Challenges Grow For CD-SEMs At 5nm And Beyond

CD-SEM, the workhorse metrology tool used by fabs for process control, is facing big challenges at 5nm and below. Traditionally, CD-SEM imaging has relied on a limited number of image frames for averaging, which is necessary both to maintain throughput speeds and to minimize sample damage from the electron beam itself. As dimensions get smaller, these limitations result in higher levels of n... » read more