Some of TCK’s patents related to silicon carbide (SiC) rings have been invalidated by courts in South Korea.
The company had been in a legal battle with rival DS Techno over patents related to the rings, which are a key material used in the production of 3D NAND.
The Patent Court of Korea on Thursday, in its ruling, validated patents of DS Techno related to material and properties while patents related to manufacturing of TCK were validated.
A day earlier, the Intellectual Property Trial and Appeal Board had also validated TCK’s patents related to manufacturing.
However, the company’s patents related to material and properties were invalidated in both rulings.
TCK had filed a patent infringement lawsuit against DS Techno for the first time in November 2019, claiming the latter infringed its patents on SiC rings.
The rings are used to put the wafers in place; those made with SiC are more durable than those made with quartz or silicon and are used in etching chambers.
TCK had so far dominated the SiC ring market in South Korea thanks mostly to its related patents.
Including those filed against DS Techno, it had filed three lawsuits since 2019 to protect this dominant position.
Following the ruling of the Patent Court of Korea, TCK claimed that it won a total victory and that it will continue to look into whether rivals violated its patents related to manufacturing.
On the other hand, DS Techno said TCK’s patents related to material and properties were invalidated, which means as it has various solutions in manufacture it can work around TCK’s related patents on the matter going forward.