초록 |
In the semiconductor process, chemical mechanical polishing(CMP) has been generally recognized as the promising method to achieve gloval planization for ultralarge-scale intergrated(ULSI) multilevel interconnection. CMP is divided into two groups: oxide CMP and metal CMP. Oxide CMP has been utilized earilier than metal CMP in the semiconductor industry. And, metal CMP is getting on a wide range of use, begining from W CMP until Al CMP and Cu CMP, but more reasearches are required on mechanisms and chemical effects during polishing. There are three main factors to be considered in regard to CMP: removal rates, selectivity and nonuniformity. In metal CMP, aluminium is a relatively soft metal compared to tungsten and copper. Therefore, Al CMP needs more techniques than other metal CMP and confronts a little complicated problems such as suface scratches and dishing defects. Thus, the formation of oxides plays an important role in Al CMP, especially for the purpose of resolving the problems mentioned above. The effects of passivating solutions on the formation of oxide film are investigated.
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