Suppression Of Magnetic Trench Material In Bit Patterned Media Fabricated By Blanket Deposition Onto Prepatterned Substrates

摘要

An attractive approach for bit patterned media fabrication is the blanket deposition of magnetic material onto prepatterned substrates with elevated pillars and recessed trench areas. One issue with this method is the residual magnetic material in the trenches that causes disturbing stray fields during writing and readback. Here we present a technique to suppress the magnetic moment in the trenches with an additional annealing step by using prepatterned substrates consisting of SiN pillars on a Si wafer. The annealing triggers an interdiffusion process between the magnetic media and the Si in the trenches that results in the formation of a nonmagnetic silicide, while the magnetic moment on top of the SiN pillars remains substantially unaltered.