Fin height and
width can have strong impact on device performance variability. Of the two, fin
height variation is generally more critical [18]. Device’s effective electrical
width is directly related to fin height. Hence, any fin height variation due to
variation of fin forming processes directly transfers to device width
variation. In contrast to planar devices, where active area patterning
variation affects only the narrowest of transistors, all fin-based devices
suffer from the same percentage of device width error [18]. This variability is
primarily related to definition of fin height by STI dielectric recess process
after polishing planarization and can reach several percent of every device
width [18].