Ultratech Inc. has sued a former distributor, claiming it stole and is now marketing proprietary optical thin-film deposition technology. The lawsuit, filed in federal court in the Northern District of California, levels charges against Chinese company Ensure NanoTech (Beijing) Inc., its U.S. subsidiary and company president Dongjun Wang. Wang previously was president of Start Science (Beijing) Co. Ltd., a former sales agent in China for Ultratech and Cambridge NanoTech, a Harvard University startup that Ultratech acquired in 2013. The suit alleges that Wang stole trade secrets from Ultratech and now, through Ensure, manufactures and sells atomic-layer deposition equipment that infringes on Ultratech’s U.S. Patent No. 8,202,575. An Ensure representative could not immediately be reached for comment. Atomic-layer deposition is a technique used for creating nanoscale films for integrated optics, microelectromechanical systems (MEMS), implantable biomedical devices and fuel cells. For more information, visit www.ultratech.com and www.ennano.com.