The configuration of one or more barrier layers for encapsulating a device is controlled by setting parameters of atomic layer deposition (ALD). A substrate formed with the device is placed on a susceptor and exposed to multiple cycles of source precursor gas and reactant precursor gas injected by reactors of a deposition device. By adjusting one or more of (i) the relative speed between the susceptor and the reactors, (ii) configuration of the reactors, and (iii) flow rates of the gases injected by the reactors, the configuration of the layers deposited on the device can be controlled. By controlling the configuration of the deposited layers, defects in the deposited layers can be prevented or reduced.