Atomic layer deposition (ALD) is a chemically self-limiting deposition technique that is based on the sequential use of a gaseous chemical process. A thin film (as fine as -0.1 ? per cycle) results from repeating the deposition sequence as many times as needed to reach a certain thickness. The major characteristic of the films is the resulting conformality and the controlled deposition manner. Precursor selection is key in ALD processes, namely finding molecules which will have enough reactivity to produce the desired films yet are stable enough to be handled and safely delivered to the reaction chamber.