If a respiratory droplet from a person infected with COVID-19 lands on a surface, it becomes a possible source of disease spread, because while 99.9 percent of the droplet’s liquid content evaporates within minutes, a residual thin film that allows the virus to survive can be left behind. In a new study, researchers explore how the evaporation rate of residual thin films can be accelerated by tuning surfaces’ wettability and creating geometric microtextures on them.