Seoul Semiconductor alleges that Nichia's white, blue, green and UV LEDs all infringe US patent 5,075,742, which is owned by Seoul. The patent was granted in December 1991.
Seoul Semiconductor says that the patent covers technology related to the semiconductor layer used for white, blue, green and UV LEDs and laser diodes. This was already issued in Japan, Germany, France, United Kingdom and United States.
The patent relates to a method to reduce dislocations in a semiconductor layer by the growth of a sequence of three-dimensional inclusions in the layer.
Seoul Semiconductor is seeking an injunction, and damages adequate to compensate for past and future infringement. Seoul Semiconductor says it will also continue to exercise the patent right against companies using Nichia’s products.
Seoul Semiconductor has retained Weil, Gotshal & Manges LLP to prosecute these claims against Nichia. The litigation team is led by David Radulescu, who was a leading counselor representing Cree when Nichia filed a lawsuit against the US LED maker in 2002.