Area-Selective ALD of Titanium Dioxide Using Lithographically Defined Poly(methyl methacrylate) Films

Abstract

An approach to area-selective atomic layer deposition techniques based on the use of a lithographically definable polymeric masking layer has been reported. Successful direct patterned deposition of TiO2TiO2 is demonstrated using a poly(methyl methacrylate) masking layer that has been patterned using deep-UV lithography. A number of factors which must be considered in designing patternable polymeric masking materials and processes have been determined and are briefly discussed, including reactivity of the polymer with the atomic layer deposited (ALD) precursor species, diffusion of ALD precursors through the polymer mask, and remnant precursor content in the masking film during ALD cycling.