Tunable UV-flash krypton lamp array useful for large area deposition and in situ UV annealing of Si-based dielectrics

A low pressure VUV flashlamp at 100 Torr has been developed as a tool for 'cold' UV CVD and processing. The current density is related in a tunable fashion to the VUV spectral distribution (160-260 nm) up to 20 Hz. A high brightness (3400 W/Hz cm² sr) Kr flashtube was shown to be a superior VUV source to Xe and Ar for Si-based dielectrics. The VUV efficiency of the Kr flashlamp, operated at up to 10 kA/cm², is relatively high, up to 10%, in the spectral region. By setting four efficient Kr flashtubes, in a separate cavity, a lamp source, together with the UV CVD system characteristics, are shown useful to overall 'cold' processing, with focus on uniform large area, cleaning, and in situ deposition, up to 3% for 3″. The deposition rates are conveniently high, ∼100 Å/min at 350°C, but well controllable to obtain several dielectric thin films on III-V materials: silicon dioxide, nitridised silicon dioxide, and silicon nitride. Device quality electrical and optical features for III-V technology are demonstrated: a zero-hysteresis MIS-InP and as a proof of the passivation of GaAs surface, the MIS-GaAs capacitor.