Extreme-ultraviolet microexposure tool at 05 NA for sub-16 nm lithography

Abstract

The resolution limit of present 0.3 NA 13.5 nm wavelength microexposure tools is compared to next-generation lithography research requirements. Findings suggest that a successor design is needed for patterning starting at the 16 nm semiconductor process technology node. A two-mirror 0.5 NA optical design is presented, and performance expectations are established from detailed optical and lithographic simulation. We report on the results from a SEMATECH program to fabricate a projection optic with an ultimate resolution limit of approximately 11 nm.

The SEMATECH Berkeley MET pushing EUV development beyond 22nm half pitch

“…To this end, SEMATECH has initiated a plan to implement a 0.5 NA microfield tool at the Advanced Light Source synchrotron facility. A diagram of proposed two mirror optical system [14] is shown in Fig. Il.…”

The SEMATECH Berkeley microfield exposure tool: learning at the 22-nm node and beyond

“…To this end SEMA TECH has initiated a plan to implement a O.S NA microfield exposure tool at the Advanced Light Source synchrotron facility. A diagram of proposed two mirror optical system [17] is shown in Fig. 13.…”

Projection optics for extreme ultraviolet lithography (EUVL) micro-field exposure tools (METs) with a numerical aperture of 0.5

“…The POB's magnification (5X), track length, and mechanical interfaces match the currently installed 0.3 NA POBs [2] [3] [6], so that significant changes to the current tool platforms and other adjacent modules will not be necessary. The distance between the reticle stage and the secondary mirror had to be significantly increased to make space available for the upgraded 0.5 NA illumination modules [1].…”

“…However, a higher NA next generation EUV MET is needed to support materials development for 11 nm half-pitch and smaller features sizes. SEMATECH completed the design of such a 0.5 NA MET in 2007 [1] and started the build of the system in late 2011 with the goal to have two such systems available for supporting materials research in early 2014. The optical design of its projection optics modules is based on a modified Schwarzschild design.…”

“…To upgrade the 0.3 NA METs, a 0.5 NA system (MET5) was designed and proposed with an 11 nm target resolution goal [1]. The primary purpose of these small field (20 µm × 300 µm) tools is to provide very early learning into the extendibility of EUV lithography and in particular in the areas of resists and mask architecture and to help drive materials / technology learning in both areas for patterning at 11 nm half-pitch and below.…”