A perpendicular magnetic recording medium having a substrate, an amorphous
soft underlayer of thickness 30 nm or greater, and a granular magnetic
recording layer for perpendicular recording is disclosed. The granular
magnetic recording layer includes a non-magnetic region between magnetic
grains, wherein the non-magnetic region includes metal nitride or metal
carbide and provides exchange decoupling between the magnetic grains. The
perpendicular recording medium of this invention reduces DC noise and
increases media signal-to-noise ratio; it reduces surface roughness,
which in turn reduces the head-to-media spacing and the head-to-amorphous
soft underlayer spacing.