A hard disk drive including a flexible printed circuit (FPC) in which a
base layer and a cover layer are arranged with a circuit layer
therebetween. In addition, a damping material is coupled at a
predetermined portion of the signal patterns in the circuit layer so as
to cross the signal patterns. The hard disk drive reduces vibration
energy over an entire frequency band to minimize the effect of vibration
on servo control and improve the performance of the hard disk drive.