Methods of making MEMS devices including interferometric modulators
involve depositing various layers, including stationary layers, movable
layers and sacrificial layers, on a substrate. A non-planar surface is
formed on one or more layers by flowing an etchant through a permeable
layer. In one embodiment the non-planar surface is formed on a
sacrificial layer. A movable layer formed over the non-planar surface of
the sacrificial layer results in a non-planar interface between the
sacrificial and movable layers. Removal of the sacrificial layer results
in a released MEMS device having reduced contact area between the movable
and stationary layers when the MEMS device is actuated. The reduced
contact area results in lower adhesion forces and reduced stiction during
actuation of the MEMS device. These methods may be used to manufacture
released and unreleased interferometric modulators.