CoB/Pd multilayers have been fabricated on ultrathin (2 nm) indium tin oxide seed layers with NiFe soft underlayer for perpendicular magnetic recording. In situ heating to 230°C was applied to increase the mobility of the boron atoms so that they can presumably migrate to the grain boundaries to promote grain segregation and inhibit grain growth. It gave a coercivity of 5 kOe and a D50 about 330 kfci for differentiated output signals. Magnetic force microscopy analysis shows that the magnetic domain size has been decreased due to the addition of B in Co layer, which may lead to better recording performances. An areal density of 11 Gb/in2 was achieved at a bit-error-rate of 10-6. As the recording was limited by the wide track width of the head, high flying height, and noisy soft underlayer, it is expected that the media has the potential of more than 30 Gb/in2 in areal density.