ARF LASER-INDUCED CVD OF SIO2-FILMS - A SEARCH FOR THE BEST SUITABLE PRECURSORS

The ArF laser induced deposition of SiO2 layers has been examined using a variety of different precursor gases in a parallel and (or) perpendicular irradiation configuration. The films deposited at temperatures lower than 400-degrees-C from the vapor phase of liquid precursors like tetramethylsilane (TMS), hexamethyldisilane, diethylsilane (DES) and tetraethoxysilane (TEOS) together with N2O or O2 as oxidizers always reveal Si-O-C and Si-OH vibrations in the FT-IR absorption spectra. Only for TEOS and T greater-than-or-equal-to 400-degrees-C do these peaks disappear. The best results at the lowest process temperatures are obtained using SiH4 and N2O. Deposition rates are in the range of 80 nm/min at 200 Hz laser repetition frequency and at T greater-than-or-equal-to 200-degrees-C SiO2 films are obtained which exhibit an excellent insulating quality. This allows them to be employed for example in a laser circuit restructuring technology for devices.