Forced flow atomic layer deposition of TiO2 on vertically aligned Si wafer and polysulfone fiber: Design and efficacy of conduit plates and soak function.

The effectiveness of three different designs of conduit plates was verified for even distribution of precursors in a voluminous forced-flow atomic layer deposition (ALD) chamber designed to hold macroscopic elongated substrates vertically. Furthermore, a new "soak function" was introduced in the controlling software of the ALD instrument. This function enabled increase in residence time of the precursor in the chamber without escalating the dosage. The flow of precursors guided by the conduit plates with and without application of the soak function was simulated using computational fluid dynamics. A conformal coating of TiO2 with good uniformity on Si and porous polysulfone fibers was achieved to evidence the design and efficacy of conduit plates and soak function.