Effects of interfacial organic layers on thin film nucleation in atomic layer deposition

Atomic layer deposition (ALD) of titanium nitride (TiN) on silicon dioxide and silicon dioxide modified by self-assembled monolayers (SAMs) with different structures and functional terminations has been investigated employing molecular beam techniques. On the –CH3 terminated SAMs, growth is significantly attenuated over that observed on clean SiO2, more than an order of magnitude for the thicker SAMs, and involves islanded, nonuniform growth. ALD is also observed on SAMs with reactive end groups, –OH and –NH2, but growth is uniform and attenuated only by approximately a factor of 3, independent of the thickness of these SAMs.