Embodiments of the present invention relate to approaches to effectively let noise on a head slider bonded to a silicon substrate of a microactuator, escape to the ground. A head gimbal assembly (HGA) according to an embodiment of the present invention comprises a microactuator bonded to a gimbal tongue. The microactuator comprises a piezoelectric element and a movable part for moving in response to expansion or contraction of the piezoelectric element. The motion of the movable part causes a head slider to slightly move. The microactuator further comprises a conductive path including an impurity-containing silicon layer formed on the silicon substrate. The conductive path transmits electric charge of the head slider to a suspension. The conductivity of the impurity-containing silicon layer is lower than the one of the silicon substrate so that the noise charge of the head slider may escape to the suspension.