The reliability of a via hole filling structure using selective tungsten CVD by a cold-wall reactor using WF6 and SiH4 has been studied. It has been experimentally determined that the reliability for the electromigration of a tungsten-filled via hole structure is significantly improved compared with that for a conventional non-filled via hole structure. Via hole resistance change during the electromigration test was also evaluated. A phenomenon wherein via hole resistance increases due to Si migration was found, specifically under high-temperature conditions. However, it is negligibly small for the usual operating conditions. The results are considered pertinent to the development of VLSI/ULSI devices.
|Number of pages||7|
|State||Published - 1988|