Memory devices and methods of programming and forming the same are disclosed. In one embodiment, a memory device has memory cells contained within dielectric isolation structures to isolate them from at least those memory cells in communication with other bit lines, such as to facilitate forward-bias write operations. The dielectric isolation structures contain an upper well having a first conductivity type and a buried well having a second conductivity type. By forward biasing the junction from the buried well to the upper well, electrons can be injected into charge-storage nodes of memory cells that are contained within the dielectric isolation structures.