Method for making a nano-particulate medium

Abstract

In a method for making a nano-particulate medium, platinum, silicon nitride and a nitride of a magnetic element which will disassociate under thermal processing in a vacuum are sputtered onto a substrate in predetermined quantities. The substrate is subjected to a rapid thermal-processing operation in a vacuum, in which the substrate is raised over a given period of time to a temperature at which the nitride of the magnetic element disassociates, releasing nitrogen by diffusion and leaving behind the magnetic element. The substrate is allowed to cool. The magnetic element alloys with the platinum to form particles which are substantially mono-disperse and substantially uniformly distributed in the silicon nitride. The alloying process takes place immediately the nitride of the magnetic element disassociates. The magnetic element is preferably cobalt and the substrate is preferably also raised to a temperature which allows the formation of a PtCo alloy in a tetragonal crystalline form.

Dependencies are inferred from the claim text.