TOKYO/TAIPEI---Samsung Electronics' ambition to roll out its most advanced processor chip early next year is at risk of being delayed as a result of Japan's tighter export controls on semiconductor materials crucial to South Korean industry, sources familiar with the matter told the Nikkei Asian Review. Tokyo Ohka Kogyo (TOK), Shin Etsu Chemical and JSR, three major suppliers of photoresist chemicals to Samsung's latest and most cutting edge chipmaking project, told Nikkei they did not know if their supplies could continue as normal following the introduction of the new controls on July 4.