1. A memory cell comprising: a first electrode; a second electrode; semiconductive material intermediate the first and second electrodes, the semiconductive material comprising a plurality of mobile dopants which move from a first region of the semiconductive material to a second region of the semiconductive material as a result of an application of a voltage across the first and second electrodes; wherein a capacitance of the memory cell changes from a first capacitance corresponding to a first programmed state of the memory cell to a second capacitance corresponding to a second programmed state of the memory cell as a result of the movement of the mobile dopants; and wherein the semiconductive material has different dielectric thicknesses when the memory cell is in the first and second programmed states.