A spindle motor structure including a spindle motor installed on a base
and having a hydrodynamic bearing supporting a shaft to be capable of
rotating using hydrodynamic pressure and a driving source rotating the
shaft using an electromagnetic force. A circuit board is installed to
face the base and supplies driving power to the driving source. A heater
is installed on the circuit board at a position facing the hydrodynamic
bearing and heats the hydrodynamic bearing.