The extraordinary development of multimedia technologies and services over the last few years has resulted in a race to increase recording density. The main limit on present magnetic recording techniques appears to be the “paramagnetic limit” i.e. the size beneath which recorded bits fades away by thermal effect.

Numerous phase transition methods are already known whereby a material is caused to pass from one phase to a more ordered phase by applying heat treatment. Numerous methods are also known that enable ordered phases of a material to be obtained directly at high temperature.

Nevertheless, the use of high growth temperature (>350degC) is a major drawback in an industrial application since in addition to being relatively complex and expensive in energy terms, it can give rise of irreversible modifications of the substrate used for the recording medium.

Mr. Chappert’s invention made available a method for chemically ordering a magnetic alloy at low process temperature.