AXT Inc., a Fremont, Calif.-based manufacturer of compound semiconductor substrates for the fiber optics and communications industries, has appointed John J. Cerilli as vice president of global sales and marketing, effective immediately. Cerilli joins AXT with more than 29 years of semiconductor experience in areas such as marketing research services, new business development, capital equipment sales, customer service, wafer fab operations, technical recruiting and training. Most recently, he was director of sales and marketing for Aixtron-AG, a supplier of MOCVD (metallorganic chemical vapor deposition) equipment, covering the US, Japan, Taiwan, Korea and China.