1. A nonvolatile memory cell comprising: a pillar comprising a conductive or semiconductor material, the pillar having a pillar sidewall and comprising a vertically oriented diode; a dielectric spacer above the pillar, the dielectric spacer having an outer sidewall and an inner sidewall, wherein 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; a dielectric fill material surrounding the pillar and the dielectric spacer, and a silicide-germanide layer between the pillar and the phase-change material and in direct physical contact with a bottom surface of the phase-change material.