다바이스 웨이퍼의 평탄화와 종점 전후의 평탄화 특성에 관한 연구

A study on the global planarization characteristics in end point stage for device wafers

Chemical mechanical polishing (CMP) has become widely accepted for the planarization of multi-interconnect structures in semiconductor manufacturing. However, perfect planarization is not so easily ahieved because it depends on the pattern sensitivity, the large number of controllable process parameters, and the absence of a reliable process model, etc. In this paper, we realized the planarization of deposited oxide layers followed by metal (W) polishing as a replacement for tungsten etch-back process for via formation. Atomic force microscope (AFM) is used for the evaluation of pattern topography during CMP. As a result, AFM evaluation is very attractive compared to conventional methods for the measurment of planarity. mOreover, it will contribute to analyze planarization characteristics and establish CMP model.