When the first TMA pulse is applied, the TMA molecules are adsorbed onto the oxygen atoms and take surface reactions with hydroxyl groups. During the surface reactions, the substrate total surface coverage then becomes hO þhOH þhAlðCH3Þ2 þhAlðCH3Þ ¼1; where hAlðCH3Þ2 and hAlðCH3Þ stand for the surface coverage of the residual intermediate products of TMA. If we assume the surface reactions only take place between the chemisorbed TMA and hydroxyls, the overall governingequationof surfacedynamicsdur- ing TMA pulse can be formulated by,