Theoretical Study of the Mechanism for the Reaction of Trimethylaluminum with Ozone.

The mechanism for the reaction of trimethylaluminum (TMA, Al(CH)) with ozone (O) was investigated in detail using density functional theory calculations to understand the atomic layer deposition processes that form aluminum oxide surfaces. We examined the reactions of TMA and some possible intermediates with O and revealed plausible paths to form methoxy (-OCH), formate (-OCHO), bicarbonate (-COH), and hydroxyl (-OH) species. These species have been observed in previous experimental studies. It was shown that TMA easily reacts with O to generate the Al(CH)(OCH)(O) intermediate. The subsequent reaction between the OCH and O groups finally generated an intermediate having a formate group. When all of the CH groups are converted into OCH or OCHO, O will react with these groups. In the latter reaction, bicarbonate was shown to be formed.