1. A method for forming a memory having a plurality of reversibly programmable memory cells, the method including: forming a plurality of first electrodes made of copper on a substrate; forming a passive layer including copper sulfide on each of the plurality of first electrodes; selectively forming a polymer layer only over the passive layer on each of the plurality of first electrodes to form an active layer thereon by exposing the passive layer to a monomer gas such that material in the monomer gas self-assembles only on the passive layer on each of the plurality of first electrodes to form the polymer in the active layer, the polymer having a reversibly variable electrical conductivity upon the introduction and removal of charged species from the passive layer, and forming a plurality of second electrodes over the active layer.