| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of filling semiconductor features for mutual connection without using complicated apparatuses. SOLUTION: Without using a copper reflow process, semiconductor features 301 such as trenches 302, vias, etc., are filled with copper without trapping voids. An unfilled part of a feature structure before a reflow process becomes a capillary 314 in the feature 301. The volume of the capillary 314 is between about 20% and 90% of the original volume of the feature which should be completely filled with copper. The aspect ratio of the capillary 314 is preferably at least 1.5. The size of the maximum opening of the capillary 314 is less than about 0.8μm. The appropriate temperature of copper in a reflow process should be somewhere in the range of between about 300 deg.C and 600 deg.C or can be increased or decreased between this temperature range. When the aspect ratio of the feature 301 is at least 1.5, copper which is the filling material can be easily drawn into the feature 301 having the capillary 314, by controlling the ratio of the unfilled volume to that of the feature to make the best use of the surface tension and the capillary phenomenon, and no voids are formed along the wall of the feature 301. |
