Selective Atomic Layer Deposition with Electron-Beam Patterned Self-Assembled Monolayers

The authors selectively deposited nanolines of titanium oxide (TiO(2)) through atomic layer deposition (ALD) using an octadecyltrichlorosilane (OTS) self-assembled monolayer (SAM) as a nucleation inhibition layer. Electron-beam (e-beam) patterning is used to prepare nanoline patterns in the OTS SAM on SiO(2)/Si substrates suitable for selective ALD. The authors have investigated the effect of an e-beam dose on the pattern width of the selectively deposited TiO(2) lines. A high dose (e. g., 20 nC/cm) causes broadening of the linewidth possibly due to scattering, while a low dose (e. g., 5 nC/cm) results in a low TiO(2) deposition rate because of incomplete exposure of the OTS SAMs. The authors have confirmed that sub-30 nm isolated TiO(2) lines can be achieved by selective ALD combined with OTS patterned by EBL at an accelerating voltage of 2 kV and line dose of 10 nC/cm. This research offers a new approach for patterned gate dielectric layer fabrication, as well as potential applications for nanosensors and solar cells.