Applied Materials, which has significant business supplying China, is among those believed to ​have received a letter from the U.S. Department of Commerce. | Courtesy Applied Materials / via REUTERS NEW YORK – The U.S. Department of Commerce last week ordered multiple chip equipment companies to halt certain tool shipments to China's second-largest chipmaker, Hua Hong, its latest action to slow the country's development of advanced chips, according to two people familiar with the matter. The department sent letters to at least a handful of companies informing them of the new ​restrictions on tools and other materials destined for two Hua Hong facilities that U.S. officials believe may make China's most sophisticated chips, the people said. Top ‌U.S. chip ‌equipment companies Lam Research, Applied Materials and KLA, each of which has significant business supplying China, were among those believed to ​have received a letter, the sources added.…