Investigations of the Effects of the Orientation of AlN-Based Complementary Resistive Switches

Due to the development of the Internet of Things (IoT), physically unclonable function (PUF) has also been developed. In this study, aluminum nitride (AlN)-based complementary resistive switches (CRSs) with three different orientations were fabricated. We observed that the resistance values of the (100)-orientation and (002)-orientation AlN-based devices in the high resistance state (HRS) were very messy. This feature is quite appropriate for PUF, because PUF must be unique and unpredictable. In addition, we also verified the prerequisite ( $\vert {V}_{\text {reset}}\vert > \vert {V}_{\text {set}}\vert $ /2) for fabricating CRS using bipolar resistive switches (BRSs) through experiments. This prerequisite can be used to predict the suitability of CRS devices for manufacturing. We believe this work could help in determining the preferable AlN orientation for PUF applications.