A slim spindle motor and a micro-drive apparatus including the slim
spindle motor are provided. In the spindle motor, a hub is rotatably
mounted on a base plate by ball bearings. The hub is used to seat a disk
thereon. A ring-shaped magnet is engaged to the outer boundary of the
hub. A stator is formed by arranging a plurality of yokes in a round
shape around the outer boundary of the ring-shaped magnet. The yokes
include cores having curved ends to reduce the central axis offset
between the yokes and the ring-shaped magnet. Most of the yokes include
coils that cover the cores. Since the central axes of the yokes in the
stator are made collinear with the central axis of the ring-shaped
magnet, the slim spindle motor can operate stably.