Packaging for an interferometric modulator with a curved back plate

A method of making an electronic device, comprising:

• providing an intermediate device comprising a substrate comprising a first surface and a second surface, wherein the second surface is generally flat, the intermediate device further comprising an array of microelectromechanical devices formed on the first surface of the substrate;
• and
• forming a back-plate over the array of the intermediate device, the back-plate having an interior surface and an exterior surface, the interior surface facing the array with a gap therebetween, the exterior surface facing away from the substrate, wherein a portion of at least one of the interior surface or the exterior surface is curved relative to the second surface of the substrate.

A method of making an electronic device, comprising:

• providing an intermediate device comprising a substrate and an array of microelectromechanical devices formed on the substrate;
• and
• forming a back-plate over the array of the intermediate device, the back-plate having an interior surface and an exterior surface, the interior surface facing the array with a gap therebetween, the exterior surface facing away from the substrate, wherein a distance between the interior surface and the substrate varies across the substrate.