Application of vector scan electron beam lithography to 45nm node extreme ultraviolet lithography reticles

Extreme Ultra Violet Lithography (EUVL) is expected to meet the manufacturing lithography requirements of the 45 nm node and below. The manufacture of 45 nm EUVL reticles will require advancement in both traditional mask production capabilities (resolution, critical dimension control, image placement and defectivity) as well as requirements uniquely related to EUVL reticles (reflective substrate defects, inspection and defect printability, flatness control and post fabrication protection). Photronics is actively pursuing EUVL reticle capability along two paths. First, the NGL Mask Center of Competency (MCoC) has been developing mask technology to support proximity x-ray, electron projection lithography (EPL) and EUVL for several years. The MCoC has applied high resolution lithography and pattern transfer processes developed for 125 nm and below 1X processes to 4X EUVL masks. In addition, the MCoC is collaborating with suppliers on the development of low defect mask blanks and inspection techniques as well as developing low temperature chemically amplified resist processes and low stress materials deposition and processing specifically for EUVL mask fabrication. Key process technology including high resolution vector scan EB lithography and chemically amplified resist processes and has been transferred from the MCoC to manufacturing sites. Secondly, as a natural extension of the optical reticle product line, EUVL reticles will benefit from current and continued mask manufacturing development. Vector scan e-beam lithography with chemically amplified resists (CARs) will be used at both the Photronics MCoC and manufacturing facilities to improve resolution and productivity for sub 100 nm reticle production.