A plurality of piezoelectric elements are arrayed two-dimensionally. A plurality of electrodes are respectively formed on the plurality of piezoelectric elements. A plurality of non-conductive members have columnar shape and are arranged on the plurality of electrodes. A plurality of internal metal layers are respectively provided for the plurality of non-conductive members. The internal metal layers reach from arrangement surfaces of the non-conductive members to other surfaces of the non-conductive members. The arrangement surfaces are opposite to the other surfaces.