  We have developed a process to mass-produce quantum dot micropillar cavities
using direct-write lithography. This technique allows us to achieve high volume
patterning of high aspect ratio pillars with vertical, smooth sidewalls
maintaining a high quality factor for diameters below 2.0 $\mu$m. Encapsulating
the cavities in a thin layer of oxide (Ta$_2$O$_5$) prevents oxidation in the
atmosphere, preserving the optical properties of the cavity over months of
ambient exposure. We confirm that single dots in the cavities can be
deterministically excited to create high purity indistinguishable single
photons with interference visibility $(96.2\pm0.7)\%$.
