A memory structure includes: first and second word lines; a high-k dielectric layer disposed on the first and second word lines; a channel layer disposed on the high-k dielectric layer and comprising a semiconductor material; first and second source electrodes electrically contacting the channel layer; a first drain electrode disposed on the channel layer between the first and second source electrodes; a memory cell electrically connected to the first drain electrode; and a bit line electrically connected to the memory cell.