A micro-electro-mechanical (MEMS) switch (10, 110) has an electrode (22,
122) covered by a dielectric layer (23, 123), and has a flexible
conductive membrane (31, 131) which moves between positions spaced from
and engaging the dielectric layer. At least one of the membrane and
dielectric layer has a textured surface (138) that engages the other
thereof in the actuated position. The textured surface reduces the area of
physical contact through which electric charge from the membrane can
tunnel into and become trapped within the dielectric layer. This reduces
the amount of trapped charge that could act to latch the membrane in its
actuated position, which in turn effects a significant increase in the
operational lifetime of the switch.
