Embodiments of the present disclosure describe a liner for a phase change memory (PCM) array and associated techniques and configurations. In an embodiment, a substrate, an array of phase change memory (PCM) elements disposed on the substrate, wherein individual PCM elements of the array of PCM elements comprise a chalcogenide material and a liner disposed on sidewall surfaces of the individual PCM elements, wherein the liner comprises aluminum (Al), silicon (Si) and oxygen (O). Other embodiments may be described and/or claimed.