Contact hole reflow by finite element method

Abstract

Thermal reflow process is one of many used processes for pattern shrinkage and resolution enhancement technology. In this study, we try to describe the shrinkage phenomena of linear static in contact hole patterns by using the finite element method. The resist of thermal flow replaces into a circular saw blade for the linear conduction thermal analysis. By using a commercial tool such as I-DEAS, the characteristic parameters of shrinkage and deformations due to thermal reflow are analyzed and compared with the experimental results. Hence, for the linear static phenomena, those mechanical simulations can be shown a good prediction of different contact hole patterns with various pattern sizes and duty ratios. In the last part, we describe the effect of surface tension. In thermal reflow process, the side-wall angle of resist profile is decreased by surface tension. Its phenomena are shown as similar in the spin coating process by modeling a dimensionless parameter in spin coating.