An apparatus for fabricating electronic displays comprises a glass substrate that includes pixel arrays formed on the glass substrate. Individual pixels of the pixel arrays include pixel walls to retain a first fluid, such as oil. The pixel arrays may include an edge seal to retain a second fluid, such as an electrolyte solution, that overlays the pixel walls and the first fluid. The glass substrate also includes a hydrophobic strip formed on the glass substrate. A wettability between the first fluid and the hydrophobic strip is different from a wettability between the second fluid and the hydrophobic strip.