TOKYO, Dec 18 -- Rohm Co. Ltd., A manufacturer of semiconductors based in Japan, will form a technical alliance with Cree Inc. in the area of GaN-based blue LEDs and blue-violet semiconductor lasers based on silicon carbide. Cree is a developer and manufacturer of semiconductor materials based in North Carolina. The jointly developed LEDs will be available by mid 2001.Cree and Rohm have also signed a five-year exclusive license agreement granting Cree rights in certain US patent of Rohm relating to LEDs/semiconductor lasers. Rohm will eventually manufacture and market blue semiconductor lasers, used to read high-capacity digital video discs (DVDs).