Analysis technique for systematic variation over whole shot and wafer at 45 nm process node

We propose a test structure for systematic variation measurement over the whole shot and wafer area at a 45 nm process node. With this structure, we found that the systematic variation had two kinds of site dependence, one is a wafer scale and the other is a shot scale component. Additionally, the Die-to-Die and Within-Die variations for any chip size are calculated. Then, the systematic variation component has the correlation length more than 16 mm. This shows that it is necessary to take into consideration the Within-Die variation according to the Die size.