The ​Trump administration will announce as ​soon as Thursday a 15% tariff and a series of price floors on products made from polysilicon, ‌the key ⁠raw ⁠material used in solar panels and semiconductors, according ​to four sources familiar with the matter.The move aims ​to protect U.S. polysilicon factories from growing Chinese ambitions in the chip supply chain.The ​proclamation by U.S. President Donald ⁠Trump is ‌expected to include minimum import ​prices ​on polysilicon, wafers, cells and modules, ⁠or solar panels, and a 15% ​tariff on the polysilicon derivatives, the ​four sources said.The administration's plan to pursue a hybrid system combining a minimum import price with tariffs was first reported by Reuters.Trump's year-long national security investigation into ‌polysilicon by the Commerce Department also has major implications for the growing ​domestic solar ​manufacturing industry ⁠at a time when the U.S. leader has rolled back federal support for renewable energy.The Commerce ​Department and the White House did not immediately respond to requests for comment.