Method for forming gate electrodes of semiconductor device using a separated WN layer

摘要

Disclosed is a method for forming gate electrodes using tungsten formed on a tungsten nitride layer by the chemical vapor deposition(CVD) process rather than the physical vapor deposition(PVD) process. According to the method for forming gate electrodes of the present invention, a silicon layer is formed as a conductive layer for gate electrodes. A tungsten nitride layer is formed on the silicon layer, and then the tungsten nitride layer is thermally treated thereby making a surface of the tungsten nitride layer a first tungsten layer. Next, a second tungsten layer is formed by using the first tungsten layer as a nucleation layer according to the CVD process. According to the present method for forming gate electrodes, tungsten can be deposited by the CVD process rather than by the PVD process. Therefore, those problems such as washing equipment and the particle source which are necessarily accompanied with the PVD process can be prevented, thereby improving productivity and yield.