1. A nonvolatile memory cell comprising: a pillar comprising a conductive or semiconductor material, the pillar having a pillar sidewall; a dielectric spacer above the pillar, the dielectric spacer having an outer sidewall and an inner sidewall, wherein the outer sidewall is aligned with the pillar sidewall and the inner sidewall defines a reduced recess volume; a phase-change material, wherein some portion of the phase-change material is within the reduced recess volume; and a dielectric fill material surrounding the pillar and the dielectric spacer, wherein the dielectric spacer is formed of a second dielectric material which is different from the dielectric fill material.