecond Green Laser Annealing
- Journal
- IEEE Transactions on Electron Devices
- Vol
- 72
- Page
- 6976 - 6981
- Year
- 2025
Abstract
The rapid reduction of interconnect critical dimension (CD) in logic devices and the increased contact/via height in 3-D memory devices have led to problematic gap-filling processes and the occurrence of void defects, resulting in increased contact/via resistance or complete contact/via failure. However, the low thermal budget of the back-end-of-line (BEOL) stage limits the temperature range available for conventional thermal processes, such as furnace annealing and rapid thermal annealing. This article presents an approach to address contact/via failures, using nanosecond green laser annealing (NGLA) with a low energy fluence (= 0.1 J/cm 2). By exploiting NGLA’s ability to selectively induce high temperatures for ultrashort durations on metal interconnects, we have developed a process that effectively recovers contact/via failures without compromising the performance of both front-end-of-line (FEOL) and BEOL stages.