A programmable link structure for use in three dimensional integration (3DI) semiconductor devices includes a via filled at least in part with a phase change material (PCM) and a heating device proximate the PCM. The heating device is configured to switch the conductivity of a transformable portion of the PCM between a lower resistance crystalline state and a higher resistance amorphous state. Thereby, the via defines a programmable link between an input connection located at one end thereof and an output connection located at another end thereof.