AGING OF PHOTOCHEMICAL VAPOR-DEPOSITED SILICON-OXIDE THIN-FILMS

Further development of the microelectronic technology requires the gro wing of stable and passivated dielectric thin films. Photochemical pro cesses are very promising methods to obtain silicon dioxide films for microelectronic purposes. In this article, the aging of silicon oxide films obtained by ArF laser chemical vapor deposition at low temperatu re is studied. The evolution of the properties of films has been follo wed up using infrared spectroscopy and ellipsometry, and compared with aging of thermally oxidized silica films. The role of moisture in fil m aging is also clarified by comparing films exposed to humid and to d ry atmospheres. Si-OH groups are incorporated into the film in a speci fic local bonding environment and relaxation in the film structure tak es place while new Si-O groups can be created. Moreover, the dependenc e of the stability of film properties on the processing parameters is analyzed. (C) 1996 American Vacuum Society.