Analysis of Heat Transfer Process of Plug Formation for VLSI by Laser Radiation

点击翻译按钮获取中文摘要

In order to get basic Knowledge for improving reliability of plug formation for VLSI by a Laser radiation, the two processes that a metal was melted by the laser radiation, and the molten metal flowed and solidified, were investigated analytically and experimentally. The following results were obtained.As a model of the first process, ice (semitransparent material for radiation energy) in an open-top rectangular dimple in a substrate was melted by radiation of a heat source from above, where the size of the dimple was large enough to neglect the effect of surface tension. The analysis and the experiment for the model were made. From the comparison of analytical results with experimental results, the effectiveness of the present analysis was shown. Besides, the influences of blackbody temperature of heat source, the material of the substrate, air bubbles in ice and thermal condition of the substrate on the first process were clarified.As a model of the second process, a pure metal with a microscopic hole was melted by laser radiation from above and the molten metal flowed into the hole and then solidified, where the size of the hole was so small that the surface tension of the molten metal had to be considered. The analysis and experiment for the model were made. From the comparison of analytical results with experimental results, it was clarified that the present analysis could qualitatively simulate the second process. Besides, the results of the analysis performed for the practical hole size and time scale, showed transient behavior of metal from melting to solidification. It was clarified that surface tension mainly governed the phenomenon that molten metal flowed into the microscopic hole.