Electro-Optical Operation of Electrical Probe Phase-Change Memory With Ultra-High Electrically Conductive Capping Layer

An electrical probe phase-change memory using an ultra-high electrically conductive capping layer allows for a successful write of the amorphous bit without thermally damaging the device. Due to the severe current spreading effect, the recorded bit, however, cannot be sensed based on the conventional electrical means. We, therefore, developed a numerical optical model to calculate the device transmission resulting from a focused spot of a mobile scanning near-field optical microscopy. The feasibility of using this novel approach to distinguish bits from their background is also demonstrated.