A magnetic recording medium comprising: a non-magnetic substrate; a ferromagnetic metal thin film provided on the non-magnetic substrate; a filmlike first carbon layer provided on the ferromagnetic metal thin film; and a hard and amorphous second carbon layer provided on the first carbon layer; the first...http://www.google.com.tw/patents/US5364690?utm_source=gb-gplus-share專利 US5364690 - Magnetic recording medium comprising a ferromagnetic metal film and two carbon protective layers
