Evaluation on Tungsten CMP Characteristic using Fixed Abrasive Pad with Alumina

알루미나 고정입자패드를 이용한 텅스텐 CMP 특성 평가

The fixed abrasive pad(FAP) has been introduced in chemical mechanical polishing(CMP) field recently. In comparison with the general CMP which uses the slurry including abrasives, FAP takes advantage of planarity. resulting from decreasing pattern selectivity and defects such as dishing due to the reduction of abrasive concentration especially. This paper introduces the manufacturing technique of $Al_2$O$_3$-FAP using hydrophilic polymers with swelling characteristic in water and explains the self.texturing phenomenon. It also focuses on the chemical effects on tungsten film and the FAP is evaluated on the removal rate as a function of chemicals such as oxidizer, catalyst, and acid. The removal rate is achieved up to 1000A1min as about 70 percents of the general one. In the future. the research has a plan of the advanced FAP and chemicals in tungsten CMP considering micro-scratch, life-time, and within wafer non-uniformity.