Magnetron sputtering has been used extensively to deposit interconnect layer, diffusion barrier layer, adhesion layer and anti-reflection layer in semiconductor production. As the dimension of VLSI devices get smaller, it is becoming increasingly difficult to deposit these metal layers into high aspect ratio contacts and vias using conventional sputtering method. Coherent sputtering, where a perforated plate (collimator) is placed between the sputtering target and wafer, improves bottom coverage and step coverage. In the recent years, coherent sputtering has been used to deposit titanium, titanium nitride and aluminum films. However, the existence of collimator changes the deposition processes and properties of the deposited films. In this article, we will discuss some of the properties of coherent deposition.