Considering the outstanding WORM and WRER characteristics, the TOMDs with the X-ASiO-PVPNP layers (PVP = 10 mol.%) were chosen for the data retention test, which is usually performed by repeating the WRER operation over several thousand cycles464748. Prior to the retention test, the TOMDs were encapsulated with the cross-linked poly(dimethylsiloxane) (PDMS) layers (see Fig. 6a and the method section for the detailed process). As shown in Fig. 6b, water drops were well spread over the channel area in the case of the bare devices without any encapsulation, which implies good interactions between Al electrodes and water molecules. However, the devices encapsulated with the cross-linked PDMS layers showed a restricted spreading of water drop. Next, both devices were immersed into water for 24 h in order to examine the performance of encapsulation. As displayed in Fig. 6c, the Al electrodes in the channel area were safe without any defects in the case of the encapsulated devices, whereas the Al electrode parts were seriously damaged for the bare devices (without encapsulation).