STRUCTURAL INTERPRETATION OF THE LOW-TEMPERATURE REFLOW OF BOROPHOSPHOSILICATE GLASSES DOPED WITH BF2 BY ION-IMPLANTATION

The relationship between the composition and the low temperature reflow, low stress, and water durability of BF2 doped borophosphosilicate glasses used as VLSI interlayer insulation or passivation was investigated. These glasses exhibited a slightly lower flow point, lower stress, and higher water durability than the phosphosilicate glasses normally used. Furthermore, borophosphosilicate glasses doped with the BF2 radical by ion implantation showed a somewhat lower stress and a lower flow (730 to 750°C) than undoped borophosphosilicate related to glass structure and their peculiar properties were elucidated by the use of a 'released structure model' derived from an analysis of nuclear magnetic resonance spectra.