Impact of bandwidth on contrast sensitive structures for low k1 lithography

Double-patterning ArF immersion lithography continues to advance the patterning resolution and overlay requirements and has enabled the continuation of semiconductor bit-scaling. Over the years Lithography Engineers continue to focus on CD control, overlay and process capability to meet current node requirements for yield and device performance. Reducing or eliminating variability in any process will have significant impact, but the sources of variability in any lithography process are many. The goal from the light source manufacturer is to further enable capability and reduce variation through a number of parameters. Recent improvements in bandwidth control have been realized in the XLR platform with Cymer's DynaPulse^TM control technology. This reduction in bandwidth variation could translate in the further reduction of CD variation in device structures. The Authors will discuss the impact that these improvements in bandwidth control have on advanced lithography applications. This can translate to improved CD control and higher wafer yields. A simulation study investigates the impact of bandwidth on contrast sensitive device layers such as contacts and 1x metal layers. Furthermore, the Authors will discuss the impact on process window through pitch and the overlapping process window through pitch that has been investigated. These improvements will be further quantified by the analysis of statistical bandwidth variation and the impact on CD.