Stage devices are disclosed having especial utility in certain types of
microlithography systems. The stage devices impart controlled motion to a
stage or platform without generating fluctuating electromagnetic fields.
The stage devices include stage-actuators that do not rely on
electromagnetics for operation. Multiple stage-actuators achieve motion of
a slider relative to a guide bar. Each stage-actuator includes at least
two actuator-portions that collectively provide an "inchworm" walking
manner of motion of the slider relative to the guide bar. Each
actuator-portion includes a respective pressure-application member. The
pressure-application members are selectively actuated so as to engage a
respective guide bar in a coordinated manner that serves to "push" the
slider along the guide bar. Each actuator-portion includes a respective
first piezoelectric element that urges the respective pressure-application
member against the guide bar and retracts the pressure-application member
from the guide bar, and a respective second piezoelectric element that
moves the respective pressure-application member in the longitudinal
direction of the guide bar.
