Abstract
EndPoint Monitor (EPM) of polishing is one of the key technology of CMP. As semiconductor devices scale down, the requirement to oxide CMP process will become higher. On the other hand, the removal rate of film at CMP process is easily influenced by small deviation of characteristic of the consumable that will directly affect to CMP process. In addition, there is initial thickness difference of film itself, so it will become more difficult to meet the target thickness of film with fixed time polishing. To solve these issues, this paper describes optical EPM that can monitor the change of film thickness by the method of optical interference and detect endpoint of CMP.
