폴리비닐피로리돈 농도에 따른 고 선택비 텅스텐 화학적 기계적 연마연구

Abstract

Abstract

Study of Polyvinylpyrrolidone Concentration on High Selective Chemical Mechanical Planarization of Tungsten

Jeong Gi-Ppeum Dept. of Electronics & computer engineering Graduate School Hanyang University Advised by Prof. Jea-Gun, PARK

Recently semiconductor devices tend to become miniaturized and required higher speed and integration. Therefore increasing number of wiring layers and micro-fabrication technology are required. For this purpose it is necessary to Chemical Mechanical Planarization (CMP) process. CMP process which flatten the surface by chemical action and mechanical force an essential step to ensure the Depth of Focus for the plurality of wiring layers and patterned. CMP mechanism is dependent on the composition and characteristics of the slurry, from these reasons, there is a problem that dishing and erosion. To solve this problem, the slurry having a high selectivity required. This study investigated the effect of polyvinylpyrrolidone (PVP) in the slurry on high selectivity of Tungsten (W) to Silicon Oxide (SiO2) films. To ensure that dishing and erosion will not occur in tungsten CMP, the selection ratio between the tungsten and the silicon oxide film is large. Therefore performed the polishing evaluation by adding Polyvinylpyrrolidone to the slurry. The selection ratio was increased after the addition of the Polyvinylpyrrolidone which was decided by the polishing rate measurement with 4-point probe and Ellipsometer. In addition, dishing and erosion were investigated by the SEM.