Development of the miniature hemispherical tilt stage driven by stick-slip motion using piezoelectric actuators

Miniature hemispherical stage has been proposed for improvement of microscopic observation and manipulation. The stage can be rotated in arbitrary direction under a scanning electron microscope. The stage is composed of a hemisphere and three drive units. Besides, the drive unit is composed of a drive ball and two piezoelectric actuators. The drive ball is moved by two piezoelectric actuators, which are orthogonally arranged, in a plane. The movable plane of each drive ball is same as the tangent plane between the hemisphere and each drive ball. The hemisphere on three drive balls is rotated in arbitrary direction by stick-slip motion of each drive ball. The rotational direction of the stage can be controlled by the movable directions of each drive ball. In this paper, the design and fabrication of the small hemispherical stage are described. The rotational directions of the stage are evaluated using a laser autocollimator.