Study on 40 Gbit/inch/sup 2/ density molding using heat insulated mold

Optical disk substrates are usually formed using injection-molding method. High mold temperature is necessary to replicate high-density pits, but may cause bad tilt characteristics of substrates. There was a report of a heat insulated mold in which a heat insulating layer was located at the back of a stamper to improve replication characteristics. In this paper we show the results of examination of 40 Gbit/inch/sup 2/ density molding using the insulated mold and the low mold opening speed technology.