= Solution
\b[Normal <evaporative deposition> gives approximately horizontal films on the resist tops and exposed substrate, with little coating of vertical walls.] A small distant electron-beam-heated source in high <vacuum> gives nearly line-of-sight arrival. Near-normal rays reach the opening floor, while vertical walls present almost no projected area.
The floor film and top film can remain disconnected, which helps a later <lift-off process>. A finite source size, tilted incidence, scattering or sample rotation changes that idealization and may coat one wall or shadow part of the floor. The stated $200\,\mathrm{nm}$ thickness is well below the $1\,\mathrm{\mu m}$ resist height, but this alone does not guarantee a clean break at every real edge.
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