Abstract: Provided is a memory device including a channel layer, a first dielectric constant change layer on the channel layer, a second dielectric constant change layer spaced apart from the first dielectric constant change layer, and a diffusion barrier layer between the first dielectric constant change layer and the second dielectric constant change layer, wherein the first dielectric constant change layer and the second dielectric constant change layer include oxygen vacancies.

Abstract: Provided is a semiconductor memory device including cylinder type storage nodes and a method of fabricating the semiconductor memory device. The semiconductor memory device includes: a semiconductor substrate including switching devices; a recessed insulating layer including storage contact plugs therein, wherein the storage contact plugs are electrically connected to the switching devices and the recessed insulating layer exposes at least some portions of upper surfaces and side surfaces of the storage contact plugs. The semiconductor device further includes cylinder type storage nodes each having a lower electrode. The lower electrode contacting the at least some portions of the exposed upper surfaces and side surfaces of the storage node contact plugs.