Method and system for lithography using phase-change material

Methods and systems are provided for forming an electrical interconnect layer between two layers of an integrated circuit. The interconnect layer is formed using a material having a first electrical conductivity corresponding to a first state and a second electrical conductivity corresponding to a second state, where the first electrical conductivity is different from the second electrical conductivity. An area of the material of the interconnect layer may be selected, for example, using a mask. Then energy may be applied to the selected area to change the electrical conductivity of the material in the selected area of the interconnect layer. Thus, the present invention may be used to implement optical memory devices which may be read by an electrical circuit.