Method to Control Polymer Generation During Thick Top Metal Process to Reduce Sidewall Defects

This paper presents a novel approach to control sidewall polymer coverage generated during thick top metal etch by implementing a reticle transmission (RT) cut-off at both the masking and the metal etch stages. This is achieved by adjusting the photoresist thickness as well as the etch recipe chemistry. This comprehensive strategy aims to enhance device performance, reduce manufacturing complexities, and improve the overall process yield. Furthermore, the compatibility of this approach with existing manufacturing processes minimizes the need for extensive process modifications or investments into new equipment.